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  1. 1. 1 Neurobehavioral Performances Among Lead Exposed Workers In Malaysia: An Early Detection Of Lead Toxicity Mazrura Sahania,1 and Noor Hassim Ismailb a Institute for Medical Research, Kuala Lumpur b Department of Community Health, Faculty of Medicine, University Kebangsaan Malaysia.Abstract The objectives of this study is to evaluate subjective symptoms and neurobehavioral performances amongworkers exposed to lead and its relation with blood lead levels. The methodology of this study was restricted to141 Malaysian battery manufacturing factories male workers with mean (SD) age of 35.2 (9.6) years, years ofemployment 9.1 (7.1), current blood lead concentration 40.5 (16.8) µg/dl were given WHO neurobehavioral coretest battery. Results showed that highly exposed group blood lead level (high ≥ 40 µg/dl) performed less well in4 of 13 responses reported higher subjective symptoms of weakness of lower limbs and anorexia. Significantcorrelation was found between blood lead and Digit Symbol, Digit Forward, Digit Backward, Aiming PursuitTest and Trail B. Regression analysis showed reduction in cognitive, memory and concentration functions at ≤30 µg/dl blood lead levels with maximum lead effect at Digit symbol’s score at 40 µg/dl. In conclusion, thisstudy is consistent with the larger body of neurobehavioral tests in lead exposure and has proven the ability ofthese tests in detecting low level of lead toxicity.Keywords: Blood lead, low level, neurobehavioral test, workers, Malaysia.Introduction toxicity, whereas subclinical evidence of lead poisoning has been reported in The ever increasing interest of neurophysiological and neurobehavioralneurobehavioral test is probably due to its studies (Landrigan 1989; Campara et al.sensitivity shown by psychological 1984; Arnvig et al. 1980). Most of themeasurement techniques to unveil changes neurobehavioral studies undertaken havewhich otherwise would not detected in come from the industrialised countrieshuman. The evidence that this changes are (Seppalainen et al. 1975; Hanninen et al.among the earliest indicators of the 1979; Baker et al. 1984), only few have beenoccurrence of health effects has by now, reported in developing countriesbecome unequivocal. As a consequence this (Jeyaratnam et al. 1985; Maizlish et al.test has come to be regarded as a major 1995; Mohamed 1986).device of major importance for monitoringof potential health hazards (Iregen & The purpose of the present study was toGamberle 1990). assess the neurobehavioral performances among workers exposed to inorganic lead in Clinical manifestation of lead poisoning battery manufacturing factories in Malaysia.such as anaemia, wrist drop, and renalfailure lie at the upper end of the range of1 Correspondence author: Dr. Mazrura Sahani, email:
  2. 2. 2Materials and methods Surrey, United Kingdom. This blood lead measurement was assumed to reflect averageStudy Design and Population Studied exposure. The study design was cross-sectional Neurobehavioral Core Test Batteryand subjects were drawn from two batterymanufacturing factories in the state of To correct the lack of standardisation inSelangor, Malaysia. On average 360 neurobehavioral assessment, the Worldemployees were employed, with local citizen Health Organisation (WHO) Neuro-to foreign workers from Bangladesh ratio behavioral Core Test Battery (NCTB) has1:1. Because of high turn-over of the foreign been advocated as a validated, standardisedworkers and the foreseen difficulties psychological test battery that has been(language problems) in conducting the reported as transcultural (WHO 1986). Thisneurobehavioral test, they were excluded study used 5 tests of NCTB and 1 test fromfrom the study. Eligibility to our study was California University (Trail Making Test).restricted to 141 male workers from 3 major This neurobehavioral is a simple pencil andethnic groups; Malays, Chinese and Indian paper test and test conducted by trainedwho have given consent. Walk-through examiners. All test has been translated fromsurveys were conducted together with an English to Bahasa Malaysia which is theindustrial hygienist to exclude other national language which also has been pre-neurotoxicants in the factories. tested. But the tests were conducted in either Bahasa Malaysia, Chinese or EnglishProcedure according to participants choice. The participants were given Table 1 summarises neurobehavioral testsquestionnaire which covers personal data, used in this study and their domain functionsmedical and occupational history, hobbies,smoking, alcohol consumption and Digit Symbolsubjective symptoms complaints. They were The subject is presented with a key at the topinterviewed and examined physically by one of the page with the numbers 1 to 9of the researchers. Trained examiners blind displayed with their respective matchingto participants’ exposure history conducted symbols. Below are blanks with digitstest in quiet rooms during the beginning of above. The subject must copy thethe shift to avoid effect of fatigue. The appropriate matching symbols for each digitprocedure took nearly one hour per person. based on the key at the top of the page. The number of correct symbols in the 9 secondsBlood Lead Measurement test period is the score. All participants were requested to Digit Spanprovide 10 mls samples of venous blood by Digit span, from Weschler adult intelligencevenepuncture from a forearm for blood lead scale measures short term memory andanalysis by atomic absorption spectrometry attention. In the digit forward the testerin Institute for Medical Research recites group of 3, 4, 5, 6, progressively up(Fairulnizal 1996). Quality control of the to 8 numbers and the subject is requested tomeasurement had been taken care by using repeat each exactly as he hears them. Thecommercial controls from Bio-Rad, USA digit backwards sequence runs from two toand by participating in ‘Trace Elements eight digits and the subject is requested toExternal Quality Assessment Scheme’ repeat them in exactly reversed order. Theorganised by Robens Institute, University of
  3. 3. 3score is the total number of correct sequence drawing. The number correct in 10 trials isindividually. the score.Santa Ana Manual Dexterity Test Trail Making TestThe subject must rotate pegs through 1800. This test has two parts, each consisting of 25The pegs are arranged in 4 rows of 12 pegs circles distributed over a sheet of paper. Inon rectangular board. The number of pegs Trail A the circles contain numbers 1 to 25.rotated in 30 seconds is the score. The test The subject is required to draw a linewas repeated for the preferred, non-preferred connecting the circles in numerical sequenceand both hands. as quickly as possible. Trail B differs from Trail A in that the circles contain numbers 1Table 1. Neurobehavioral tests and the to 13 and letters A to L. In connecting thefunctional domain tested circles the subjects is required to alternate Test Function Domain between the numbers and letters as he proceeds in ascending sequence. The test isDigit Symbol Motor Speed, Visual scored as the number of seconds needed to Scanning, Working finish each part. MemoryDigit Span Short term memory and Questionnaire for Subjective Symptoms attention This questionnaire was adapted fromSanta Ana Motor Speed, co- WHO for assessing subjective symptoms. It Dexterity ordination consist of 20 items grouped systematicallyBenton Visual Visual Perception, into the following subscales; central nervous Retention Memory system, peripheral nervous system, gastrointestinal system and other symptoms.Pursuit Aiming Fine motor control and motor steadiness Statistical MethodsTrail Making Attention, Visual Scanning, Processing All data were entered in dBase IV and Speed analysis was done with SAS. To test the relation of blood lead with its influencingPursuit Aiming Test factors, t-test or chi-square were used. ToWith a pencil, the subject is instructed to dot control the effect of confounding variablesthe centre of circles as quickly and (age, education level, alcohol, tobaccoaccurately as possible. The circle is 2 mm in smoking, exposure to other chemical, usagediameter are arrayed on a paper sheet in 30 of personal protective equipment andcolumns by 40 rows. Excluding outliers, the hobbies) general linear model analysis wasnumber of dotted circles in two 30 s trials is used. Correlation analysis is used to see thethe score. significant of the relations between blood lead, haemoglobin levels andBenton Visual Retention Test neurobehavioral performances. To test theThe subject is shown a drawing for 10 hypothesis of the sensitivity ofseconds composed of geometric figures. neurobehavioral test in comparison withAfter the drawing is removed, the subject is clinical findings and anaemia, t-test, chi-shown four similar looking drawings, only square and multiple regression analysis wereone of which is a true replica of the original. used that incorporate age, education levelThe subject must identify the correct and years of employment.
