ABC of Safety in the Biological Sciences




Bleach, liquid pool chlorine.
Avoid skin and eye contact.
Avoid inhalation or ingestion.
Keep away from heat.
Keep away from light.
Keep away from metal surfaces.
Keep away from oxidising or reducing agents.
Wash hands thoroughly after handling.
Faintly yellow liquid with slight chlorine odour.
Sodium hypochlorite is a strongly corrosive substance. Skin contact results in burns unless the liquid is removed quickly. It can act as a sensitiser. Eye contact results in burns and damage may be permanent. Inhalation will cause coughing and respiratory difficulties. Ingestion will cause severe local burns to the mouth, oesophagus and stomach.
Skin ­ immediately remove contaminated clothing and wash the affected area with soap or mild detergent and large amounts of water until all evidence of the chemical has been removed (approximately 15 minutes). Burns will need medical treatment. Wash contaminated clothing before re­use.
Eyes ­ immediately wash the affected eye with large amounts of water until all evidence of the chemical has been removed (approximately 15 minutes). If irritation or pain persist seek immediate medical attention. Burns will require immediate medical attention.
Inhalation ­ remove from the area of exposure to fresh air. If breathing has ceased apply artificial respiration. Keep warm and allow to rest. If irritation persists or develops seek medical attention.
Ingestion ­ wash out the mouth thoroughly with water and give water or milk to drink. Do not induce vomiting. Seek immediate medical advice.
Heating produces toxic fumes of chlorine. Incompatible with acids, strong oxidising and reducing agents, metals and metallic salts.
Store in a cool, dry atmosphere in the dark away from heat and incompatible substances.
Use a fume hood to minimise exposure to this substance. Wear protective clothing. A long sleeved laboratory coat or gown, rubber gloves, safety goggles and a face mask as a minimum standard.
Rubber gloves, face shield and laboratory coat. A body shield should be available for the more active agents. Replace the face shield with self contained breathing apparatus for such agents as chlorine and bromine.
Gas leak: if the valve is leaking because it cannot be closed, the gas can be bubbled through a reducer (sodium sulphite) and excess sodium bicarbonate solution. Be sure to include a trap in the line to prevent the solution being sucked back into the cylinder. If this cannot be done the cylinder should be placed in or adjacent to a fume hood and left to bleed off. If the leak is in the valve assembly, a plastic bag can be fastened over the head of the cylinder which can then be taken outside or to a fume hood.
Liquid or solid: cover with a reducer (sodium thiosulphate, a bisulphite or a ferrous salt not carbon, sulphur or strong reducing agent). Mix well and spray with water. A sulphite or a ferrous salt will require addition of 3mol/l sulphuric acid to promote a rapid reduction. Scoop the slurry into a container of water and neutralise with soda ash. Discharge to sewer with a large excess of water. Wash the site thoroughly with a soap solution containing some reducer.
Add to a large volume of concentrated solution of reducer (sodium thiosulphate, a bisulphite or a ferrous salt and acidify with 3mol/l sulphuric acid). When the reduction is completed add soda ash or dilute hydrochloric acid to neutralise the solution. Discharge to sewer with a large excess of water.


BACK to the top of the Glossary Contents List
BACK to the top of the Chemical Contents List