extinguisher

Flammable liquids

and gases, electrical fire

—

Dry powder As above —

Foam Flammable liquids —

Halon spray All kinds of fires —

8 Concise Book of Medical Laboratory Technology: Methods and Interpretations ¾ Biological safety cabinets: Prevent dangers arising out

of aerosols and splatters

¾ Splatter shields: Provide protection from splatter of

specimen and chemicals

¾ Pipetting aids (teat or electromechanical devices).

Prevent from hazards arising out of mouth pipetting

¾ Goggles: Protect eyes from impacts and splashes

¾ Face shields: Protect the face from impacts and

splashes.

Safety with Chemicals/Reagents

Excepting just a couple of reagents, almost all chemicals/

reagents used even in the most basic laboratory are lethal

poisons if consumed by anyone. Even if they are splashed

on the skin/eye, they can cause irreversible damage. There

is an appropriate way of handling and storage of hazardous

chemicals to avoid injury and damage to self and others.

In our country (and other tropical nations), excessive heat

can decompose many chemicals, cause explosions, or lead

to the formation of toxic fumes.

Labeling of Hazardous Reagents/Chemicals

At appropriate places, display the prohibition signs; and

on all dangerous reagents or chemicals, stick Hazard

warning symbols. In the following pages, important signs

and symbols as related to safety in the laboratory are given.

Incompatible Chemicals

Fair number of common laboratory chemicals react

dangerously if they come in contact with specific chemicals.

Ensure that you keep such chemicals away from each other.

A few examples are listed below:

Acids

¾ Acetic acid with chromic acid, nitric acid, hydroxyl

compounds, ethylene glycol, peroxides and permanganates

¾ Chromic acid—with acetic acid, alcohol, glycerol and

other flammable liquids

¾ Sulfuric acid—with chlorates, perchlorates, permanganates and water.

Vaporizing Substances

¾ Acetone—with sulfuric acid and nitric acid

¾ Flammable liquids—with chromic acid, hydrogen

peroxide, nitric acid, ammonium nitrate and halogens.

Others

¾ Alkali metals, e.g. calcium, potassium, sodium (these

form hydroxides on coming in contact with water) and

with other chlorinated hydrocarbons

¾ Chlorine—with ammonia, hydrogen, benzene and

other finely divided metals

¾ Copper—with azides, hydrogen peroxide and acetylene

¾ Cyanides—with all acids and alkalies

¾ Hydrogen peroxide—with copper, iron, chromium and

most other metals

¾ Iodine—with acetylene and ammonia

¾ Sodium azide—with lead, copper and other metals.

Flammable Chemicals

These include ether, xylene, toluene, methanol, ethanol,

glacial acetic acid, acetic acid, acetone, acetic anhydride,

alcoholic Romanowsky stains and acid alcohol, etc.

Storage

These should be stored in a fire-proof metal box at ground

level, preferably in a cool store. A container well lined with

tin foil can also be used. Store only small quantities of such

solvents on the shelves.

Safe Use

Ensure that there is no open flame nearby while opening a

bottle containing flammable solvent. Nearest flame should

be at least 10 feet away. Never heat a flammable liquid over