  4. 4. 4Results Significant difference in score was found between the highly exposed group with the Table 2 shows the summary of the low exposed group (Table 4) in Digitdemographic characteristic of the symbol, Digit forward, Santa Ana Preferredparticipants. The response rate from factory hand, Santa Ana both hands, Benton,A was 78.8% and 81.9% from factory B. Pursuit Aiming and Trail B tests.Blood lead analysis was not performed for 3workers (**) because of the unsuitability ofthe specimens.Table 2. Demographic characteristic of theparticipants Demographic N Mean Range Characteristics (SD)Age (years) 141 35.2 20-69 (9.6)Years employed 141 9.01 0.33-32 (7.1)Education 141 9.0 2-16 (*)Blood lead 138** 40.5 4.9-76.5(µg/dl ) (16.8)Duration of 84*** 11.2 1-30smoking (years) (6.7)*= not available, ***= smokers onlyThe ethnicity of the participants is shown inTable 3 . Participants came from differentjob categories with the majority of themfrom production, maintenance and qualitycontrol sections (71.6%) whereas the otherscame from the technical and packagingsections (10.6%), raw material (4.9%),administrative and marketing (6.3 %) andproduction supervisors (6.4%).Table 3. Ethnic distribution of the participants Ethnic group Numbers Percentages Malay 71 50.4 Chinese 35 24.8 Indian 35 24.8 Total 141 100Neurobehavioral Test Performances The participants were divided into 2groups of highly exposed group with bloodlead levels (PbB) ≥ 40 µg/dl and lowexposed group of PbB < 40 µg/dl accordingto WHO’s biological exposure index.
  5. 5. 5Table 4 . Mean score of neurobehavioral test analysis which revealed the similar resultswith blood lead level (Table 5). PbB < 40 PbB ≥ 40 µg/ dl µg/ dl p- Table 5. Correlation coefficients between Tests Mean Mean value blood lead and neurobehavioral Score Score performancesDigit Symbol* 49.6 37.4 0.02 Tests N Correlation p- coefficients valueDigit Forward 9.4 8.5 0.19 Digit Symbol* 135 -0.4348 0.00Digit 7.3 5.4 0.01 Digit Forward* 135 -0.2107 0.02Backward* Digit Backward* 134 -0.3040 0.00Santa Ana 25.1 23.5 0.04Preferred Santa Ana 135 -0.0469 0.14Hand* Preferred HandSanta Ana 22.6 22.4 0.05 Santa Ana Non- 134 -0.0529 0.91Non-preferred Preferred Handhand Santa Ana Both 132 -0.0141 0.17 HandsSanta Ana 30 26.5 0.02Both Hands* Benton 135 -0.1520 0.18Benton* 8.7 7.8 0.02 ‘Aiming’ * 135 -0.2476 0.00‘Aiming’ * 213 182 0.00 Trail A 133 0.1221 0.16 Trail B* 132 0.3040 0.00Trail A 45.3 55.5 0.05 seconds seconds (Correlation analysis,* = p < 0.05)Trail B* 88 121 0.00 Prevalence of Subjective Symptoms seconds seconds(t-test, * =p<0.05) Workers were complaining high prevalence of subjective symptoms of Several factors were found influencing fatigue and insomnia (13.5%) , tremor ofblood lead levels in this study significantly; both hands (8.5%) and sleepiness duringyears of employment (p=0.02), previous working and forget-minded (6.4%). Higherexposure to lead (p=0.01), usage of personal exposed group were also complainingprotective equipment (p=0.04), and exposure significant symptoms of weakness of bothto non-neurotoxic chemicals (p=0.04). lower limbs and loss of appetite.However, age, smoking habits, alcoholconsumption and hobbies had no significanteffects to blood lead levels. After controllingfor cofounders, poorer score on the Digitsymbol, Digit backwards, Aiming Pursuitand Trail B Tests were consistentlyassociated with lead exposure. Correlation between the blood leadlevels and the neurobehavioral performancesindicate higher blood lead level tended tohave poorer neurobehavioral performances(Table 4) in Digit Symbol, Digit span,Aiming and Tail B tests. This correlation isalso supported with the linear regression
  6. 6. 6Testing of Hypothesis levels up to 30 µg/ dl (p<0.05)*, thereafter there were no significant correlation between Hypothesis of this study is this two parameters (p=0.66). Lead also hasneurobehavioral test as a diagnostic test to shown it maximum effect at digit symboldetect lead toxicity at low levels in score of 40**. Therefore this analysis cancomparison with overt clinical findings. Few confirm that the hypothesis of this study isclinical problems were identified such as not rejected.hypertension, skin diseases, muscu-losceletal, respiratory, tremor and eye Multiple regression analysesproblems among workers. However, no revealed the significant contribution of yearssignificant findings were found in relation to of employment (YE) together with theblood lead levels (Table 6). blood lead levels to Digit Symbol score (R2= 0.2385, p<0.05). This is consistent with the Further regression analysis were concept of blood lead levels (PbB) reflectingused to assessed the contributions of blood recent exposure and years of employmentlead levels to neurobehavioral tests in reflecting chronic (cumulative) exposureparticular Digit Symbol because of the (Balbus et al. 1995; Rappaport 1991). Thisstrongest correlation’s (r= -0.4348, p<0.05) is shown by the formula;in this study (Figure 1). This analysis hasproven that the digit score symbol werenegatively correlated with the blood lead Digit Symbol = 60.28 - 0.307 PbB - 0.818 YE
  7. 7. 7 Table 6. Clinical findings in relation to blood lead levels Clinical Problems % Positive Mean (sd) PbB (µg/dl) p-value cases Positive cases Normal cases 1. Hypertension 8.4 40.2 (16.0) 40.6 (17.0) 0.94 2. Skin 10.9 38.9 (11.7) 40.7 (17.4) 0.59 3. Musculoskeletal 13.0 42.5 (14.8) 40.2 (17.1) 0.50 4. Respiratory 6.5 43.4 (15.9) 40.3 (16.9) 0.58 5. Eye 2.9 48.8 (7.3) 40.3 (17.0) 0.09 6. Tremor 8.0 40.2 (16.1) 44.6 (24.4) 0.56 7. Anaemia 141 44.4 (21.4) 40.0 (16.0) 0.39Digit Symbol Score100 + . | . | . .. . | ...... . . . . . | .. .. . .. . . . . 50 + .. . . *.. .. ...... ...... .. . . . | . . . . .......... ...... . .. ***. . **| . . .. .. ....... ...... .. . .. .. | . . . . . .. . .. . | . .. . . . + .. . ---+-------------+--------------+--------------+--------------+------- 0 20 40 60 80 Blood lead levels ( µg/dl ) 2 *y= 67.09 - 1.0634 PbB, p<0.05, R = 0.1891 ** Limit value in Digit symbol’s score of 40 *** p= 0.6557Figure 1. Relationship of Digit Symbol’s Score And Blood Lead LevelsDiscussion given higher subjective complaints of weakness of lower limbs and loss of Results from this study has shown appetite in the highly exposed group.that lead can cause dysfunction’s of central This findings of lead toxicity tonervous system in terms of processing speed, neurobehavioral performances and theattention, concentration, memory functions subjective symptom were consistent withand motor steadiness. This is shown in the many other studies (Campara et al. 1984;significant associations between blood lead Seppalainen 1975; Hanninen 1979;levels with Digit Symbol, Digit Span, Trail Grandjean etal 1978; Hogstedt et al 1983,B and Pursuit Aiming Test. Lead also has Schwartz 1993; Valciukas et al. 1978;
