Manufacturer: Carrier Corporation (Syracuse, New York) Product Category: HVAC Equipment / Air Distribution

Product Description

Carrier Corporation was one of the two or three dominant American manufacturers of commercial and industrial HVAC equipment throughout most of the twentieth century. Beyond its familiar chillers and air-handling units, Carrier and its distributor network allegedly supplied the accessory materials used to insulate, lag, and finish ductwork on the field side of the installation. According to allegations in publicly filed asbestos personal-injury and wrongful-death litigation, one of these accessory products was an asbestos-fabric ductwork lagging system — consisting of woven asbestos cloth (typically chrysotile) applied as an outer jacket over ductwork insulation, sealed and finished with asbestos-loaded lagging cement troweled to a smooth exterior.

Asbestos-fabric lagging was allegedly used extensively on rectangular and round supply and return ductwork downstream of Carrier air-handling units where thermal performance, condensation control, and a durable paintable finish were required — commonly in hospitals, schools, high-rise commercial buildings, industrial plants, and Navy shore-facility mechanical rooms. Documented asbestos-use period, according to publicly filed litigation records: approximately 1930s through 1975.

Workers Exposed

Insulators were the primary trade allegedly exposed to Carrier’s asbestos-fabric ductwork lagging. Publicly filed litigation records allege that insulators unrolled woven asbestos cloth, cut it to length with shears, wrapped and pinned it around block or blanket duct insulation, and then troweled asbestos lagging cement over the fabric to seal the joints and produce the finished exterior. Mixing dry lagging cement — supplied in paper sacks — with water generated visible dust clouds in the mechanical room.

Sheet metal workers installing the underlying ductwork worked alongside insulation crews and were allegedly exposed to airborne chrysotile released during adjacent lagging operations, as well as during cut-in of new dampers and access doors through previously lagged duct runs.

HVAC installers performing final connections at Carrier air-handler discharge plenums allegedly encountered fresh lagging installations and had to re-cut lagging around field-fitted transitions.

Pipefitters and steamfitters sharing mechanical rooms with lagging crews were bystander-exposed to airborne fiber generated by fabric cutting and cement mixing.

Demolition and renovation workers decades later allegedly disturbed aged, deteriorated asbestos fabric lagging during HVAC replacement and building renovation, releasing chrysotile fiber from the degraded cloth and finish coat.