Health and safety in the laboratory and field

# 7.5 Control measures

### 7.5.1 Control measures to avoid exposure

There are four main methods of exposure to chemicals:

1. Inhalation – This is the main method of exposure to volatile solvents and gases.

2. Skin absorption – Certain chemicals possess the ability to penetrate through pores of skin (for example, mercury compounds and hydrofluoric acid).

3. Splashes to the eye – The eye is one the most sensitive organs, and splashes of chemicals can cause severe pain and, in extreme, cases blindness.

4. Ingestion – Residues of chemicals can be left on your hand and then be transferred to the food that you eat. This is why it is important to wash your hands after carrying out laboratory work.

There are a number of ways to reduce or eliminate exposure to chemicals. The most common method utilised is a fume cupboard (also called local exhaust ventilation, LEV).

Some chemicals have adverse reactions when exposed to air or moist air; these have to be handled under an inert atmosphere, usually oxygen-free nitrogen or argon. For highly toxic or unstable chemicals these may require a dry box or negatively pressurised containment.

OpenLearn - Health and safety in the laboratory and field
Except for third party materials and otherwise, this content is made available under a Creative Commons Attribution-NonCommercial-ShareAlike 4.0 Licence, full copyright detail can be found in the acknowledgements section. Please see full copyright statement for details.