The Nature of Chemical Hazards

The term hazard may be broadly defined as “anything that has a potential to cause damage to human health, property and environment”. Hazards in a research laboratory may be of various forms: mechanical, electrical, and chemical. Examples include: noise, rotating equipments, compressed gas cylinders, electricity, high temperature / high pressure equipments, chemicals that are toxic / flammable / corrosive / radioactive, etc [Ref. 1]. Of these by far the most common and dominant hazard is the possible exposure to a variety chemicals that are implicated today in research in various fields of science and engineering. Many of these chemicals, especially if not properly used, may endanger health and safety, and pollute the environment, often irreversibly. Thus, a systematic assessment of the nature of personnel, property and environmental hazard posed by a chemical employed in the laboratory is necessary as part of a Department’s HSE goal.

The following material attributes contribute to toxic heath-hazard due to possible acute, repeated or prolonged exposure [Ref. 2]:

  • toxic to human specific human organs (kidney, liver, lung, etc)
  • toxic to human physiological systems (reproductive, nervous, blood, etc)
  • corrosive (strong acids, bases, dehydrating agents, oxidizing agents)
  • irritant (non-corrosive chemicals that cause reversible inflammatory effects on human tissue)
  • cancer causing
  • sensitizing (allergenic)
  • radioactive

    Fire and explosion hazards may be classified as follows:
     
  • explosive
  • oxidizing
  • extremely flammable
  • highly flammable
  • flammable

    The following properties present hazard to the environment:
     
  • toxic to living organisms
  • persistent in the environment (bio-persistent)
  • bio-accumulative

Also, substances and preparations that cannot be classified by using the above system may be regarded as dangerous if they have properties which are hazardous to human health, to other living organisms or if they can damage property / environment.