Air Monitoring Plans
Written air monitoring plans should be developed by a competent person for all friable asbestos removal. OHMS Asbestos can assist by determining all air monitoring requirements for a project such as the locations, rate and frequency of sampling. In addition to the required control monitoring, clearance monitoring will also be assessed to ensure sufficient pumps and suitable locations within the work area are monitored. It should be noted that an air monitoring program is not always necessary for non-friable asbestos removal however it is considered best practice and good occupational hygiene.
Considerations for the various types of monitoring should be reviewed and implemented accordingly, as follows:
- Background monitoring - involves testing the location of upcoming asbestos removal work prior to disturbance. This is typically conducted to establish a baseline of ambient fibre levels and to determine if other fibres may be present in the air.
- Exposure monitoring – tests the air in a person’s breathing zone to determine a person’s likely exposure to respirable asbestos fibres. Exposure monitoring is designed to reliably identify a person’s exposure, which also allows for a review to ensure the correct respiratory protection equipment (RPE) is being utilised.
- Control monitoring – is when the air is tested to measure the level of respirable airborne asbestos fibres in the vicinity of an asbestos exclusion zone during asbestos removal or remediation. It allows for the testing of the effectiveness of implemented control measures while works are conducted such as the integrity of enclosures and dust suppression techniques.
- Clearance monitoring – tests the air to measure the level of airborne asbestos fibres in an area following asbestos removal works.
When the level of airborne asbestos fibres is measured as being below 0.01 fibres/ml the asbestos work area is considered as cleared and can return to normal occupation.