  8. 8. 8Williamson & Teo 1986). This study also behavioural electrophysiologicalconfirmed the ability of the neurobehavioral evaluation. Study design and one yeartest in comparison with the overt clinical results. Br J Ind Med. 1984; 41: 352-findings whereby the toxic effect of lead to 361the cognitive functions can be seen at bloodlead levels lower than 30 µg/ dl. Baker E. L. , White R.F. , Pothier L.J. , Due to maximum effect of lead at Berkey C.S. , Dinse G.E. , Traversdigit symbol score of 40, This score can be P.H. , Harley J.P. , & Feldman RG.taken as a limit value between normal and 1985. Occupational lead neuro-abnormal score. Score less than 40 can be toxicity: improvement in behaviouralconsidered as an abnormal score. This effects after reduction of exposure. Brfindings highlight the importance of the J Ind Med: 42: 507-516.neurobehavioral tests which can beincorporated in the medical surveillance Balbus JMK , Stewart W & Bolla KIprogramme of Lead Regulations Malaysia. Cumulative exposure to inorganicFacilities for blood lead measurements are lead and neurobehaviour testnot widely available throughout Malaysia performance in adult: anand the resistance of the workers to this epidemiological review. Occupinvasive procedure which need to be Environ Med 1995; 52: 2-12.routinely conducted, hinder the success ofthe surveillance program. On the other hand Campara P , Andrea FD & Micciliolo R l.the applications of the neurobehavioral tests Psychological performance of workerscan also detect the early toxic effect of lead, with blood-lead concentration belowwhich enhances the prevention strategies the current threshold limit value. Int.before leading to any irreversible damage Arch. Occup. Environ. Health. 1984;(Baker 1985). 53 : 233-246.Acknowledgements Fairulnizal M.N.. Determination of blood lead levels with Graphite FurnaceThis study was supported by a grant from Atomic Absorption Spectrometry. DrugNational University of Malaysia. We would and toxicology laboratory,like to thank the staff and management of Biochemistry division, Institute forboth factories for participating and Medical Research. 1996. (Unpublishedsupporting this study. We are grateful to script).Institute for Medical Research, Departmentof Occupational Safety and Health and Iregen A & Gamberale F. HumanAssociate Professor Dr Abdul Aziz Jemain. behavioural toxicology. Central nervous effects of low-dose exposureReferences to neurotoxic substances in the work environment. Scand J Work Environ Health. 1990; 16 (suppl. 1): 17-25.Arnvig E. , Grandjean P. & Beckmann J. 1980. Neurotoxic Effects of heavy lead Grandjean P , Arnvig E & Beckmann J. exposure determined with Psychological dysfunction in lead psychological tests. Toxicol Lett. 5: exposed workers: relation to 399-404. biological parameters of exposure. Scand J Work Environ Health. 1978;Baker EL , Feldman RG & White RA 4 : 295-303. Occupational lead neurotoxicity: a
  9. 9. 9Hanninen H , Hernberg S & Mantere P.. Seppalainen AM, Hernberg S & Kock R, Psychological performance of subjects Subclinical neuropathy at ‘safe’ levels with low exposure to lead. J Occup of lead exposure. Arch Environ Med. 1979; 20: 683-68. Health. 1975; 30: 180-183. Hogstedt C , Hane M , Agrell A et al. Schwartz BS, Bolla KI, Stewart W et al. Neuropsychological tests result and Decrements in neurobehavioral symptoms among workers with well- performance associated with mixed defined long-term exposure to lead. exposure to organic and inorganic Br J Ind Med. 1983; 40 : 99-105. lead. Am J Epidemiol. 1993; 137 : 1006-1021.Jeyaratnam J. , Boey K.W. , Ong C.N. , et al. Neuropsychological studies on Rappaport S.M. Assessment of long-term lead exposed workers. Br J Ind exposures in air. Ann Occup Hyg. Med. 1985; 42: 173-177. 1991; 35: 61-121.Landrigan PJ. Toxicity at low dose. Br Valciukas JA, Lilis R, Fischbein A et J Ind Med. 1989; 46 : 593-596. al. Central nervous system dysfunction due to lead exposure. Science. 1978; Maizlish N.A , Parra G, Feo O. 201: 465-467. Neurobehavioural evaluation of Venezuelan workers exposed to World Health Organisation. Operational inorganic lead. Occup Environ Med . guide for the WHO Neurobehavioral 1995; 52: 408-414. Core Test battery. 1986. Geneva. WHO. Malaysia. 1994. Factories and machinery (lead) Regulations, Factories and Williamson AM, Teo RKC. Machinery Act, 1967 (Act 139). Neurobehavioural effects of Regulations and Rules. 1984; 267- occupational exposure to lead. Br J 284. Kuala Lumpur. International Law Ind Med. 1986; 43: 374-380. Book Services.Mohamed AAEL , Alla SH & Yousif AAE. Effects of exposure to lead among lead-acid battery factory workers in Sudan. Arch Environ Health. 1986; 41: (4) 261-265.
  10. 10. 10 The Validity-Reliability Study of the Malay Version of Copenhagen Psychosocial Questionnaire (COPSOQ) in Assessing Psychosocial Status in Relation to Nature of Work among Workers Fauziah Nordina2, Quek Kia Fattb, Agus Salim M Banonc a Occupational & Environmental Health Unit, b Medical Statistic Unit, Social and Preventive Medicine Department,Faculty of Medicine, University of Malaya c National Institute of Occupational Safety and Health (NIOSH) MalaysiaAbstract This study aimed to validate the Malay Version of Copenhagen Psychosocial Questionnaire forMalaysian use and application for assessing psychosocial work environment factors. Validity and Reliabilitywere studied in 50 staff nurses of Hospital Selayang. The validity of the questionnaire was evaluated bycalculating the percentage of sensitivity and specificity at the different score level. Both percentage ofsensitivity against specificity were plotted to produce a ROC (Receiver Operating Characteristics) curve, andscore 52 has the highest both sensitivity and specificity was used as an overall index that expresses theprobability that measure the psychosocial problems. For reliability purposes, a descriptive of Test-RetestMean Scores and Paired Sample T-Test and the coefficient-correlation test were calculated. The Test-RetestMean Scores and Paired Sample T-Test for all 26 scales were calculated and showed statistically notsignificant. The reliability of the questionnaire and its 26 scales was assessed by using Pearson (r) (overallquestionnaire r within a range of 0.00 to 1.00). The COPSOQ appears to be a reliable and responsivemeasure of workers for Malaysian use and can be applied for assessing psychosocial work environmentfactors.Keywords: Malay version of COPSOQ, sensitivity and specificity validity, test-retest reliability, Pearson r, Malaysia.Introduction The psychosocial demands of the modern workplace are often at variance with According to an important International the workers’ needs and capabilities, leadingLabour Organizations (ILO) (1975) to stress and ill-health. The most importantresolution, work should not only respect situational factors that give rise toworkers’ lives and health and leave them psychosocial stressors at work arefree time for rest and leisure, but also allow quantitative overload, qualitative underload,them to serve society and achieve self- role conflicts, lack of control over one’s ownfulfillment by developing their personal situation, lack of social support, physicalcapabilities (Steven et al, 1998). stressors, mass production technology,2 Correspondence author: Dr. Fauziah Nordin, email:
  11. 11. 11highly automated work process andshiftwork (Lennart, 1998). Tage S.K., et al (2000) have done a project on the reliability and validity of the Social support increases coping ability assessments among 1858 adult Danishand facilities adaptation. There are five employees, 20 to 60 years of age, 49 perpossible elements of social support, which cent women and the response rate of 62 perare emotional support (example, care and cent. The medium size questionnaire forlove), encouragement (example, praise and work environment professionals has beencompliments), advice (example, useful developed in which all dimensions have ainformation to solve problems), national average of 50. Results deviatedcompanionship (example, time spent with from the average were in a job group ofsupporter) and tangible aid (example, technicians, shop assistants, secretaries,money) (Freda, 1998). domestic helpers, accountants, metal workers, shop assistants, cleaners, drivers, Psychosocial factors which lead to office clerks and food industry workers.stress at work and associated health and When the questionnaire is used for assessingsafety problems, include aspects of the job the psychosocial work environment of aand work environment such as workplace it is possible to compare eachorganizational climate or culture, work roles, department as well as the whole workplaceinterpersonal relationships at work, and the with the national average on all 26design and content of tasks (example; dimensions.variety, scope, repetitiveness). The conceptof psychosocial factors extends also to the Since the study population in eachextra-organizational