Workers may be exposed to a variety of airborne substances such as dusts, fumes, gases, vapours, mists and smoke. It’s important to keep concentrations of all airborne contaminants as low as possible, regardless of if they are known to present a health hazard.
Cleaning up dusts can actually worsen the problem through spreading elsewhere: this is known as re-suspension. Through cleaning the dust, you create the risk of smaller particles being transported from the initial exposure/emission point to another through air, wind or on clothing.
Dusts and fumes can also accumulate or remain suspended in the air long after their production has ceased.
A person conducting a business or undertaking (PCBU) is responsible for ensuring that workers are not exposed to contaminants above the workplace exposure standards. This standard relates to a particular chemical or substance within a worker's breathing zone that could cause dangerous health effects or undue discomfort. The legal concentration limits for a particular chemical or substance must be adhered to.
You should consider monitoring contaminant levels for chemicals with exposure standards:
- if there is uncertainty about whether the exposure standard has been or may be exceeded, or
- to determine whether there is a health risk.
Using monitoring equipment, an atmosphere is considered dangerous if the results indicate:
- an unsafe oxygen level, which is common to grain silos and waste pits
- a concentration of oxygen resulting in increased risk of fire
- a concentration of flammable gas, vapour, a mist of fumes exceeding 5% or the lower explosive limit
- a presence of combustible dust, such as wood dust, bio-solids, sugar, starch, flour, feed or grain in a quantity and form that would result in a hazardous area. Dust explosions usually occur when combustible dust or fibre from paper, grain, organic compounds and meals accumulates, is disturbed and released into the air, and ultimately comes into contact with an ignition source.
Records of air monitoring for airborne contaminants must be kept for a minimum of 30 years, and are required to be available to workers who are exposed.
To maintain a safe working environment for everyone, follow these safety solutions:
- regularly inspect and clean ventilation and dust collection systems to remove dust build-up
- isolate the hazard by either enclosing processes or using a remote operation, such as pendant controls, enclosed vehicle cabs and control rooms
- install local exhaust ventilation to capture dust and fumes at the source
- provide personal protective equipment (PPE) that is:
- suitable for the nature of the work and the hazard, such as gloves, masks, goggles, face shields and respirators
- comfortable to wear, and of a suitable size and fit
- maintained, repaired or replaced when required
- used or worn by workers who have been trained in its use and care
- adopt good workplace hygiene practices, like having a regular cleaning routine where you vacuum or wet mop the floors instead of sweeping them
- consider your lunch rooms and/or non-work areas as clean zones, where contaminated PPE must be removed before entering.
The following information is available from Safe Work Australia.
- Workplace exposure standards for airborne contaminants - lists exposure standards and contains key information about the way they are applied, while being interpreted under work health and safety laws.
- Guidance on the interpretation of workplace exposure standards for airborne contaminants - provides help with interpreting exposure standards.
- Hazardous chemicals
Evaluation of exposure standards
Safe Work Australia is inviting comment on their review of the Workplace Exposure Standards for airborne contaminants. Draft evaluation reports and recommendations for each chemical will be made available for public comment throughout 2019-2020.
These Australian standards provide further information on respiratory protection and are available for loan, free of charge, from our Library.
- AS/NZS1715: Selection, use and maintenance of respiratory protective equipment
- AS/NZS1716: Respiratory protective devices