by 
► Hazard: It is defined as “ any event with the potential to cause harm, ill health, injury, damage to property, plants, products or the environment, production losses or increased liabilities.”
► Risk: It is combination of probability of occurrence and its severity of consequence.
R= P X S
► Nearmiss: It means any unplanned, sudden event that could have caused injury to man, materials or environment or could have involved a loss of containment possibly giving rise to adverse effect but not resulted in such accident.
► Accident: It is an undesired or unintentional event that results in physical harm to a person or damage to property or environment. It is usually the result of a contact with a source of energy.
► Unsafe condition: It means existence of a mechanical, physical, chemical or environmental condition, situation or state of affairs, which may cause hazard or accident.
► Unsafe act: It means an act which a prudent (Careful) man should not have done and which results in hazard, accident or injury.
