Document ID: chunk:federal_register_of_legislation:F2016L00420:front:0:p31
Version: federal_register_of_legislation:F2016L00420
Segment Type: other
Provision Reference: 
Character Range: 82380–85338

necessary.

Exhaust gases and air should be discharged where it will not cause other hazards. For example, fume cupboard extraction systems should not exhaust close to air intakes and should be in compliance with any local building or environment protection requirements. Exhaust systems can also be fitted with means to reduce airborne contaminants which may be harmful to the environment or people prior to discharge to the atmosphere. This might include particulate filters, absorbents and adsorbents (e.g. carbon), catalysts, scrubbers or burners.

Regular checks of these systems should be included in planned maintenance schedules to ensure that vents remain unobstructed.

Mechanical ventilation
Inlet and outlet vents located on opposite sides of the storage area at low levels provide airflow across the floor. Where both inlet and exhaust are mechanically assisted, capacities and rates should be adjusted to ensure that the pressure inside the store or room never exceeds that outside and airflow into any adjoining work areas and offices is prevented.

Local exhaust ventilation
Local exhaust ventilation is used to remove airborne contaminants before they reach the breathing zone of workers in the area.  It is used for effective control of more highly toxic contaminants created in large quantities and is applied close to the source of generation. It is more effective than increasing general ventilation to try to dilute toxic contaminants.

Natural ventilation
Natural ventilation can be used to control small amounts of relatively low toxicity contaminants including dusts, fumes, gases and vapours which have low and steady rates of generation.
It requires a large building space for dilution and relatively large air flow through open doors, windows or ceiling exits. For solvent storage areas, where heavier than air vapours may accumulate in lower regions (e.g. near floor level) with a subsequent build-up of hazardous concentrations, vents should be provided at a level immediately above any spill containment, on the opposite sides of a room or space, to provide for airflow across the storage or handling area. High level ventilation may be necessary for temperature control (e.g. roof vents to allow the escape of warm air).
Note: Vents in a screen wall may negate any fire protection or vapour barriers.
To ensure the effectiveness of ventilation systems, these should be designed in accordance with appropriate technical standards, and installed and maintained by qualified or experienced persons, such as engineers or occupational hygienists.
Further information on the design of ventilation systems can be found in:
    * AS 1940: The storage and handling of flammable and combustible liquids
    * AS/NZS 60079.10.1: Explosive atmospheres – Classification of areas – Explosive gas atmospheres [IEC 60079-10-1, Ed 1.0 MOD]
    * HSG258 Controlling airborne contaminants at work: A guide to local exhaust ventilation (LEV); 2nd