environment (example; country differed culturally anddomestic demands) and aspects of the sociodemographically from one to another,individual (example; personality, attitudes) therefore a translation version of thewhich may influence the development of questionnaire is require for the assessment ofstress at work (Lennart, 1998). the local population study. Beside the main study, a pilot-study on reliability-validity of The need for valid and reliable the Copenhagen Psychosocial Questionnaireinstruments for assessment of exposures in Malaysian population hopefully mayapplies to the psychosocial field as well as to provide a valid new tool for assessingother fields of work environment research psychosocial factors at work for Malaysianand practice. The Copenhagen Psychosocial use.Questionnaire (COPSOQ), a questionnairefor assessing psychosocial work Study Materialenvironment factors, has been developed bythe Psychosocial Department, National The validity of the study depends on theInstitute of Occupational Health (NIOH) in sampling methodology used, instrumentCopenhagen, Denmark. They have done the reliability and validity, and the design of thereliability and validity of the assessments, study (Steve, 2003). It is important to have aamong adult Danish employees in Danish reliable and valid study instrument beforeversion in a year 2000. The questions of the conducting a study (Abramson et al, 1999).COPSOQ have been translated into English, For this research, since the study instrument,and some of the questions also into the Copenhagen Psychosocial QuestionnaireJapanese. Spanish, German, and Flemish has been developed in other countries; andversions are under development (Tage et al, since each country differed socio-culturally,2000). therefore there is a need for validation of this
  12. 12. 12instrument and to look how acceptable the considered having psychosocial problemsinstruments to Malaysian population. (positive psychosocial status), whereas values below average are considered not Reliability refers to the stability or having psychosocial problems (negativeconsistency of information, which means the psychosocial status). The scales of theextent to which similar information is COPSOQ are formed by adding the points ofobtained when a measurement is performed the individual questions of the scales bymore than once. There are various indices giving equal weights to each question. Thefor reliability measurement. For this scale value is calculated as the simpleresearch, after considering the most practical average. Respondent who answer less thanmeasurement to be used for an interval or half of the questions in a scale is regarded asratio-scale measure questionnaire, the test- missing. If a person has answered at leastretest method will be conducted during the half of the question, the scale value ispretesting period. calculated as the average of the questions answered (Steve, 2003). The Copenhagen PsychosocialQuestionnaire (COPSOQ) is a new tool forassessing psychosocial factors at work andhas been prepared by the National Instituteof Occupational Health (NIOH) ofCopenhagen, Denmark in year 2000. It hasbeen developed in three versions: a longversion for researchers, a medium sizeversion to be used by work environmentprofessionals, and a short version for theworkplaces. The whole concept has beenlabelled “the three-level concept”. The permission to use the questionnairehas been obtained from the author. In orderto make sure the objective to assess thework-related psychosocial status using themedium size version of the questionnaire ismet, the author has emphasized that theresearcher must use either long version ormedium size version of the questionnaire.The short version can only be used by theworkplaces employer, not for researchpurposes. The 95-item medium version ofCOPSOQ has been used in this study. Thequestionnaire has been validatedinternationally and it is a reliable instrumentfor assessment of exposure applies to thepsychosocial field (Steve, 2003). The questionnaire / instruments havebeen developed in the form of Likert Scale.The values above or at average are
  13. 13. 13Study Methods The initial preparation was in Englishversion. The whole set of the questionnairehas been translated to Bahasa Malaysia by aqualified and an expert person in bothlanguage, and the other person translatedback to English version without referring tothe original questions. It is purposely done tomake sure the original content and meaningsof the questionnaire will be the same. The self-administered question-nairewas distributed to 50 subjects consists of 25staffnurses who are shiftworkers and another25 staffnurses who are not doingshiftworkers and were chosen randomly.Data was collected 2 times (Test-RetestMethod) 2 weeks apart. Each respondentwas given a set of complete self-administrated questionnaire in an envelopethat has been distributed by the matron ofHospital Selayang. The completequestionnaire was returned back to thematron after 2 weeks. Raw data obtained was coded andentered into Statistical Package for SocialSciences (SPSS) Version 11.5. The data wasedited and cleaned for double entry andoutliers before analysis could be done.
  14. 14. 14Results Table 1. Validity Test – Percentage Sensitivity and Specificity at Different Score It is highly probable that language is a Levelfactor confounding the validity-reliability of Psychosocial Sensitivity Specificitythe study and it is important to look into it. Scores (%) (%) (%)The initial preparation of COPSOQ 44 100 36questionnaire was in English version. The 46 100 44whole set of the questionnaire has been 48 92 56translated to Bahasa Malaysia by a qualified 50 84 64and an expert person in both language, and 52 76 76the other person translated back to English 54 60 84version without referring to the original 56 48 92questions. It is purposely done to make surethe original content and meanings of the Both percentage of sensitivity againstquestionnaire will be the same and to ensure specificity for those different score levelsbetter reliability for the main study. were plotted to produce a ROC (Receiver Operating Characteristics) curve (Figure 1) Sensitivity and specificity of the and the highest both sensitivity andinstrument had been evaluated by comparing specificity (score 52 percent) are used as anthe scores in exposed group and un-exposed overall index that expresses the probabilitygroup for the psychosocial factors. The that measure the psychosocial problems.validity was established by calculating thepercentage of sensitivity and specificity at The differences between the pairedthe different score level around the average (paired test-retest means) samples,score. However from the result, score 52 calculated using paired sample t-test (Tablepercent is taken as an overall index that 2), shows that mean scores of test and theexpresses the probability that measure the retest were not significant for all scales. Thispsychosocial problems (Table 1). means the variations between scores from the two administrations were insignificant and are thus, reliable and consistent (Loh, 2002). Stres s Sco re 100% 80% 60% 40% 20% 0%120%100% 44 46 80% 48 50 60% 52 54 40% 56 20% 0% Figure 1. ROC (Receiver Operating Characteristics) curve for psychosocial status score.
