Group B of the Mechanical Engineering students at Takoradi Polytechnic presented on Occupational Health and Safety. They discussed hazardous symbols, types of hazards, effects of radiation, fire safety including classifications of fires and appropriate fire extinguishers, and safe lifting techniques. The group identified potential sources of workplace fires and their remedies. They demonstrated the proper use of fire extinguishers and signals for operating cranes safely.

1. TAKORADI POLYTECHNIC
(SCHOOL OF ENGINEERING)
(HND) MECHANICAL ENGINEERING 1A
GROUP B
PRESENTATING
ON
[OCCUPATIONAL HEALTH AND SAFETY (2]

2. GROUP B -MEMBERS
NAME INDEX NUMBER
McCLEMENT INTARMAH 07128315
OBRO DAVIS 07128320
OPOKU EVANS 07128527
KUMI DESMOND 07128317
KOOMSON SAM BISMARK 07128316
MINTA BENJAMIN
MUTIU ISMAEL
DOGBATSEY MAWULI 07128537
GYEWU ANDREWS 07128314
ESSIEN SAMUEL
QUARTEY MILT 07128370

3. At the end of the presentation, students
Identify hazardous and industrial symbols at the work shop
Categorize effective and safe methods of how to move equipment
Exhibit correct body positions for manual lifting whilst following
appropriate methods for manual or mechanical lifting
Spot the potential sources of fire and their corresponding effective
remedies
Select the effect of fires on employee, employer, economy and society
Recognize fire fighting equipment, their selections and uses based on a
particular class of fire.

4. INTRODUCTION
Occupational health and safety is a cross disciplinary
area concerned with the ensuring of safety, health
and welfare of the people engaged in the occupation.
The main focus of this presentation is to bring to the
awareness of the class the hazards they could
encounter at the work place and their respective
remedies.

5. SOME HAZARDOUS TERMS
HAZARD : Hazard is a term associated with things or incidence
that are likely to cause damage and injury in a given environment and
to a person respectively.
SYMBOLS: A perceptible indication of something not
immediately apparent.
(as a visible clue that something could happen)
HAZARD SYMBOLS: are recognizable symbols designed to
warn about hazardous materials or locations.
DANGER: They are anything that posses a threat to the human
and environment.

6. HAZARDOUS SYMBOLS
TRIPPING RESTRICTION Toxic :can cause
poisoning through
ingestion, inhalation,
absorption through
tissue.
Fig. 1.1 A hazardous symbols 6

7. Dangerous substances Corrosive: can
to environment cause damage to
the skin and the
eyes.
Fig 1.1 B

8. Explosive ;substances
will explode giving the Harmful irritant
right conditions.[petrol substances can
and gases(LPG). produce harmful
effects
Fig 1.1 C

9. RADIATIONS
(when electromagnetic waves travel through a medium )
Some radiation symbols and their effect at the workplace
Non-ionizing
Ionizing
Radioactive radiation: can also
radiation: can
sign: causes cause damage to the
damage to cause damage to
body tissues if
body tissue and
tissues when exposed to it much
blood cells
induce to the
body Fig. 1.2 Radiation symbols

10. Magnetic field: Laser beams High voltage
worker should be
careful with
magnetic objects
Fig 1.2 B

11. TYPES OF HAZARD
There are four main types of hazards:
 Physical hazards:
 Biological hazards
 Ergonomic hazards
 Chemical hazards:

12.  Chemical hazards - This means polluting the environment with
chemicals e.g. dust, gases, vapor, fume.
 Biological hazards -This can be transported by the following
fungi, moulds, bacteria's, viruses.
 Physical hazards – They are caused by physical means.

13. EFFECTS OF RADIATIONS ON THE
BODY
1. (Hair) The losing of hair quickly and in clumps occurs
with radiation exposure at 200 rems or higher.
2. (Brain ) Can cause damage to the brain when exposure is
5,000 rems or greater
3. (Thyroid) radioactive iodine can destroy all the part of
the thyroid by taking potassium iodine from the tissues
4. (Blood system) when exposed to around 100 rems, the
blood lymphocyte cell will be reduced, leaving the person
more susceptible to infectious

14. 5. (Heart) Intense exposure to radioactive material at 1,000 to 5,000 rems
would cause immediate damage to small blood vessels and probably
cause heart failure and death directly.
6. (Gastrointestinal tract) Radiations cause damage to the intestinal tract
lining, cause nausea, bloody vomiting and diarrhea. This is occurs
when the victim's exposure is 200 rems or more.
7. (Reproductive tract) Because reproductive tract cells divide rapidly,
these areas of the body can be damaged at rem levels as low as 200
rems when exposed for a long period.

15. FIRE
Fire : is a chemical reaction called combustion, usually oxidation
resulting in release of heat and light.
For fire to occur three element of fire have to come together.
1. FUEL
2. OXYGEN
3. HEAT

16. THE FIRE TRIANGLE
Fig 1.3shows the fire triangle

17. FIRE SENSORS
Fire alarm
Fig.1.4 fire sensors

18. Addressable simplex smoke
detector
Flame detector
Fig.1.4 b. smoke detectors
Smoke detector

19. FIRE FIGHTER
Fire fighter: They are experts who has been trained in the methods
of fighting fire.
Their goal is to save life, property and the environments.
Firefighter’s duties include public education and conducting fire
inspections.

