Heating, ventilation and air conditioning (HVAC) systems were often sealed with asbestos ductwork connectors. These connectors consisted of asbestos tape, paper and other materials. Workers who installed, replaced or repaired asbestos ductwork connectors risked exposure. Some have developed asbestos illnesses, including mesothelioma.

01. Asbestos Use in Ductwork Connectors

Why Was Asbestos Used in Ductwork Connectors?

Asbestos was a common additive to many products used in ductwork and HVAC systems, including ductwork connectors. The components of HVAC systems needed to be heat resistant and durable to keep the system operating smoothly.

Metal air ducts throughout homes and buildings connect rooms to the HVAC system. Air then passes through the ducts to provide warm or cool air throughout the rooms.

Ductwork connectors absorb vibrations and noise caused by the airflow through ducting. These connectors needed to resist heat and be strong enough to keep the metal ducts secure. As a result, asbestos was often used in these connectors because of its fire resistance and durability.

Heating ducts and machinery were commonly connected and/or sealed with asbestos tape, fabric or paper. Research suggests asbestos tape used as a sealant or wrap around the ductwork could contain 15% or more chrysotile asbestos.

A hazardous material and environmental testing company inspected white fibrous tape around a home’s HVAC ducts. The house was originally constructed in 1927. Analysis of the duct tape showed it contained 90% chrysotile asbestos.

Asbestos Ductwork Connectors History at a Glance

  • Other Names: Flexible duct connectors, tape duct connector, fabric duct connector, paper duct insulation, duct adhesive, duct sealer, duct wrap
  • Years of Manufacture: 1930s – 1980s
  • Places Used: Heating, ventilation and air conditioning (HVAC) systems
  • Asbestos Use Banned: No
  • Noteworthy Brands: Duro Dyne Corporation, Celotex Corporation, H.B. Fuller, Johns-Manville

Until the 1980s, many HVAC system components contained asbestos. This includes ductwork connectors, duct insulation, vibration dampeners, pipes, pipe insulation and more. As a result, many older homes, buildings and schools may have HVAC systems constructed with asbestos parts.

Exposure to these asbestos-containing materials can lead to health risks. Asbestos exposure causes mesothelioma, asbestosis and other diseases.

02. List of Asbestos Ductwork Connectors

List of Asbestos Ductwork Connectors

Ductwork connectors and other HVAC system components often contained asbestos until the 1980s. The mineral was flexible enough to be woven into fabric or used in tape to seal the ducts. At the same time, asbestos provided durability and heat resistance.

A variety of flexible asbestos duct connectors and sealers were available starting in at least the 1930s. For example, Duro Dyne Corporation produced the following asbestos-containing ductwork connectors:

  • Duro Dyne Duct Sealer
  • Duro-Metal-Fab Flexible Duct Connectors
  • Econ-O-Fab Flexible Duct Connectors
  • Junior Flexible Duct Connectors

Several other companies also produced asbestos-containing HVAC components. Other asbestos ductwork connectors and sealers include:

  • Celotex Carey Asbestos Insulating Ducts
  • Celotex Carey Duct Adhesive (manufactured 1940 – 1955)
  • Celotex Carey Insulation Duct
  • H.B. Fuller Duct Sealer 32-04

Various manufacturers produced asbestos ductwork connectors. Some of these companies also made other asbestos-containing products used in duct systems.

Their use of asbestos in these products put workers manufacturing the goods at risk of exposure. Those who worked with HVAC systems, homeowners and others also may have been exposed to friable asbestos.

Companies That Produced Asbestos Ductwork Connectors

03. Ductwork Connectors & Asbestos Exposure

Who Is at Risk of Asbestos Exposure From Ductwork Connectors?

HVAC workers are among the most at risk of exposure from asbestos duct connectors. Installing or repairing ductwork connectors could cause asbestos fibers to become airborne. Other parts of HVAC systems also often contained asbestos. As a result, HVAC workers could disturb these other products while installing duct connectors.

Any damage, wear and tear or aging to any of the asbestos components in HVAC systems could lead to exposure.

Other building materials, such as ceiling tiles and insulation materials, may also contain asbestos. Workers should be cautious when interacting with these materials while servicing HVAC systems.

Homeowners may also risk exposure to asbestos ductwork connectors. For instance, asbestos paper used as a duct connector can become worn over time. Pieces of the asbestos paper may start to flake off, potentially leading to asbestos dust in the surrounding area.

Occupations at Risk of Exposure From Asbestos Ductwork Connectors

04. Asbestos Lawsuits

Asbestos Lawsuits, Settlements & Other Compensation

Individuals exposed to asbestos ductwork connectors may be eligible for compensation. If these individuals later develop an asbestos-related disease, such as mesothelioma, they may pursue lawsuits and different types of claims.

For instance, victims may be able to file an asbestos lawsuit against the manufacturer(s) whose products caused the exposure.

Sheet Metal Worker Diagnosed With Peritoneal Mesothelioma Awarded Nearly $2M

A California man worked in the sheet metal industry for almost 50 years. During this time, the man worked with flexible duct connectors from Duro Dyne Corporation. Duro Dyne Corporation’s duct connectors and duct sealers contained chrysotile asbestos fibers.

The man claimed he was never advised to use protective equipment when handling the asbestos products. In 2002, he was diagnosed with peritoneal mesothelioma. The man and his wife filed a lawsuit against Duro Dyne Corporation and other asbestos manufacturers. The jury awarded the couple $1.9 million.

Individuals may also be eligible for other types of claims, such as an asbestos trust fund claim. For example, Johns-Manville manufactured asbestos-containing duct connectors. Those who worked with Johns-Manville asbestos products and developed a related illness may be able to file a claim with the company’s trust.

Individuals who develop an asbestos disease after exposure to asbestos ductwork connectors should talk to an experienced lawyer. An asbestos attorney can explain all of their legal options and handle the filing process.

Financial compensation can help mesothelioma victims and their loved ones cover treatment expenses, lost income and other related costs.

05. Asbestos Ductwork Connectors Removal

Safely Removing Asbestos Ductwork Connectors

Individuals should never attempt asbestos removal or encapsulation on their own. Asbestos tape and flexible duct connectors can easily release asbestos dust into the air when damaged or worn.

Individuals should also use caution if they have their air ducts cleaned. Some HVAC companies may recommend regular air duct cleaning every few years. However, the Environmental Protection Agency (EPA) warns knowledge around air duct cleaning is still in its early stages. It’s unclear if cleaning air ducts prevents health problems. As a result, it is too soon for the agency to make a clear recommendation on ductwork cleaning.

However, the agency warns anyone who has their air ducts cleaned should be cautious of the potential for asbestos. A professional should inspect the HVAC system for any asbestos materials before cleaning. They can look for asbestos ductwork connectors, asbestos insulation and other asbestos components.

The EPA states any asbestos materials present should only be handled by specially trained contractors.

Additionally, during asbestos remediation, asbestos abatement contractors should shut off and isolate the HVAC system from the work area. The Occupational Safety and Health Administration (OSHA) recommends sealing ducts and vents with two layers of plastic. This prevents the blower from circulating contaminated air.

The EPA and OSHA have various regulations in place to protect these professionals, other workers and the public from exposure.