  15. 15. 15Table 2. Descriptive of Test-Retest Mean Scores and Paired Sample T-Test Test Retest Mean Differences COPSOQ 26 mean-scores mean-scores Mean Diff. 95% CI t Sig. Scales (+SD) (+SD) + SD (Lower-upper (2-tailed) n=50 n=50 Diff.) L UQuantitative 39.00(12.91) 40.50 (10.51) -1.50 (13.81) -5.42 2.42 -0.77 0.446demandsCognitive 37.13 (4.95) 36.87 (4.59) 0.25 (5.20) -1.22 1.72 0.34 0.735demandsEmotional 32.67 (11.88) 33.83 (12.42) -1.17 (14.48) -5.28 2.95 -0.57 0.571demandsDemands for 42.75 (13.14) 42.25 (13.81) 0.50 (14.28) -3.55 4.55 0.25 0.805hiding emotionsSensorial demands 38.63 (11.62) 42.75 (11.32) -4.13 (12.35) -7.64 0.62 -2.36 0.220Influence at work 53.37 (13.78) 54.50 (13.48) -1.13 (12.67) -4.72 2.47 -0.63 0.533Possibilities for 65.75 (11.79) 65.75 (14.41) 0.00 (13.77) -3.91 3.91 0.00 1.000developmentDegree of freedom 24.87 (7.19) 27.25 (7.44) -2.37 (8.17) -4.70 0.05 -2.06 0.045at workMeaning of work 79.16 (10.27) 77.99 (9.33) 1.17 (10.92) -1.94 4.27 0.76 0.454Commitment to 54.87 (24.07) 55.13 (23.17) -0.25 (22.30) -6.58 6.08 -0.80 0.937workplacePredictability 74.00 (11.80) 73.75 (12.44) 0.25 (13.24) -3.51 4.01 0.13 0.894Role-clarity 71.75 (11.24) 72.00 (10.12) -0.25 (12.56) -3.82 3.32 -0.14 0.889Role-conflicts 26.13 (11.27) 27.87 (11.65) -1.75 (11.85) -5.12 1.62 -1.04 0.301Quality of 79.50 (14.40) 82.13 (14.45) -2.63 (13.66) -6.51 1.26 -1.36 0.181leadershipSocial support 72.13 (3.62) 72.37 (3.81) -0.25 (3.78) -1.33 0.82 -0.47 0.642Feedback at work 61.00 (9.99) 61.25 (9.86) -0.25 (10.26) -3.16 2.66 -0.17 0.864Social relations 31.12 (12.27) 29.08 (12.34) 2.04 (14.06) -1.99 6.08 1.02 0.315Sense of 78.57 (15.96) 75.17 (14.78) 3.40 (15.21) -0.97 7.77 1.57 0.124communityInsecurity at work 65.31 (34.16) 64.80 (33.82) 0.51 (36.97) -10.11 11.13 0.10 0.923Job satisfaction 76.66 (9.44) 76.66 (9.86) 0.00 (11.05) -3.17 3.17 0.00 1.000General Health 48.67 (5.75) 49.18 (4.93) -0.51 (6.39) -2.35 1.33 -0.56 0.579Mental Health 34.56 (10.77) 33.76 (11.72) 0.80 (12.47) -2.74 4.34 0.45 0.652Vitality 44.70 (12.22) 43.60 (12.26) 1.10 (13.49) -2.73 4.93 0.58 0.567Behavioural stress 14.25 (8.19) 15.75 (8.68) -1.50(7.63) -3.67 0.67 -1.39 0.171Somatic stress 29.87 (14.07) 28.87 (13.99) 1.00 (14.25) -3.05 5.05 0.50 0.622Cognitive stress 27.00 (14.75) 28.37 (14.52) -1.38 (15.74) -5.85 3.09 -0.62 0.540 * All scales show the mean-difference are not significant at p<0.05
  16. 16. 16 The reliability of the questionnaire and were clearly showed that correlation for eachits 26 scales was assessed by calculating the scale showed statistically significant at thecoefficient-correlation test using Pearson (r) 0.05 level. The strength of the correlation ofwhich showed that overall questionnaire has test-retest is presented in Table 3.value r within a range of 0.00 to 1.00. They Table 3. Reliability of COPSOQ Scales on Malaysian Sample COPSOQ 26 Scales No. of Questions Pearson, r Significant n=50 (2-tailed) Quantitative demands 4 0.319* 0.024 Cognitive demands 4 0.409* 0.003 Emotional demands 3 0.290* 0.041 Demands for hiding emotions 2 0.440* 0.001 Sensorial demands 4 0.421* 0.002 Influence at work 4 0.568* 0.000 Possibilities for development 4 0.462* 0.001 Degree of freedom at work 4 0.377* 0.007 Meaning of work 3 0.383* 0.006 Commitment to workplace 4 0.555* 0.000 Predictability 2 0.404* 0.004 Role-clarity 4 0.312* 0.027 Role-conflicts 4 0.466* 0.001 Quality of leadership 4 0.551* 0.000 Social support 4 0.483* 0.000 Feedback at work 2 0.466* 0.001 Social relations 2 0.348* 0.014 Sense of community 3 0.513* 0.000 Insecurity at work 4 0.408* 0.004 Job satisfaction 4 0.346* 0.015 General Health 5 0.291* 0.042 Mental Health 5 0.388* 0.005 Vitality 4 0.395* 0.005 Behavioural stress 4 0.592* 0.000 Somatic stress 4 0.485* 0.000 Cognitive stress 4 0.422* 0.002*Correlation is significant at the 0.05 level (2-tailed). All correlation is significant for 26 scales.
  17. 17. 17Discussion Research and Development Management Unit for providing the research grant (VotF The validity-reliability of the Malay F0143/2004B) for this study. Special thanksVersion of COPSOQ for 50 staffnurses was for Dr.Noor Akma Md.Yusof, Deputytested. Score 52 percent has the highest both Director of Hospital Selayang and Puansensitivity and specificity is used as an Rokiah Shaari, Matron of Hospital Selayangoverall index that expresses the probability for their great assistance. Especially for Mr.that measure the psychosocial problems. Tage S. Kristensen from National Institute ofThere were no variations between scores Occupational Health, Copenhagen, Denmarkfrom the two administrations of the for permission and invaluable assistancequestionnaire and are thus, reliable and with the copyright COPSOQ questionnaire.consistent. Based on the reliability methods Also, we would like to extend ourin the Survey Methods in Community appreciation to Puan Noor Aizan MahmudMedicine (Abramson et al, 1999) stated that and Puan Nurul Khalbee Abdul Kadir forfor value r below 0.5 suggested poor to their assistance and guidance on Englishmoderate reliability, 0.5 to 0.75 suggested language for this report.moderate to good reliability and above 0.75suggested good reliability. From the findingsabove showed that the questionnaire haspoor to moderate reliability. This could be Referencesattributed to some changes in the scoresduring the test and retest. Since each Steven L.S., Joseph J.H.Jr., Lawrence R.M.,domains comprised from 2 to 5 questions, Lennart L. Psychosocial andtherefore, there is likelihood changes in the organizational factors. Encyclopedia oftotal scores although majority of individual Occupational Health and Safety. ILOitems or questions may not changed much (International Labour Office), Geneva,during test retest. Volume II, 5th Impression 1998; 34.2- 34.3 The validity showed high sensitivityand specificity in the Malay version Lennart L. Psychosocial factors, stress andCOPSOQ. Therefore, it is sensitive and health. Encyclopedia of Occupationalspecific at assessing the psychosocial impact Health and Safety. ILO (Internationalof the workers. The cut off point were 76 for Labour Office), Geneva, Volume II, 5thboth sensitivity and specificity. These cut off Impression 1998; 34.3-34.6points were chosen based on the need thatthe questionnaire to be highly sensitive and Freda L.P. Work and workers. Shiftingspecific. The purpose of having high Paradigms and policies. Womenspecificity is to overcome Type I error workers. Encyclopedia of Occupational(False positive). Health and Safety. ILO (International Labour Office), Geneva, Volume II, 5th Overall, the COPSOQ questionnaire as Impression 1998; 24.2-24.5a whole is a reliable tool to measurepsychosocial work environment factors in a Tage S.K., Vilhelm B. A new tool forMalaysian population. assessing psychosocial factors at work: The Copenhagen PsychosocialAcknowledgement Questionnaire, 2000. Available at: authors would like to express theirgratitude to the University Malaya’s
  18. 18. 18Steve R.T. The validity of a study is our Journal of Community and Applied most important concern. Research Social Psychology, 1993; 3: 235-242 Methodology instructor notes, 2003. Available at: Loudoun R.J., Bohle P.L. Work/Non-work Conflict and Health in Shiftwork: al/2000/resd700/gaybook.PDF Relationships with Family Status and Social Support. Int JournalAbramson J.H., Abramson Z.H., Survey Occupational and Environmental Methods in Community Medicine, Health, 1997; 3(2): 71-77 Epidemiological Research, Programme Evaluation, Clinical Trials. Churchill World Health Organization; Regional Office Livingstone, Fifth Edition1999; 1-14, for the Western Pacific, Manila, 2001. 43-54, 69-78, 89-104, 161-170, 185- Health Research Methodology, A Guide 204 For Training In Research Methods. 2001, Second Edition; 11-41, 71-84,Loh S.Y. Occupational Pressure of Female 147-168, 169-186. Allied Health Professionals. Dissertation for the degree of Master of Kirkwood B. R., Essentials of Medical Counselling, 2002. University Malaya. Statistics. Blackwell Science 1988 ; 76- 84, 87-93, 109-110, 167-170, 191-193.Yawen C., Ichiro K., Eugenie H.C., et al. Association between psychosocial work Martin B., An Introduction to Medical characteristics and health functioning in Statistics. Oxford University Press American women: prospective study. 1995, Second Edition; 27-32, 225-252, British Medical Journal, 2000; 254-264, 331-341. 320(7247): 1432-1436Jeanne A., Rudolf H.M. Work stressors in Health Care: context and outcomes.
