This contains the info on the health hazards associated with the radiation, high temperatures and compressed air like pneumatic drills

1. OCCUPATIONAL DISEASES (VIII)
Group B

2.  Radiation
 Occupational hazards
 Assessing radiation exposure
 Control measures
 Compressed air and its hazards
 Health hazards of high temperature and its management
 Pneumatic drills
 Adverse effects
 Prevention and control measures

3. Occupational hazards of radiation
Radiations are grouped into two groups namely - ionizing and nonionizing radiations,
depending upon the ability to penetrate the tissue, deposit its energy and cause destruction of
the tissue or not respectively.
 Non ionising
 UV rays
 Visible light
 Infrared rays
 Ionising rays
 X-rays
 Gamma rays
 Cosmic rays

4. Non-ionising radiations
A. Ultraviolet Rays:
 Hazards - Since the UV rays do not penetrate the tissues but are absorbed, the
effects are primarily on the skin and eyes. From the natural sources, the effects
are more on the skin and from the artificial sources, the effects are more on the
eyes. The effects depend upon the duration of exposure, intensity of exposure
and the individual susceptibility.
 On the Skin  Short-term effects & Long-term effects.
 Short-term effects: These are immediate effects as follows:
 Melanin pigment which is normally present in Malpighian layer migrates upwards into the
corneum causing darkening of the skin (Suntan)
 Histamine is released resulting in erythema, edema, blisters and even ulcers depending upon
the quantity released.
 Thickening of all layers of epidermis, a protective mechanism.
 Synthesis of vitamin D takes place and rickets is prevented (the last two are useful to the body).
 Long-term effects: These are delayed effects, as follows:
 Degeneration of skin
 Decrease in elasticity
 Cancer of the skin (squamous cell carcinoma, rodent ulcer). For all these effects, black
individuals are less susceptible than white persons.

5.  On the Eyes – (i) From the natural source, the effects are:
 Snow-blindness - common among those skating on the snow, because UV rays reflect from the
snow causing keratitis.
 Burns - on the inside of the nose, common among skaters, because of the reflection from the snow.
 Eclipse blindness - due to direct gazing at the Sun, specially on the solar eclipse.
(ii) From the artificial sources, the effects are:
 Conjunctivitis, keratitis, photophobia
 Flash burns (Welder’s flash)f rom arc welding
 Corneal ulcer (in later stages).
B. Visible Light:
 Hazards
 Poor lighting: Results in eye strain, visual fatigue, accidents, nystagmus (in the mines)
 Bright lighting: Direct light results in glaring, blurring of vision and accidents.
 Direct light from the Sun on the eyes results in scotoma, (a blind-spot) conjunctivitis, keratitis and
photophobia.
C. Infrared Rays:
 Hazards
 On the skin, it causes flushing, burns and even ulcers.
 On the eyes, it may cause cataract.

6. Ionising radiations
Radiation exposure may be internal or external, and can be acquired through various
exposure pathways.
 Internal exposure to ionizing radiation occurs when a radionuclide is inhaled, ingested
or otherwise enters into the bloodstream (for example, by injection or through wounds).
Internal exposure stops when the radionuclide is eliminated from the body, either
spontaneously (such as through excreta) or as a result of a treatment.
 External exposure may occur when airborne radioactive material (such as dust, liquid,
or aerosols) is deposited on skin or clothes. This type of radioactive material can often
be removed from the body by simply washing.
 Exposure to ionizing radiation can also result from irradiation from an external source,
such as medical radiation exposure from X-rays. External irradiation stops when the
radiation source is shielded or when the person moves outside the radiation field.
 People can be exposed to ionizing radiation under different circumstances, at home or
in public places (public exposures), at their workplaces (occupational exposures), or in
a medical setting (as are patients, caregivers, and volunteers).

