Charandry

Chemical Hazards & communication

Forms of chemical agent a) Dusts

- Solid particles suspended in air; fine & coarse

- Created by pulverizing, construction, furnace ash removal etc.

- Inhalable & Respirable Dust

b) Gases

- Substances above their boiling point

- Gets absorbed into blood when inhaled

c) Vapours

- Substances at or very close to boiling points

- Enters blood stream when inhaled

d) Liquids

- Substances at a temperature between freezing and boiling points

- Routes of entries are ingestion & absorption

e) Mists

- Similar to vapours but closer to liquid phase

- Produced by spraying

- Inhalation, ingestion, absorption

f) Fume

- Collection of very small condensed metallic particles of size < 1µm

- Generated by welding process

- Fall in the respirable range

g) Solids - Absorption or ingestion

Chemicals can change their physical form

Classification of hazardous substances

1. Health Hazard

Substance may be a carcinogen, can

damage eyes, lungs, or other target

organs; can also be a sensitizer,

mutagen, or be a respiratory

sensitizer.

E.g. Asbestos, tobacco smoke

Definition. A sensitizer & Mutagen

A sensitizer is defined by OSHA as "a chemical that causes a substantial proportion of exposed people or animals to develop an allergic reaction in normal tissue after repeated exposure to the chemical." The condition of being sensitized to a chemical is called chemical hypersensitivity

Mutagen is a physical or chemical agent that changes the genetic material, usually DNA, of an organism and thus increases the frequency of mutations above the natural background level.

2. Acute Toxicity

The adverse effects of a

substance that result either

from a single exposure or

from multiple exposures

in a short space of time.

May be fatal or toxic.

3. Aquatic Toxicity

The effects of manufactured

chemicals and natural

materials and activities

on aquatic organisms

4. Oxidizing Agent

Strong oxidizers are capable

of forming explosive mixtures

when mixed with

E.g. Benzene

Explosive articles, and

substances as well as mixtures

and articles that are manufactured

to produce a practical explosive

or pyrotechnic

E.g. – Isocyanates, latex, wood dust

5. Explosives

6. Corrosive

Causes Skin Corrosion or Burns,

can cause eye damage and

Corrosive to metals.

Including compressed gasses,

liquefied gasses.

Gas released may be very cold.

Gas container may explode

if heated.

7. Gasses Under Pressure

8.Flammables

Flammable gasses, liquids,

or aerosols; self-reactive or

pyrophoric material;

self-heating substances and

mixtures, organic peroxides.

9. Irritant

Harmful to the skin or eyes,

a skin sensitizer or respiratory

irritant, may experience narcotic

effects