Chemicals are the most common and significant health hazards and Chemicals can be hazardous for numerous reasons and can combine with other chemicals to make new hazards. Therefore All hazards must be taken into account when using and storing chemicals. # Understand that chemicals hazards. # Understand that safe storage is an important issue. # Understand that many chemical injuries result from improper storage. # Know four basic rules of chemical safety. # Be aware of the categories of dangerous chemicals and appropriate safety precautions.

1. Chemical Hazards/
Safety

2. Chemical hazards
 Chemicals can be
hazardous for numerous
reasons and can combine
with other chemicals to
make new hazards
 All hazards must be
taken into account when
using and storing chemicals.

3. Objectives
 Recognize chemical
hazards commonly
encountered in the field.
 Explain warning
properties of various
chemical hazards.
 Describe how to evaluate
and control these hazards.

4. • The degree of hazard
associated with a particular
chemical will depend on:
– Its physical properties
– Its toxicity
– The way it is used
– The environment in
which it is encountered.

5. Chemical Handling/Hazards
Chemical forms
Liquids, Solid, Dust, Fume, Mist, Vapour & gas
Modes of Entry
Injection, Skin Absorption/eyes, Inhalation
Toxicity
Ability of the substance to harm the body and
the manner in which it harms the body
Quantity + Duration + Toxicity = Dose
The dose makes the poison

6. Physical Classification
Solids Aerosols
Liquids Vapours
Chemicals may be
found in solid, liquid,
aerosol, or gas and
vapor form.
The degree of danger
varies according to the
form of the chemical
and the factors
previously discussed.

7. Solids
• Not all forms of a chemical pose a health
hazard.
• For example, a lead pipe is not a significant
health hazard.
• However, the lead can become a human
health hazard if the pipe is sanded or welded,
producing lead dust or fumes.
• The dust or fumes can become airborne and
be inhaled, or it can leach into water and be
ingested.

8. Solids
• A chemical may be hazardous even in
solid form.
• For example, individuals who are
sensitized to nickel may develop
dermatitis from skin contact with the
metal.
• Fuming solids emit toxic vapors that
may be inhaled.
• Some materials, such as pesticides, can
evaporate directly from solid form.

9. Aerosols
• Aerosol is a term used to describe fine
particles (solid or liquid) suspended in
air.
• Examples of aerosols include dust,
fumes, mist, fog, smoke, and smog.
• Knowing how various aerosols are
generated will help you anticipate
where aerosol hazards may exist in the
field
• Aerosols may be a hazard to the eyes,
skin, and the respiratory system.

10. Liquids
• Many liquids are hazardous
in contact with the skin. They
either damage the skin or they
are easily absorbed through
the skin.
• chemicals that can damage or
be absorbed through the skin
and will have this effect on all
skin, not just the hands.

11. Liquids
For example,
• inhalation is the primary route for a
chemical to enter the body. Its vapor
pressure is important in determining the
liquid’s degree of hazard.
• Liquids with a low vapor pressure may
create a low airborne concentration.
• Liquids with a high vapor pressure may
produce high airborne concentrations.
• The hazard level of an airborne
concentration depends in part on the
chemical's toxicity.

12. Health Hazards
1. Irritant
2. Toxic Effect
3. Asphyxiant
4. Teratogenic (unborn child)
5. Mutagenic (Heritable genetic defects)
6. Oil Acne (Cutting Oil)
7. Particle size (Micron) ≤10 ≤100
8. Photosensitiser (Irritant or Sensitizer + UV)
Coal Tar Pitch.

13. Exposure Route
Lung
Ear Eye
Nose
Mouth
Musculo-
skeletal
Skin
Whole body

14. Target Organs
Lung Heart
Digestive tractLiver
Kidneys
Ear
Eye
Skin
Nose
Mouth
Reproductive
system
CNS
Central Nervous System

15. Personal Protective Equipment
1. Depends;- Physical Form, (Solid, Gas, Liquid)
2. Potential health effects (Irritancy - Toxicity)
3. Quality handled
4. Method used
5. Hazard Labelling
6. Break Through Period
Types = Protective Clothing, Gloves, Goggles,
Shields
Hearing Protection, Respirator -
Air Supplied
Air Purified

16. Control Measures
•Elimination
•Substitution
•Changed Method of work
•Engineering Control (extraction)
•Information, Instruction & Training
•Personal Protection Equipment
•Monitoring
•Recovery Measures (Emergency
Plan)

18. National Fire Protection Association
Hazard Classification
0
W
2
4
Flamability
Reactivity
(Stability)
Health
Water