Although manufacturers have long since abandoned using asbestos products as insulation, the material was once widely used as insulation for heating and air conditioning systems. Because asbestos is most dangerous when airborne, these outmoded air-conditioning systems pose a significant public health hazard. By and large, campaigns to identify and replace air conditioning systems using this toxic material have been successful. However, many systems still remain, often unbeknownst to their owners.
Identifying risk
Asbestos was widely used as a building material until the late 1990s. If your home or building was constructed prior to 2004 and has not yet been properly inspected, we recommend hiring an assessor to determine if your building is at risk.
Air-conditioning units with asbestos insulations
What to look for
Friable asbestos insulation on air-conditioning ducts often comes in four different forms:
- As a paper-like sheath, usually containing 20-60 percent asbestos fibers.
- Asbestos rope inside heater bank
- As a chalky plaster, similar in appearance and texture to that of a cast for a broken arm.
- As a tape, usually found around metal piping and ducts. This friable tape cannot be abated, making replacement of the entire duct necessary.
- Asbestos millboard insulation inside the ductwork around heater banks.
Asbestos millboard insulation material inside the heater banks of air conditioning units
This is a graphic of a heater within the duct work of an air-conditioning system. The duct is lines with asbestos millboard.
When the air flows over the millboard, there is a high likelihood of asbestos fiber release. As such you can be breathing in asbestos fibers while at work.
| Asbestos millboard insulation material around the heater banks of air conditioning units |
Do I remove it?
- Is the asbestos inside the air conditioning system? If yes then urgent removal is essential.
- Is the asbestos insulation damaged? If yes, we recommend removing the materials immediately.
- Is your property commercial or residential? Removal becomes a much more pressing issue in a residence than in a non-living area. While damaged or friable materials should be removed regardless of the type of building, non-living areas are generally not considered an emergency.
- Can you abate it? Asbestos removal is not always necessary. However, if it is in the duct work of the air conditioning system, then urgent removal is essential. Sometimes abating the material if not in the duct work – sealing it in a casing that will prevent its release into air – is not only the more cost effective option, but the safer one.
When considering the presence and state of any asbestos in your air conditioning or heating systems, we recommend employing professionals for assessment, abatement, or outright removal. With a material as dangerous as asbestos, safety is always the best policy. Asbestos and air conditioning don’t mix.
| Different types of Air conditioning Systems containing asbestos insulation materials | ||
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| Asbestos inside an air conditioning heater bank | Asbestos inside an air conditioning heater bank 2 | Asbestos inside an air conditioning heater bank 3 |
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| Asbestos inside an air conditioning heater bank 4 | Asbestos inside an air conditioning heater bank 5 | Asbestos inside an air conditioning heater bank 6 |
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| Asbestos inside an air conditioning heater bank 7 | Air conditioning unit with asbestos insulation | Air conditioning duct |
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| Asbestos contain heater bank | Asbestos containing heater bank | Asbestos inside duct |
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| Asbestos insulation to discarded air con duct work | Asbestos insulation inside heater to floor unit | Asbestos millboard to heater banks |
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| Asbestos to heater banks 1 | Asbestos to heater banks 2 | Asbestos to heater banks 3 |
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| Asbestos to heater banks | Asbestos to heater banks – 3 | Asbestos to heater banks – 2 |
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| Freestanding air conditioning unit with asbestos to internal heater bank | Heater bank concealed in ceiling | Heater Bank under the duct |
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| Heater Bank to air conditioning Ductwork – contain asbestos insulation | Heater Bank to air conditioning Ductwork – contains asbestos millboard lining | Large asbestos insulated Heater Bank |
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| Millboard Insulation | Removing an asbestos heater bank | Roof top air conditioning unit with asbestos heater bank 3 |