7. There are acute and chronic effects.
A. Acute effects:
These occur when the body is exposed to heavy (1 Gy) or very heavy (1 to 9
Gy) doses of radiation for short period of time. This is usually accidental. The
condition is called Acute radiation syndrome which occurs in the following four stages:
i. Prodromal stage: Characterized by anorexia, nausea, vomiting, prostration, fatigue
and sweating. Diarrhea and oliguria may occur in fulminating cases. Lasts for 8
to 48 hours.
ii. Latent stage: This is an asymptomatic stage, lasts for 1 to 2 weeks.
iii. Stage of overt illness: Symptoms reappear characterized by fever, anaemia,
leukopenia, pancytopenia, thrombocytopenic purpura, diarrhoea, paralytic ileus,
parasthesia, motor disturbances, ataxia, disorientation, autonomic collapse
indicating involvement or injury to CNS. Lastsfor3weeks.
iv. Recovery stage: Lasts for about 15 weeks. Exposure tomassive doses of more
than10Gymay cause death, in a day or two from cerebral edema or cardiac
failure.

8. B. Chronic effects: These are the delayed effects. Grouped into
two groups somatic and genetic.
I. Somatic effects:-Earliest effect is on the eyes, resulting in
cataract. Skin lesions appear late. They include erythema,
edema, blisters and ulcers. Still later hyperkeratosis and
atrophy of the sebaceous glands occur. Skin lesions are
common with b-particles and cataract with neutrons. The other
delayed somatic effects are cancer of the lung, skin, blood,
aplastic anemia and tumor induction. These delayed somatic
effects are seen among those exposed to less than 1Gy over
a long period Of time.
II. Genetic effects: These occur when gonads are exposed and
chromosomes are injured.
 Chromosomal mutations result in still-births, congenital defects,
neonatal deaths and even sterility
 Point mutations are due to injury to genes resulting in Down’s
syndrome, Huntington’s chorea, polycystic kidney, hemophilia.
Thus, somatic effects are seen within the life-span of the
affected individual, whereas genetic effects are seen in the
next generation.

9. Assessment of radiation exposure
 By measuring the radiation level around a
person's body using a Geiger counter, a safety
officer can approximate that person's
absorbed dose. A more sophisticated measure
of radiation exposure, called the effective
dose, accounts for the harmfulness of the
specific type of radiation present.
 Biodosimetry is the direct measurement of
radiation induced biological or physical effects
within the body to assess the radiation dose to
an individual. Such measurements include
certain blood tests, urine and faecal
radionuclide assays, and whole body and
specific organ counts.

10. How is radiation exposure measured and assessed?
 Dosimetric aspects:
To evaluate the risk contribution from scans performed with
security scanners based on technologies using ionising
radiation
Dose concept Organ doses
Effective
doses
Morbidity and
mortality data
Dose
determination

11. Prevention and control of radiation hazards
A. Primary Prevention: Primary prevention is by the
following measures:
I. Safety of the Machine:
 Machine should be of approved quality and
installed properly.
 Periodical servicing and proper maintenance.
 Use of efficient filters so that unwanted radiations
are excluded.
 Operated on high kilo-voltage with fast films and
image intensifier so that exposure is reduced to
minimal dose.
 The machine is connected to the door in such a
way that it should stop functioning automatically,
the moment the door is opened accidentally.

12. II. Safety of the Worker:
 Preplacement examination of the worker to exclude contraindications if
any for fitting the job to the worker (ergonomics).
 Health education about radiation hazards and avoiding unnecessary
exposure.
 Regulation of exposure so that exposure is limited, by provision of holidays
and recreation and also by rotation of the worker.
 Personal protection by wearing:
 Filter respirators/masks
 Spectacles with reflecting mirrors; visors while doing arc welding.
 Lead aprons, lead gloves, (lead reduces the intensity over 90%).
 Pocket dosimeter (This is a monitoring device, worn on the collar by the
worker, same dosimeter to be worn by the same individual, which records
the
 cumulative dose of the radiation received by that individual. It is sent to
Atomic Research Center,
 where it is analysed and report is given about the dose of radiation
received. If the individual has received radiation more than the permissible
limit of 5 rads per year, clinical examination and differential count is done).
 Use of lead boxes to keep radium needles and radioactive isotopes.
 Use of long forceps to handle radium needles.
 Use of shield between the source and the recipient.
 By avoiding eating or drinking in the working room.

