Gas monitoring instruments are designed to protect personnel from unseen hazards that may exist in workplace environments, including confined spaces. It is vital to worker safety that these instruments are maintained and calibrated properly.
Thousands of products are available which contain gases and mixture of gases stored under pressure in cylinders. Most of these gases are classified as compressed gases.
For years employees have experienced health related side effects or injury from exposure to substances in the work place. The coal miners would have canaries in cages to alert them of poisonous gas pockets. This didn't work too well, but it was all they had. Workers entering confined spaces such as holding tanks or manholes for utility services would be overcome by toxic gas or oxygen defiance and ultimately die.
Various governmental agencies have been established to ensure workers can perform jobs without being exposed to hazardous levels of substances.