CHEMICAL HAZARDS : Chemicals are present in all laboratories. It is good to consider all chemicals toxic and flammable unless one has definite information regarding its nature. Our body also contains number of chemicals but these are very delicately controlled in terms of their nature, amount and action. Every chemical whether required in the body or not becomes harmful at a certain concentration in the body. Ideally speaking no chemical can be considered totally safe or hazard free. The nature and extent of hazard varies and more so the long time effects of many chemicals are not known. One is advised to exercise caution in handling all chemicals and minimise exposure to them.

In a laboratory, human contact with chemicals can take place in three possible ways. These are:

1.  direct contact from spills or by improper handling

2.  inhalation of the vapours, fumes or dust

3.  ingestion i.e. the oral route

Besides these, sometimes we can get affected indirectly also. For example, in case of an explosion one may get physically hurt - may be a fracture. On the other hand highly flammable liquids may catch fire and cause severe bums.