  19. 19. 19 Hepatitis B Sero-Conversion Following Immunisation among a Cohort of Rural Australian Health Care Workers Derek R. Smitha,b,3, Julie Portera,c, Peter A. Leggata, Rui-Sheng Wangb a School of Public Health and Tropical Medicine, James Cook University, Townsville, Australia b Department of Hazard Assessment, National Institute of Industrial Health, Kawasaki, Japan c Charters Towers Rehabilitation Unit, Charters Towers, AustraliaAbstract Although vaccination against Hepatitis B Virus (HBV) is highly effective in preventingoccupational transmission among health care workers, not all people develop protective immunity.Furthermore, little is known about sero-conversion in rural areas. We investigated the serology of Anti HBVSurface Antigens (Anti-HBs) among staff at a regional health facility in Queensland, Australia between 1998and 2000. Anti-HBs concentrations were divided into four categories (<10, 10 to 499, 500 to 999, ≥ 1000mIUmL), with <10 mIUmL considered unprotected. Statistical analysis was conducted by intention to treat.At baseline, 91.8% of staff were found to be unprotected against HBV. After the first vaccination, this levelhad dropped to 44.3% and further to 9.8% by the second schedule. However, after 3 vaccinations, 1.6% ofthe original group still had Anti-HBs levels below 10 mIUmL and thus, remained unprotected. Overall, thisstudy has shown that Anti-HBs levels among rural cohorts can be increased by multiple booster vaccinations.Nevertheless, HBV vaccine was not 100% effective, even after 3 doses. Vaccination against HBV is animportant occupational consideration in many areas of health care. Nevertheless, as a certain percentage ofindividuals in rural areas do not successfully sero-convert, alternative vaccination strategies may need to beconsidered.Keywords: Hepatitis B Virus, Regional, Vaccination, Occupational, AustraliaIntroduction (Anti-HBs) following vaccination (Playford et al, 2002). As this group is clearly at risk, Vaccination against Hepatitis B Virus occupational screening for Anti-HBs is(HBV) has been shown to be highly highly recommended (Public Healtheffective in preventing horizontal Association of Australia, 2004). Despite thistransmission (Brotherton et al, 2003). HBV fact, little is known about occupational sero-vaccine is now almost universally offered to conversion following HBV immunizationhospital staff (Queensland Department of and the epidemiology of Anti-HBs levels inHealth, 2004). HBV immunization has been regional health facilities.a condition of employment with QueenslandHealth since 1997 (Murray et al, 2002). Subjects and MethodsDespite a high coverage rate, up to 12% ofhealth care workers may not develop We investigated the nature of Anti-HBsprotective Anti HBV Surface Antigens sero-conversion among staff at a rural,3 Correspondence author: Dr. Derek R Smith, email:
  20. 20. 20mental health facility in Charters Towers, employed as registered nurses, enrolledQueensland, Australia between 1998 and nurses or nursing assistants. Their mean age2000. Anti-HBs levels were established was 51.5 years (SD: 10.5 years). At baseline,using ELISA at Queensland Pathology 91.8% were considered to be unprotectedHealth Services. Concentrations were against HBV. After the first vaccination, thisdivided into the following categories: <10, level had dropped to 44.3% and further to10 to 499, 500 to 999 and ≥ 1000 mIUmL. 9.8% by the second schedule. However,Staff with Anti-HBs levels below 10 mIUmL after 3 vaccinations, 1.6% of the originalwere considered to be unprotected against group still had Anti-HBs levels below 10HBV. Those with a low level (<10) were mIUmL. The serology of Anti-HBs in theautomatically offered a booster vaccination, other concentration ranges was not linear,while those with Anti-HBs levels between although all showed an improvement. The10 and 499 were also offered a booster percentage of staff in the range 10 to 499vaccine to increase their potential level of mIUmL rose continuously throughout theimmunity. Staff were re-tested three months vaccination schedule. A similar effect wasafter the booster vaccination. Three also seen for the concentration range ≥ 1,000vaccination schedules were offered and mIUmL. Interestingly, for 500 to 999statistical calculations were performed by mIUmL, the number levelled off after 2intention to treat (as a percentage of all vaccinations, with no improvement seenstaff). after 3 courses (Refer to Table 1). Over the duration of our study, 8 staff dropped out orResults were lost to follow-up due to resignation, relocation or retirement. A total of 61 individuals were studied.Most (78.7%) were health care workers,Table 1. Anti HBV Surface Antigen Concentrations among Rural Health Care Workers Number and Percentage of Staff at Each Vaccination a Concentration Baseline First Second Third <10 mIUmL 56 (91.8) 27 (44.3) 6 (9.8) 1 (1.6) 10 – 499 mIUmL 0 (0.0) 22 (36.0) 27 (44.3) 28 (45.9) 500 – 999 mIUmL 0 (0.0) 2 (3.3) 3 (4.9) 3 (4.9) ≥ 1000 mIUmL 0 (0.0) 10 (16.4) 19 (31.1) 21 (34.4) b Unknown 5 (8.2) 0 (0.0) 6 (9.9) 8 (13.2)TOTAL 61 (100) 61 (100) 61 (100) 61 (100)a Calculated as a percentage of all staff, with intention to treat (n = 61)b Staff member was either not tested at baseline or lost to follow-upDiscussion HBs levels below the recommended figure. As such, this study has demonstrated that This investigation showed that the Anti-HBs levels among rural health caremajority of rural health staff who were workers can certainly be improved by HBVvulnerable to HBV at baseline had reached vaccination. However, there are a fewadequate immunity by the third vaccination reasons why rural staff may be difficult toschedule. Nevertheless, after three doses vaccinate and follow-up. Firstly, there maysome of our original group still had Anti- be problems accessing appropriate health
  21. 21. 21care facilities. Secondly, HBV vaccinationmay not attract a high priority in regional Referencesareas, where community levels of the diseaseare probably lower than for urban centres. Brotherton JML, Bartlett MJ, MuscatelloThirdly, it may also be difficult to follow-up DJ, Campbell-Loyd S, Stewart K,staff after vaccinations, simply due to the McAnulty JM. Do we practice what wedispersed geographical nature of many rural preach? Health care workers screeningcommunities. Nevertheless, HBV and vaccination. American Journal ofvaccination is highly recommended for all Infection Control 2003; 31: care workers and those at risk ofoccupational exposure to HBV. Health care Queensland Department of Health. QLDworkers whose occupation poses a potential Health Policy for Hepatitis Brisk of exposure to blood or body fluids must immunised against HBV according to Health Infection Control ments/hepb_policy.PDF (accessed JuneGuidelines (Queensland Department of 2004)Health, 2004). HBV immunisation is acondition of employment for Queensland Murray SB, Skull SA. Poor health careHealth workers who have direct patient worker vaccination coverage andcontact, as well as those staff who may be knowledge of vaccinationoccupationally exposed to blood or body recommendations in a tertiaryfluids. By the end of our study, a small but Australian hospital. Australian and Newsignificant proportion of the original group Zealand Journal of Public Health 2002;remained unprotected against HBV. It has 26: 65-68.been previously suggested that as many as12% of vaccinated health care workers may Playford EG, Hogan PG, Bansal AS,not develop protective antibodies in this Harrison K, Drummond D, Lookeregard (Playford et al, 2002). Where DFM, Whitby M. Intradermaladequate Anti-HBs levels are not reached recombinant Hepatitis B vaccine forfollowing three vaccinations, the possibility healthcare workers who fail to respondof HBsAg carriage should be investigated to intramuscular vaccine. Infection(Public Health Association of Australia, Control and Hospital Epidemiology2004). Those who are HBsAg negative and 2002; 23: not respond should be offered furtherdoses of vaccine. Persistent non-responders Public Health Association of Australia.should be informed about the need for Hepatitis B Vaccination Policy.Hepatitis B Immunoglobulin (HBIG) within hours of parenteral exposure to HBV (accessed June 2004)(Public Health Association of Australia,2004). Intradermal administration of HBVvaccine has also been trialled for thosefailing to sero-convert, and may hold somepromise in various health care situations(Playford et al, 2002). Controlled trials ofintradermal HBV vaccine should now beundertaken among rural cohorts whereimmunisation-related sero-conversion doesnot reach 100%.
