1) The document presents on safety measures in microbiology, focusing on the safe handling and use of disinfectants. It discusses the testing and effects of common disinfectants like phenol on microorganisms. 2) General safety practices for working in a microbiology laboratory are outlined, including proper attire, hygiene, and hazard protocols. 3) Adhering to safety principles when using disinfectants and in microbiological work is emphasized to avoid accidents and protect workers, equipment, and the environment from harm.

1. STUDENT INDUSTRIAL TRAINING WORK EXPERIENCE
SCHEME (SIWES) PRESENTATION.
B Y
A G G R E H E R H O V W O N P E T E R
( U 2 0 11 / 5 5 5 5 0 1 0 )
U N I V E R S I T Y O F P O R T H A R C O U R T
M I C R O B I O L O G Y,
C O O R D I N AT O R
D R ( M R S ) C . M B A K W E M - A N I E B O
C O M PA N Y
I N T E G R AT E D L O G I S T I C S S E R V I C E S ( I N T E L S ) N I G E R I A LT D
D E PA R T M E N T AT TA C H E D
Q U A L I T Y H E A LT H S A F E T Y A N D E N V I R O N M E N T ( Q H S E ) . M AY 2 0 1 5 .1

2. S A F E T Y I S N O A C C I D E N T ; P . A . U . S . E . . . . . T H I N K S A F E T Y 2

3. TOPIC
SAFETY MEASURES IN MICROBIOLOGY TAKING DISINFECTANTS
(CHEMICAL) AS A CASE STUDY.
AIMT O U N D E S T A N D T H E E F F E C T O F D I S I N F E C T A N T O N M I C R O O R G A N I S M S A N D T H E S A F E T Y
P R I N C I P L E S I N V O L V E I N I T ’ S ( D I S I N F E C T A N T S ) U S A G E .
S A F E T Y I S N O A C C I D E N T ; P . A . U . S . E . . . . . T H I N K S A F E T Y 3

4. OUTLINE.
 INTRODUCTION
 AN OVERVIEW OF DISINFECTANTS
 TESTING OF DISINFECTANTS
 THE IN-USE TEST
 CHART DIAGRAM
 EFFECT OF DISINFECTANT ON MICROORGANISM
 EFFECT OF PHONOL ON BACTERIA CELL MEMBRANE
 SAFE HANDLING OF DISINFECTANTS
 GENERAL SAFETY PRACTICES IN MICROBIOLOGY
 CONCLUDING REMARKS.
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5. INTRODUCTION
 Safety in a brief definition can be defined as the condition of being safe;
it is the control of recognized hazard to achieve an accepted level of risk.
 Hazard is a situation that poses a level of threat to life, health or
environment.
 Risk is a child born of hazard, it is defined as the potential of losing
something of value. it involves uncertain danger.
 Safety measures in microbiology are activities and precautions taken to
improve safety i.e. reduced risk related to human health and environment
while carrying out a microbiological operation or activities.
 Precautions are actions taken in advance to protect against possible
danger, failure or injury. 5

6. AN OVERVIEW OF DISINFECTANTS.
 Disinfectant is a chemical agent that kills or inactivates pathogenic
microorganisms on inanimate object (s) to prevent and reduce infection risk.
 The level of disinfection achieved depends on the contact time, temperature,
type and concentration of the active ingredient, the presence of organic matter,
the type and quantum of microbial load.
 CHARACTERISTICS OF A GOOD DISINFECTANT
 It is non toxic and has a wide spectrum.
 Non irritating and non corrosive.
 It does not corrode instruments.
 It does not discolor materials and it is speedy in action.
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7. TESTING OF DISINFECTANTS.
 Disinfectants are known to loose their ability when left standing and in
presence of organic matter.
 It results to an unsafe act when such disinfectants are used.
 For this reason disinfectants are meant to be checked or tested periodically.
 METHODS OF TESTING DISINFECTANTS
 KOCH’S METHOD
 IN-USE TEST
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8. THE IN-USE TEST
 The disinfectant is diluted 1 in 10 by mixing 1 ml of the disinfectant with 9 ml of
sterile nutrient broth.
 Ten drops of the diluted disinfectant (each 0.02 ml) is placed on two nutrient
agar plates.
 One plate is incubated at 37 OC for 3 days while the other is held at room
temperature for 7 days.
 The number of drops that yielded growth is counted after incubation.
 If there is growth in more than five drops on either plate, it represents failure of
the disinfectant.
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9. CHART AND DIAGRAM
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Fig. 2. A pictorial
demonstration of the in-
use test of Maurer (1985).
Fig. 3. A practical
demonstration of the in-
use test technique.