13. III. Safety of the Environment: Air, soil and water should be clean and pure.
They should be free from pollution.
IV. Other Measures: Such as specifications of the room of cobalt unit or X-ray
machine and disposal of radioactive wastes.
a) Specifications of the room of cobalt unit and X-ray machine:
 Walls must be thick and made of concrete.
 Roof must be high.
 Wet mopping of floor to be done (Good house keeping).
 Vacuum cleaning of the room
 Lead protected doors.
 Lead glasses to be used for windows.
 Exhaust system of ventilation
 Controlling machine should be as far away as possible from the worker.
 Enclosure of the machine, ventilated hoods, splash-trays control the release
of dust in the environment.
b) Disposal of radioactive wastes:
 By putting in a steel case and embedding deep in the sea bed at 1800 mts
deep
 By putting it in an underground concrete seal
 By burning in a special incinerator provided with
 filters and very tall stacks.

14. B. Secondary prevention:
I. Early diagnosis/detection: It is done by
periodical analysis of dosimeter.
II. Treatment:
 For leukemia: By predinsolone, vincristine, daunorubicin,
arabinosyl cytosine.
 For bone marrow aplasia: By antibiotics and blood
transfusion.
 For bone sarcoma: By amputation followed by
chemotherapy.
III. If the individual is accidentally exposed and the
radioactive material has entered the system, that
person is immediately decontaminated as
follows:
 If implanted, the skin is excised, the radioactive material is
removed, the area is washed with hot water and soap
followed by application of citric acid.
 If swallowed, the adsorbants such as Prussian blue or ion
exchange agents are given followed by emetics and salt
purgatives. Diethylene triamene penta acetic acid (DTPA)is
effective.

15. Compressed air and its hazards
 Compressed air is a gas or combination of gases, that has
been put under high pressure than the air in the general
environment or air kept under a pressure that is greater than
atmospheric pressure. It is used for various purposes such as-
 vehicle propulsion
 Energy storage
 Air brakes, including railway braking system, road braking
system
 Underwater diving, for breathing and to inflate buoyancy
devices.
 Refrigeration using a Vortex tools
 cleaning dust and small debris in tiny spaces etc.

16. Hazards
 compressed air accidentally blown into the mouth
can rupture the lungs, stomach or intestine.
 ear embolism
 rupture ear drums or organs
 dislodged eye balls
 high noise can result in temporary or permanent
hearing loss.
 skin wounds
 Decompression sickness: often called generalized
barotrauma or bends, occurs when nitrogen
dissolve in blood and tissue by high pressure and
forms bubbles as pressure decreases leading to
pain and fatigue in muscles and joints. Commonly
seen in Scuba or deep diver's.

17. Health hazards of high temperatures
 Heat is the common physical hazard in most industries. Eg:
 Radiant heat is the main problem in foundary, glass and steel industry.
 Heat stagnant is the principal problem in jute and cotton textile industry.
 Physical work under such condition is very stressful and impairs the health and
efficiency of the workers.
 The direct effect of heat exposure are:
i. Heat syncope
ii. Heat cramps
iii. Heat exhaustion
iv. Heat stroke
v. Heat hyperpyrexia
vi. Burns
vii. Local effects like prickly heat

