51Managing risks to health and safety

51  Managing risks to health and safety  (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.  (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.