Asbestos Blanket

Asbestos blanket is a flexible, woven or felted insulation material consisting predominantly of asbestos fibres, typically chrysotile or amosite. Manufactured as sheets or rolls of varying thickness (from a few millimetres to over 25 mm), asbestos blankets were designed to wrap around boilers, steam pipes, heat exchangers, turbines, and other high-temperature industrial equipment.

The product was widely used from the 1930s through the late 1970s, particularly in power stations, oil refineries, chemical plants, naval vessels, and commercial heating systems. Asbestos blankets provided excellent thermal insulation, were flexible enough to conform to irregular shapes, and offered inherent fire resistance. Some formulations incorporated wire mesh reinforcement for added structural integrity.

Asbestos blanket is classified as a high-risk friable material (Risk Level 5). The woven or felted structure means that fibres are loosely bound and readily released when the material is handled, folded, cut, or disturbed in any way. Ageing, vibration from machinery, and thermal cycling further degrade the material, causing it to become dry and brittle. In this state, even minor contact generates clouds of airborne asbestos fibres.

The health risks from asbestos blanket exposure are severe. Workers who installed, maintained, or removed these blankets without proper protection — particularly laggers and power station workers — suffered disproportionately high rates of mesothelioma and asbestosis. The latency period for these diseases can exceed 40 years.

Removal of asbestos blankets requires a licensed asbestos removal contractor operating under full containment conditions with negative air pressure, HEPA-filtered air scrubbers, and personal protective equipment including powered air-purifying respirators. Air monitoring must be conducted throughout the removal process and during the clearance phase to confirm fibre levels are below the control limit before reoccupation.