18.  Heat syncope: This is a common ill-effect of heat. In its
milder form ,the person standing in the sun becomes pale
,his blood pressure falls and he collapse suddenly. There is
no particular rise in body temperature. The condition results
form pooling of blood in lower limbs due to dilatation of blood
vessels, with the result that the amount of blood returning to
the heart is reduced, which in turn is responsible for lowering
of blood pressure and lack of blood to the brain.
 Heat cramps: Heat cramps occur in persons who are doing
heavy muscular work in high temperature and humidity.
There are painful and spasmodic contractions of skeletal
muscles. The cause of heat cramps is loss of sodium and
chloride in the blood.
 Heat exhaustion: Caused primarily by the imbalance or
inadequate replacement of water and salts lost in
perspiration due to thermal stress leading to circulatory
failure. The symptoms primarily are dizziness, weakness and
fatigue i.e. those of circulatory distress.

19.  Heat stroke: There will be failure in the
heat regulating mechanism, resulting in
the high temperature of the body, delirium,
convulsions, partial or total loss of
consciousness. Skin is dry and hot. Death
may occur due to hyperkalemia cause of
which is not known, probably due to
release of potassium from RBCs which
are injured by heat. Treatment is by rapid
cooling in ice water bath.
 Heat hyperpyrexia: It is characterized by
failure in heat regulating mechanism
without the feature of heat stroke. It may
also proceed to heat stroke.

20. CONTROLAND MANAGEMENT FOR WORKERS
WORKING IN HIGH HEAT CONDITION:
A. Administrative controls
 Acclimatization: Allow sufficient acclimatization period
before full workload.
 Duration of work: Shorten exposure time and use frequent
rest breaks.
 Rest area: Provide cool (air-conditioned) rest-areas.
 Water: Provide cool drinking water.
 Pace of Work: If practical, allow workers to set their own
pace of work.
 First aid and medical care: Define emergency procedures.
Assign one person trained in first aid to each work shift.
Train workers in recognition of symptoms of heat
exposure.

21. B. Clothing: Wear loose clothing that permits sweat
evaporation but stops radiant heat. Use cooled protective
clothing for extreme conditions.
C. Engineering controls:
 Stop exposure to radiated heat from hot objects
 Insulate hot surfaces, use reflective shields, aprons, remote
controls.
 Reduce convective heat gain: Lower air temperature.
Increase air speed if air temperature below 35°C. Increase
ventilation. Provide cool observation booths.
 Increase sweat evaporation: Reduce humidity. Use a fan to
increase air speed (movement).

22. Pneumatic drills and pumps
ADVERSE EFFECTS OF VIBRATION TOOLS LIKE PNEUMATIC DRILLS:
 Ergonomics- Vibration, awkward postures and forceful and repeated
exertions may all be associated with using these tools. The excessive
vibration can lead to loss of control of tool, increased fatigue while using the
tool and serious often permanent condition called occupational vibration.
 Noise.
 Flying objects.
 Workers can be directly injured by pneumatic power tools when-
 Attachments or fasteners are not secured properly and fly off the tool.
 The operator misses the intended surface and a nail or staple strikes a
bystander.
 Hoses are accidently disconnected from the tools.
 Hoses fail.
 Tools are accidently activated.

23. PREVENTION AND CONTROL
 Reduce transmission of vibrating energy to hand.
 Workers and bystanders should have personal protective equipment or screens.
 Pneumatic impact tools should have safety clips or retainers that prevent dies and
tools from being accidently expelled from barrel.
 All handheld pneumatically powered tools used for drilling nails, staples etc. that
operate at 100psig or more line pressure should be equipped with a safety device that
prevents the tool from operating unless the muzzle is in contact with the surface.
 All hose connections on pneumatic power tools should be secured by positive locking
device to prevent accidental disconnection.
 To prevent damage to hoses make sure that manufacturers safe operating pressure
for hoses, pipes, valves, filters and other fittings are not exceeded.
 Pneumatic nailers and staplers must be disconnected from their air supply at the tool
when not in use or unattended.

24. References
 AH Suryakantha’s textbook of PSM
 K Park’s PSM
 www.nioh.org
 www.bing.com/images