20. FIRE FIGHTING EQUIPMENT
They are the needed equipment that aids in effective quenching of
fire outbreak.

21. SOME FIRE FIGHTING EQUIPMENT
Fire gun
Protective clothing
Fig 1.5 A shows fire fighting equipment

22. Extinguisher
Hood
Fig 1.5 b

23. CLASSIFICATIONS OF FIRE
 CLASS A:
This involves combustible materials. Examples; wood, paper etc
 CLASS B:
This involves flammable liquids. Examples; gasoline, solvent.

24.  CLASS C:
This involves electricity in object. Example; electric motor, generators
 CLASS D:
This involves certain combustible metals and chemicals. Examples;
sodium , magnesium
 CLASS F: fires which involves high temperature cooking oils or large
catering establishment or restaurants.

25. TYPES OF FIRE EXTINGUISHERS
The various fire extinguishers are;
1. Water or foam fire extinguisher
2. Carbon dioxide extinguisher
3. Dry powder extinguisher
4. Special fire extinguisher

26. HOW TO USE A FIRE
EXTINGUISHER
The acronym PASS helps a fire fighter to
use the fire extinguisher effectively
 Pull
 Aim
 Squeeze
 Sweep Fig 1.6 .shows how to a fire extinguisher

27. CLASS A: This can be
quenched by using water or
foam that will remove the
heat from the source .
Fig. 1.7 Shows the classes of fire with respect to
their extinguisher
Foam Fire Extinguisher

28. CLASS B: This can be
quenched by using dry
chemical or carbon
dioxide
Carbon Dioxide Fire Extinguisher Fig. 1.7 a

29.  CLASS C: This can be
quenched by using a dry
powder extinguisher such as
ammonium phosphate
Dry powder extinguisher Fig.1.7 b

30. • CLASS D: This can be
quenched by using
special extinguisher
powder
Special fire extinguisher Fig.1.7 c

31. POTENTIAL SOURCE OF FIRE
 NATURAL SOURCE
 ARTIFICIAL SOURCE
NATURAL SOURCE
They are the source of fire caused by nature.
Example: volcano and sun.

32. ARTIFICIAL SOURCE
These are source of fire cause by artificial means.
They include:
 Naked flames: From smoking materials, cooking appliances, space
heating / drying appliances.
 External sparks: from grinding metals, welding, impact tools,
electrical switch gear

33.  Internal Sparks: from electrical equipment (faulty and normal),
machinery, lighting.
 Hot surfaces: From lighting, cooking, heating appliances, brazier, tar
boilers, plant and machinery, poorly ventilated equipment, faulty and/
or badly lubricated equipment, hot bearing and dry belt
 Static electricity: causing significant high voltage sparks from the
separation of materials such as unwinding plastic, pouring highly
flammable liquids, walking across insulated floors, or removing
synthetic overalls

34. CAUSES FIRE OUTBREAK
Smoking Kitchen fire Candle
Fig.1.8 causes of fire outbreak

35. SOME REMEDIES OF POTENTIAL
SOURCE OF HEAT AND FIRE
 One should exhibit the habit of avoiding smoking whiles at the
work place
 All naked flames must be placed at positions that will not catch fire
easily
 All combustible liquids must be kept in a metal containers
 Making sure that containers with flammable liquids are tightly
closed. Example gasoline.

36. EFFECTS OF FIRE
1. EMPLOYEE 1. The employee losses his/her
job incase the company is closed
down
2.Loss of life if he is highly
involved incase of fire outbreak
2. EMPLOYER 1.The employer losses his/her
capital invested in the business
2.Loss of personnel at the
workplace

37. 3. ECONOMY 1. The economy losses financial
assistance from the company
2. Low productivity
4. SOCIETY 1. Cause depletion the ozone
layer
2. Cause pollution to the
environment

38. METHOD OF MOVING EQUIPMENTS
Come close to
the equipment Fig.1.9 A method of moving equipment
and stand firmly

39. WRONG WAYS OF MOVING
EQUIPMENT
Pushing with one hand is
There will be more not effective and there will
stress at the knee be more pain at the wrist
and waist and the arm
Fig.1.9 B wrong ways of moving equipment

40. Fig 1.9 c
Wrong position of the hand

41. BODY POSITION IN MANUAL
LIFTING
Bring your hand
Stand close Relax the body closer to the object
to the object and bend your and bend your waist
knees a bit Fig. 2.0 A

42. Try to lift the load by
Squat and place your
stretching your legs
hand beneath the object
Fig 2.0 b

43. MECHANICAL LIFTING
CRANE
This is a large machine that
moves heavy things by
lifting them in the air.
OR
Fig. 2.1 mechanical lifting
A kind of large bird with a long
neck and long legs.

44. FACTORS TO BE CONSIDERED
WHEN LIFTING A LOAD WITH A
CRANE
 Competent and certified operator
 Trained and certified rigger
 Inspected and certified lifting equipment
 Must not be over loaded
 Isolate the area to avoid an unauthorized entry

45. PROCEDURE IN LIFTING A LOAD
WITH A CRANE
 Place a short bar under the load
 Tie the load with a crane belt
 Hang the belt on the hook securely

46. VIDEO SHOWING THE OPERATION OF A
CRANE

47. CRANE SIGNAL CHART
Stop Emergency stop
The rigger is indicating that the operator
should stop the crane.
Fig.2.2 A. crane signal chart

48. Up Lower

49. Move slowly Move left
49

50. hoist Whip line
50

51. CONCLUSION

52. QUESTIONS
1. Define fire and give some examples of fire fighting
equipment.
2. State and explain the classifications of fire and give two
examples each.
3. Define hazard and sketch some hazardous symbols.

53. REFRENCE
 http//:wikipedia.com
 http//:goggle.com
 http//:e-how.com
 Williams A. Schuster (small engine technology) Edition 2