Laboratory Hazards and First AidCHAPTER 1

Broken glassware

Corrosive reagents

Mechanical hazards

Poisonous fumes that could be inhaled

Inflammable chemicals

Gas leakages

Electrical hazards.

Laboratory coat has to be worn in order to protect oneself from corrosive splashes

One has to be careful while handling gases4

Blood, urine, cerebrospinal fluid (CSF) and other biological fluids should be handled with great care as they are potential sources of infections like human immunodeficiency virus (HIV) and hepatitis

Chemical work involving irritating chemicals and dangerous infectious materials should always be conducted under hoods with good exhaust and adequate ventilation

Safety cabinets and hoods should be used while handling corrosive reagents5

Electrical heater and other electrical appliances should be checked and insulated frequently. Damage should be rectified immediately

Bunsen burner should never be used around inflammable material like ether, and acetone

General health should be maintained at all costs as an effective means for keeping natural immunity and resistance

Eating and drinking in the laboratory must be avoided.

Exercise great care and take precautions while mouth pipetting. The mouth of the pipette should be plugged with cotton or piece of rubber while filling

One should not be engaged in conversation or other disturbances

Automatic dispensers and automatic pipettes must be used for pipetting acids, alkalis, corrosive solutions and poisonous solutions

The hands should be kept free of cuts and abrasion

Hands should be washed with soap water followed by washing with disinfectant material

Pipettes and other instruments employed should be placed immediately in disinfectant solution.

Open flames should not be left unattended

Any leakage of gas should be properly attended and reported

Smoking should be strictly prohibited

Burning matchsticks should not be thrown in waste baskets.6

Sand or blanket should be used to put off the small fire

For longer blazes, “Fire Extinguishers” have to be used

Water should not be used on electrical fire

Water should not be used on a fire caused by organic solvents such as ether, alcohol, petrol, etc.

While trying to escape from fire, in case if it cannot be extinguished quickly, it is safe to stay close to the floor and crawl by covering mouth with damp cloth.

Spit the corrosive solution

Promptly rinse the mouth

Antidotes such as 8% magnesium hydroxide (milk of magnesia) or egg white mixed in water can be used orally to neutralize the acid

Seek medical help immediately.

Promptly rinse the mouth

Antidotes such as lemon juice or 5% acetic acid can be taken orally to neutralize the alkali

Seek medical help immediately.

First wash with lots of water and then wash with 5% sodium carbonate or 5% ammonium hydroxide

Seek medical help immediately.7

Wash immediately with lots of water and later with 5% boric acid or dilute acetic acid solution

Seek medical help immediately.

Cotton wool and gauze

Roller bandage

Scissors

Acetic acid

Milk of magnesia

Spirit

Adhesive tapes

Disinfectant solution

About 5% sodium carbonate.

All chemicals should be considered as potentially dangerous and should be handled carefully. One should be aware that accidental injuries can occur either from direct contact through skin, by inhaling vapors, powder or swallowing by mistake while pipetting

Clear labeling of all the bottles containing chemicals and reagents should be done and their potential hazards should be noted on the label

Reagent bottles should be held with both hands and should not be carried by holding their necks

The reagent bottles in use should be kept on shelf at the eyelevel of the user8

Corrosive chemicals should be opened with great care and added slowly to water with continuous cooling and stirring as these substances can destroy the living tissue, e.g. Strong acids like sulfuric acid, hydrochloric acid and strong alkalies like potassium hydroxide, sodium hydroxide, etc.

Automatic dispensers should be used to dispense acids, alkalies and corrosive liquids

Toxic chemicals such as cyanides, barbiturates must be kept locked in cupboards and mouth pipetting of these should be avoided at any cost

Some organic solvents are highly toxic to certain organs, e.g. Benzene is toxic to bone marrow; carbon tetrachloride and halogenated hydrocarbons are toxic to liver, etc. Hence, their use should be minimized in assays

Precautions must be taken while handling carcinogenic substances such as benzidine, orthotolidine. Bottles containing such substances have to be labeled as carcinogenic. Skin contact with them must be strictly avoided and rubber or plastic gloves should be used while handling these substances

One has to be careful while handling explosive substances. Certain precautionary measures must be followed like:

• Perchloric acid should be kept in fume cupboard
• Picric acid should be stored in a container of water tightly closed with cork or rubber stopper
• Ether should be kept in brown or dark bottles away from sunlight since on exposure to sunlight they form peroxides, that when raised to certain sufficient concentration cause violent explosion
• Cylinder containing inflammable gases like hydrogen, propane, acetylene should be kept outside the laboratory when not in use.9

One should not be panic

Alarm should be raised as soon as possible

The laboratory should be evacuated, to minimize further damage to property

Gas and electricity connections have to be turned off immediately

In case of fire attacks, fire extinguishers should be used to tackle them

In case of large fires, the fire brigade has to be called.

Neutralization of acids and alkalies should be done prior to their washing in the sink

Organic solvents should be stored in metal drums and later it must be washed off

Some chemicals can be cleared or disposed by incineration.