  22. 22. 22
  23. 23. 23 Off -Site Emergency Planning Hj Mohamad bin Jamil4 Major Hazard Division Department of Occupational Safety and Health (DOSH) MalaysiaAbstract Emergency in a major hazard installation may cause extensive damage to property and seriousdisruption both inside and outside the installation. The overall objectives of an emergency plan are: tolocalise the emergency and, if possible, eliminate it; and to minimise the effects of the accident on people andproperty. The off-site emergency plan is an integral part of any major hazard control system. In manycountries the duty to prepare the off-site plan lies with the local authorities, including Malaysia. Thus, thepreparations of written off-site emergency response planning is required to minimize the impact of majoraccident to the people , property and environment.Keyword: emergency, plan, off-site, MalaysiaIntroduction and an essential part of major hazard control is concerned with mitigating the A major emergency in a major hazard effects of a major accident.installation is one, which has the potential to An important element of mitigation iscause serious injury, loss of life, and damage emergency planning, i.e recognising thatto environment. It may cause extensive accidents are possible, assessing thedamage to property and serious disruption consequences of such accidents and decidingboth inside and outside the major hazard on the emergency procedures, both on siteinstallation. It would normally require the and off-side, that would need to beextensive assistance of outside emergency implemented in the event of an to handle it effectively. Although Emergency plans are likely to bethe emergency may be caused by a number separate for on-site and off-site matters, butor different factors, e.g plant failure, human they must be consistent with other, i.e. theyerrors, earthquake, vehicle crash or must be related to the same assessedsabotage, it will normally manifest itself in emergency conditions. While an on-site planthree basic forms: fire, explosion or toxic will always be the responsibility of therelease. manufacturer, different legislations may Other major hazard controls are place the responsibility for the off- site planconcerned with preventing accidents through elsewhere: for example, the Control ofgood design, operation, maintenance and Industrial Major Accidents Regulationsinspection. Achieving all this will reduce the (CIMAH), 1996 requires the authority torisk of an accident, but it will not eliminate it prepare the off-site plan but not mandatory.altogether - absolute safety is not achievable,4 Correspondence author: Hj.Mohamad bin Jamil, email:
  24. 24. 24Objective of Emergency Planning manufacturer and local authority. Either way, the plan must identify an emergency The overall objectives of an emergency coordinating officer who would take overallplan are: to localise the emergency and, if command of the off-site activities. As withpossible, eliminate it; and to minimise the the on-site plan, an emergency control centreeffects of the accident on people and will be required within which the emergencyproperty. coordinating officer can operate. Elimination will require prompt action An early decision will be required inby operators and installation emergency staff many cases on the advice to be given tousing, for example fire-fighting equipments people living "within range" of the accident -emergency shut-off valves and water sprays. in particular whether they should be Minimising the effects may include evacuated or told to go indoors. In the laterrescue, first aid, evacuation, rehabilitation case, the decision can regularly be reviewedand living information promptly to people in the event of an escalation of the nearby. Consideration of evacuation may include the following factors:Off-Site Emergency Planning (a) in the case of a major fire but without explosion risk (e.g. an oil The off-site emergency plan is an storage tank), only houses close tointegral part of any major hazard control the fire are likely to needsystem. It should be based on those evacuation, although severe smokeaccidents identified by the manufacturer, hazard may require this to bewhich could affect people, property and the reviewed periodically;environment outside the installation. Thus,the off-site plan follows logically from the (b) if a fire is escalating and in turnanalysis that took place to provide the basis threatening a store of hazardousfor the on-site plan and the two plans should material, it might be necessary totherefore complement each other. The off- evacuate people nearby, but only ifsite plan in detail should be based on - those there is time; if insufficient timeevents, which are most likely to occur, but exists, people should be advised toother less likely events, which would have stay indoors and shield themselvessevere consequences should also be from the fire. This latter caseconsidered. Incidents which would have very particularly applies if thesevere consequences yet have a small installation at risk could produce aprobability of occurrence will be in this fireball with very severe thermalcategory, although there will be certain radiation effects (e.g. Liquidfiedevents which are so improbable that it would Petroleum Gas storage);not be sensible to consider them in detail inthe plan. These events might include aircraft (c) for releases or potential releases ofcrashes on to the installation. However, the toxic materials, limited evacuationkey feature of a good off-site emergency may be appropriate down wind ifplan is flexibility in its application to there is time. The decision wouldemergencies other than those specifically depend partly on the type ofincluded in the formation of the plan. housing at risk". Conventional The roles of the various parties who housing of solid construction withmay be involved in the implementation of an windows closed offers substantialoff-site plan are described below. For protection from the effects of aCIMAH regulation, the responsibility for the toxic cloud - while shanty housesoff-site plan will be likely to rest with the
  25. 25. 25 which can exist close to factories, 1976); hazards from potential lost particularly in developing of containment. countries, offer little or no (c) rapid release of limited duration, protection. due to plant failure. e.g fracture of pipe: hazards from toxic cloud, The major difference between releases limited in size, which may quicklyof toxic and flammable materials is that disperse.toxic clouds are generally hazardous down (d) massive release of toxic substance,to much lower concentrations, and therefore due to failure of large storage orhazardous over greater distances. Also, a process vessel or uncontrollabletoxic cloud drifting at, say, 300 meters per chemical reaction and failure ofminute cover a large area of land very safety systems; the exposure hazardquickly. Any consideration of evacuation would affect a wide area.must take this into account. Although a plan should have sufficient The assessment of possible incidentsflexibility built into cover the consequences should produce a report indicating -of the range of accidents identified for the (a) the worse events considered.on-site plan, it is suggested that it should (b) the route to those worst events.cover in some detail the handling of the (c) the time-scale to lesser events alongemergency to particular distance from each the way.major hazard installation. This distance may (d) the size of lesser events if theirbe judge form the result of worst case development is halted.consequence analysis. (e) the relative likelihood of events. (f) the consequences of each event.Identification and Assessment of Hazards Incidents should be assessed in terms of Most major hazard accidents come the quantity of hazardous materials whichwithin the following categories: could be released, the rate of release and the(1) Events involving flammable materials effects of that release – i.e. as thermal (a) major fires with no danger of radiation from a fire or fireball or as a toxic explosion: hazards from prolonged gas cloud - as a function of distance from the high levels of thermal radiation and plant. smoke. Guidance on the dangers of uncommon (b) fire threatening items of plant hazardous substances should be obtained containing hazardous substances; from the suppliers of those substances. hazards from spread of fire, The overall assessment of the major explosion or release of toxic hazard provides the framework for both substances. emergency plans to be drawn up. (c) explosion with little or no warning; hazards from blast wave, flying Aspects to be Included in an Off-Site debris and high levels of thermal Emergency Plan radiation.(2) Events involving toxic materials The CIMAH Regulation has not given (a) slow or intermittent release of toxic the aspects to be included in off-site substances, e.g. from a leaking emergency plans but ideal plan develop at valve. least having the following: (b) items of plant threatened by fire (Chemical Industrials Association,
  26. 26. 26Organisation Assessment Details of command structure, warning Arrangement for:systems, implementation procedures, (a) collecting information on theemergency control centers names and causes of the emergency.appointments of incident controller, site (b) reviewing the efficiency andmain controller, their deputies and other key effectiveness of all aspects of thepersonnel. emergency plan.Communications Role of the Emergency Coordinating Identification of personnel involved, Officercommunication centre, call sign, network,lists of telephone numbers. The various emergency services will be coordinated by an emergencySpecialised Emergency Equipment coordinating officer (ECO) who is likely to Details of availability and location of be a senior police officer but, depending onheavy lifting gear, bulldozers, specified fire- the circumstances, could be a senior firefighting equipment fire boats. officer. The ECO will liase closely with the site main controller.Specialised Knowledge Details of specialist bodies, firms and Role of Major Hazard Installationpeople upon whom it my be necessary to Managementscall, e.g. those with specialised chemicalknowledge, laboratories. The role of major hazard installation managements in off-site emergency planningVoluntary Organisations will be to establish liaison with those Detail of organisers, telephone numbers, preparing the plants and to provideresources, etc. information appropriate to such plans. This will include a description of possible on-siteChemicals Information accidents with potential for off-site harm, Detail of the hazardous substances together with their consequences and anstores or processed on each site and a indication of the relative likelihood of thesummary of the risks associated with them. accidents. Advice should be provided by majorMeteorological Information hazard installation managements to all the Arrangements for obtaining details of outside organisations which may becomeweather conditionals prevailing at the time involved in handling the emergency off siteand weather forecasts. and which will need previously to have familiarised themselves with some of theHumanitarian Arrangements technical aspects of the major hazards Transport, evacuation centres, installation activities, e.g. emergencyemergency feeding, treatment of injured, services, medical departments and also waterfirst aid, ambulances, temporary mortuaries. authorities (if water contamination could be a consequence of an accident).Public Information Arrangements for: Role of the Local Authority (a) dealing with the media-press office. (b) informing relatives. In many countries the duty to prepare the off-site plan lies with the local authorities, including Malaysia. They may
  27. 27. 27have appointed an emergency planningofficer (EFO) to carry out this duty as part ofthe EPOs role in preparing for a wholerange of different emergencies within thelocal authority area. The EPO will need toliaise with the major hazard installation toobtain the information to provide the basicfor the plan. This liaison will need to bemaintained to ensure that the plan iscontinually kept up to date. It will be the responsibility of the EPOto ensure that all those organisations whichwill be involved off site in handling theemergency know of their role and are able toaccept it by having, for example, sufficientstaff and appropriate equipment to covertheir particular responsibilities.Role of the Police The overall control of an emergency isnormally assumed by the police, with asenior officer designated as emergencycoordinating officer. Formal duties of thepolice during the emergency includeprotecting life and property and controllingtraffic movements. Their function includingcontrolling bystanders, evacuating thepublic, identifying the dead and dealing withcasualties, and informing relatives of deathinjury.Role of the Fire Authorities The control of a fire is normally theresponsibility of the senior fire brigadeofficer who would take over the handling ofthe fire from the site incident controller onarrival at the site. The senior fire brigadeofficer may also have a similar responsibilityfor the other events, such as explosions andtoxic releases. Fire authorities should befamiliar with the location on site of all storesof flammable materials, water and foamsupply points, and fire-fighting equipment.They may well have been involved in on-siteemergency rehearsals both as participantsand, on occasion, as observers of exercisesinvolving only site personnel.
