Hazard Communication - HAZARD EVALUATION
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Chemicals present two types of hazards, physical hazards and health hazards.
Physical Hazards
Physical hazards are explosion, fire, and combustion. Chemicals can be sources of stored energy and capable of causing physical damage to property. Petrochemical products and compressed gas cylinders are examples of chemical products containing stored energy. Stored energy can cause physical damage to buildings, rooms, automobiles, and other physical objects if it is released improperly or accidentally. Other chemicals may be classified physical hazards because they possess the ability to support combustion of materials in their presence even though the chemical itself may not be flammable.
Health Hazards
A Chemical Health Hazard is the ability of a chemical to cause ill effects upon a person's health and well-being as a result of overexposure for example, chemical overexposure can cause a wide variety of adverse reactions in individuals from negligible to lethal. In order to increase understanding Occupational Health Specialists have divided health hazards into two major categories, Acute Health Hazards and Chronic Health Hazards. The difference in these two terms is the amount of time required for the symptoms of chemical overexposure to occur.
Acute Health Hazards are categorized as causing immediate symptoms to chemical overexposure For example, car battery acid is an acute health hazard. Automobile batteries primarily contain a Sulfuric Acid and distilled water. If you accidentally splashed some of this solution onto your skin the sulfuric acid would cause an almost immediate itching and burning sensation. Most people would wash the affected area to stop the discomfort and irritation. Battery acid is an Acute Health Hazard because the ill effects of overexposure (the itching and burning sensation) occur immediately.
Chronic Health Hazards are categorized as causing delayed or gradual over time symptoms to chemical overexposure. Chemicals classified as "chronic health hazards" can cause ill health effects without your immediate knowledge, the symptoms may not appear until months or years later. For example, spent motor oil presents a "chronic health hazard." It's known that repeated skin contact to used motor oil can cause cancer. A person would not have any indication of this hazard at the time the oil got on their hands. The cancer most likely would not occur until much later and after repetitive exposures. Chemicals classified as chronic health hazards clearly present more risk to users and therefore require special handling procedures (gloves and mandatory washing in this example).