A more complex severity rating scale has been proposed by Holt and Andrews (1993)
as follows:
Catastrophic i.e. imminent danger exists, hazard capable of causing death, illness on a wide scale.
Critical hazards that can result in serious illness, severe injury, property and equipment damage.
Marginal i.e. hazards that can cause illness, injury or equipment damage, but the results would not be expected to be serious.
Negligible i.e. hazards will not result in serious injury or illness; remote possibility of damage beyond minor first aid case