  28. 28. 28Rehearsals and Exercises in Off-Site installation, this advice would beEmergency Planning inappropriate because, for example, of the low protection from gas cloud that such Extensive experience in the chemical housing offers, and large-scale evacuationindustry with on-site emergency planning might, be necessary. In these cases, filmhas proved the need and value of rehearsals shows are considered a useful medium forof emergency procedures. passing advise to local people, particularly The organization responsible for where a proportion of them may be unable toproducing the off-site plan should test its read.arrangements in conjunction with on-siteexercises. Table-top rehearsals have proved Conclusionextremely useful in such cases, althoughneeding close control to maintain a sufficient Although identification, prevention andelement of realism in the exercises. mitigation of major accident in place at An essential component of any trial is major hazard installation but risk ofthat of testing fully the various occurrence such accident cannot becommunication links necessary to gather the eliminate. Thus, the preparations of writteninformation needed for overall coordination, off-site emergency response planning ise.g. between major hazard installation and required to minimize the impact of majoremergency control centre and the incident. accident to the people, property and Management of major hazard environment. The most important is to keepinstallation are well placed to advise on the up to date of the establish plan and conductsetting up of rehearsals, and particularly to drill to ensure the plan is working.advise on the scope for an escalation in thedegree of emergency.Information to the Public Experience of major accidents,particularly those involving toxic gasreleases, has shown the importance of thepublic nearby having prior warning of: (a)how to recognize that an emergency isoccurring; (b) what action they should take;(c) what remedial medical treatment wouldbe appropriate for anyone being affected bythe gas. CIMAH regulation requires thoseliving near to the major hazard installation tobe given information, particularly coveringtheir action in the event of an emergency.For inhabitants of conventional housing ofsolid construction, the advice in the event ofan emergency is to go indoors and close alldoors and windows, switch off allventilation air conditioning, and switch onthe local radio for further instructions. Where the large numbers of shanty-dwellers like close to a major hazard
  29. 29. 29References on the 3rd International Conference On Disaster Management. Sarawak,Occupational Safety and Health (Control of Malaysia, 2002. Industrial Major Accident Hazard) Regulations 1996. Elizabeth Girardi Schoen. Emergency Planning and Response.Major Hazard Control, A Practical Manual, ILO, 1988. Ronald H. Mountain, A System for Local Authority Management in a MajorSaari Mustapha and Izani Mohd Zain, Emergency. Disaster Prevention and Prevention, Control and Mitigation Management, Vol 2 No. 1, 1993 Measures of Major Industrial Accidents
  30. 30. 30 Safety in the Construction Industry: Are we Barking at the Wrong Tree? Khairuddin Sulaiman5, Norhayati Mahyuddin Faculty of Built Environment, University of Malaya.Abstract The construction industry is an important industry in the Malaysian’s economy. Much has been saidabout the quality of the product as well as the image of the industry due to the small percentage of localworkers on site. The industry’s welfare and safety record is not at all encouraging. To stop the rot, thegovernment has taken important and significant steps by the establishment of the Malaysian ConstructionIndustry Development Board (CIDB) and the National Institute of Occupational Safety and Health (NIOSH).These efforts have shown some significant positive improvement in the perception and action of thoseinvolved in the industry but we are still far from the standard shown in other developed countries in terms ofsite safety. This paper is to discuss the roles and responsibilities of the key players in the industry be it theclients, consultants or contractors. The focus is on the ‘upstream’ activities i.e. the pre-construction stage,rather than the ‘downstream’ i.e. the construction phase of a project:Keyword: safety, responsibilities, upstream activities, Malaysia.Introduction who is in charge of maintenance, who design the drivers schedule-the answer is the The building and construction industry management. Therefore, in many ways theyis a dynamic and hazardous industry, making are also responsible for the accident. Thisit both unique and challenging to study. This example is taken as to compare what isis due to diverse and complex nature of work happening on construction sites. In the eventtasks, trades and environments, as well as of an accident, all fingers will be pointing tothe temporary and transitory nature of the contractor. There are many contributoryconstruction workplaces in the construction factors to any accident that happens. Thisworkforce. Have you come across an will be discussed further later, but the pointincident involving an express bus causing here is that in any accident on constructioncatastrophic death? In usual case scenario, site, the root cause of an accident must bethe driver is always found guilty of reckless looked into and the contractor or builder isdriving and will be given a few years prison not the only one to be blamed for any injurysentence. On the other hand, what about the or fatality on construction No charge was taken and ofcourse they are covered by insurance and in The theory of accident causationno time they can buy a new bus and hire There are many theories about accidentanother driver. In other words they got off causation but one of the most simple andscotts free! Now let us think, who is in easy to accept theory is the Domino Theory.charge of the company, who hires the driver, This theory has been developed in the5 Correspondence author: Assoc. Prof. Khairuddin Sulaiman, email:
  31. 31. 31Management Operational Unsafe condition Accident Injury structure Area and unsafe action (Loss) Figure 1: Adam’s Dominoes Sequence ( Adapted from: Karim & Lee,1993 )1930’s by a man called Heinrich and has will result in accidents to happen andbeen modified by several others including workers will suffer.Bird (1974) and Adam (1976). Another famous theory is The Failure The above Figure 1 shows the dominoes Initiation Theory by Whittington et alin Adam’s theory which represents the (1992). This theory addresses deficientelements that contribute to the injury policy in the top of organizational level,resulting from an accident. Basically, the suggesting that it stimulates failures in thesource of an accident is at the management lower levels of organization, including in thelevel, example lack of clear safety policy for site and operational levels. The model of thisthe project, and this might triggers choosing theory is as shown in Figure 2 competent contractor who do not care Figure 2 suggests that there four levelsabout safety resulting in dangerous at which failures can occur. In this theory,operation. The unsafe action or operation the failures at higher level will increase the probability of failures at lower Policy Project Site Invidual Accident Failures management management failure event failure failure Figure 2: Adam’s Dominoes Sequence ( Adapted from: Karim & Lee,1993 )level. Failure at top level can be the failure construction starts. This is where the roles ofof the company’s policy which will increase other players in the production processthe probability of failures at the project namely the client and consultants orlevel. Examples of failures at this level are, designers in the upstream activities can bein adequate in training policy or poor related to what is happening on site.methods of procurement. At the project levelthe failures are, lack of planning, poor work Who is responsible?schedule, or choice of inappropriate It is common in the constructionconstruction methods. At the site industry that design and construction bemanagement level, failures can be poor undertaken separately by differentcommunication, lack of supervision or professional organisations. Design of thefailure to adequately segregate work. At constructed facility is normally theindividual level failures can be wrong responsibility of an architect and engineer,equipment or failure to comply with an whereas design of the construction process,agreed method of work. including safety, is conventionally considered to be the contractors’ Therefore causes of accident in responsibility. It is now generallyconstruction site can be linked to many understood in Europe, enshrined infactors that can be traced along the European legislation and, more specifically,production process i.e. even before the since the introduction in 1994 of the