Australian Capital Territory Current Regulations Australian Capital Territory Current Regulations(1) A person conducting a business or undertaking at a workplace must manage risks to health and safety associated with a hazardous atmosphere at the workplace, in accordance with part 3.1 (Managing risks to health and safety).
(2) An atmosphere is a hazardous atmosphere if—
(a) the atmosphere does not have a safe oxygen level; or
(b) the concentration of oxygen in the atmosphere increases the fire risk; or
(c) the concentration of flammable gas, vapour, mist or fumes exceeds 5% of the LEL for the gas, vapour, mist or fumes; or
(d) combustible dust is present in a quantity and form that would result in a hazardous area.