10. EFFECT OF DISINFECTANTS ON MICROORGANISMS.
EXAMPLE OF
DISINFECTANT
MODE OF ACTION ON
MICROORGANISM
EXAMPLE(S) OF
ORGANISM
AFFECTED
PARACETIC ACID IT OXIDISES AND
DENATURES PROTEINS
AND LIPIDS OF
MICROORGNISMS
Bacillus species,
Giardia lablia,
Mycobacterium
tuberculosis.
PHENOLS (LYSOL) IT ACTS SPECIFICALLY
ON THE CELL
MEMBRANE AND
INACTIVATES
INTRACYTOPLASM
ENZYMES
Candida species,
Aspergillus species,
Pseudomonas sp.
IODINE IT BLOCKS THE
TRANSPORT OF
ELECTONS THROUGH
Staphylococcus aureus,
Salmonella typhi,
Pseudomonas
TABLE. 1. A TABLE SHOWING THE EXAMPLES OF DISINFECTANTS
AND THEIR MODE OF ACTION(S).
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11. EFFECT OF PHENOL ON BACTERIA CELL
MEMBRANE
Fig 4. Action of phenol on bacteria.
Extracted from Sridah Rao Kn. 2(32), 1998,
STERILIZATION AND DISINFECTION.
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12. SAFE HANDLING OF DISINFECTANTS
 Wash surfaces first with warm and soapy water and rinse with clean water.
 Read the label carefully before using a disinfectant and note that they are
flammable.
 Only use the disinfectant in a well ventilated areas and be aware of the handling
precautions and procedures.
 Apply disinfectants to all areas and allow for sufficient contact time before rinsing.
 Do not miss with hypochlorite cleaners, acid or acid cleaners. The chlorine fumes
are highly toxic.
 Finally, do not apply disinfectant to the mouth or bodily surfaces. They can cause
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13. GENERAL SAFETY PRACTICES IN MICROBIOLOGY .
 Always have a tool box meeting before carrying out any laboratory activities
and during the operation, endeavor to carry out the step back 5×5 process.
 On the first day, familiarize yourself with the location of the eye wash station,
safety shower, campus phone, muster point, emergency door and the fire
extinguisher.
 Do not eat, drink, smoke or apply cosmetics in the laboratory.
 Always wash your hands thoroughly with soap and water before and after using
the laboratory
 Disinfect, clean up your bench and apparatus before and after usage.
 Label all culture and solutions properly.
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14.  Come properly well dressed to the laboratory. This implies the wearing of
laboratory coats, eye goggles, ear muff, closed toes shoes etc.
 Be careful when using the Bunsen burner because it produces open flame
which is a safety hazard.
 Make sure that the pointer of the laboratory fire extinguisher is always on the
green band.
 Switch off all electrical appliances when not in use and do not take water close
to them.
 Properly dispose off wastes (hazardous) that pose environmental hazards and
risk. S A F E T Y I S N O A C C I D E N T ; P . A . U . S . E . . . . . T H I N K S A F E T Y 14

15. CONCLUDING REMARKS.
 The importance of adhering to safety principles, practices and precautions by the
microbiological worker cannot be overemphasized.
 Disinfectants are safety hazards though they are lethal to microorganisms.
 Disinfectants should be properly managed to avoid the microbiological worker being exposed to
unnecessary risk that may later lead to an accident and cause future problem(s).
 A work cannot be said to have been achieved successfully when the personnel involved in the
work, properties and the environment is not in a safe condition.
 Safety is a very serious matter because it involves the loss of lives and properties.
 Workers and students should be encourage to undergo safety trainings and to always adhere to
safety principles.
 Indeed, SAFETY IS NO ACCIDENT, P.A.U.S.E…..Think Safety.
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16. THANK YOU
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