The United Association of Plumbers, Pipefitters, Steamfitters and Service Mechanics (UA) is one of the foundational construction unions in North America. The parent organization was chartered on October 11, 1889, in Washington, D.C., and today maintains its international headquarters in Annapolis, Maryland. From the earliest years of the modern American industrial economy, the UA’s members built and maintained the pressurized, thermal, and process piping systems that ran every powerhouse, refinery, chemical plant, steel mill, hospital, university, naval vessel, and commercial building in the country.

The craft is organized around several overlapping classifications — plumbers (potable water, drainage, waste, and vent), pipefitters (process piping, hydronics, and pressurized systems), steamfitters (high-pressure and superheated steam systems), HVAC/refrigeration mechanics (chilled-water, refrigerant, and glycol systems), and welders (certified pressure-vessel and code-piping welders under ASME B31.1, B31.3, and Section IX). UA members cut, threaded, welded, bolted, hangered, insulated, tested, and commissioned every category of pipe that moved steam, water, condensate, feedwater, fuel oil, natural gas, process chemicals, cryogenics, hydraulic fluid, and refrigerant across the U.S. industrial base.

The asbestos era

From roughly the 1930s through the late 1970s, virtually every pressurized and thermal piping system that UA members built was covered, gasketed, and packed with asbestos. Steam and hot-water lines were allegedly wrapped in asbestos pipe covering (calcium-silicate block and pipe insulation, air-cell corrugated paper wrap, and molded amosite/chrysotile sections). Every flange in a steam, condensate, or process-piping system was allegedly sealed with an asbestos sheet gasket or asbestos spiral-wound gasket. Every valve stem in a high-pressure steam or process service was allegedly sealed with braided asbestos valve packing. Every expansion joint on ductwork and process piping was allegedly fabricated from asbestos cloth.

The trade did not choose this. Members were dispatched to jobsites where the specifications called out asbestos pipe insulation by product name (Kaylo, Unibestos, Aircell), where the flange bolt-up torque tables assumed an asbestos gasket, and where the mechanical seal drawings called for a specific asbestos valve packing set. UA members cut asbestos pipe covering to length with keyhole saws and utility knives. They broke old asbestos gaskets loose with wire brushes and scrapers during tie-in and turnaround work. They repacked asbestos valve stems by pulling old braided packing out with a packing puller and installing new asbestos rings from the shop stockroom.

Pipe covering, gaskets, and valve packing — the defining exposures

The characteristic exposure profile of the UA pipefitter/steamfitter/plumber is not one activity — it is the continuous, daily, career-long contact with asbestos in three product categories:

  • Asbestos pipe covering. Cutting a section of Kaylo or Unibestos to length allegedly aerosolized dust directly into the worker’s breathing zone. Re-cutting an existing covering to permit tie-in of a new branch line allegedly generated the same release. Removing degraded asbestos pipe covering during outage work allegedly produced the highest fiber releases of the trade.
  • Asbestos flange gaskets. Every time a UA fitter broke a flange to tie in, repair, or replace a section of pipe or a valve, the old asbestos gasket had to be scraped off both flange faces. Wire brushing and scraping dry asbestos gasket residue on a hot flange allegedly generated substantial airborne fiber. The new asbestos gasket was then cut to size at the jobsite from asbestos sheet stock — again releasing fiber.
  • Asbestos valve packing. Steam-service valve stems leak. Repacking a leaking valve — pulling the gland, removing old braided asbestos packing with a packing puller, and installing new asbestos rings — was a routine maintenance activity performed thousands of times over a UA member’s career.

The Selikoff mesothelioma record

Dr. Irving Selikoff’s Mount Sinai occupational-health research group documented, across a series of foundational studies beginning in the 1960s and continuing into follow-up cohort work in later decades, that pipe-trade workers — steamfitters, pipefitters, and plumbers — were allegedly among the trades with the highest occupational mesothelioma incidence rates of any craft in the American industrial workforce. The pathway was the daily, cumulative contact with asbestos pipe covering, asbestos gaskets, and asbestos valve packing across an entire career.

Allied trades

UA members worked alongside several allied crafts that share parts of the asbestos exposure history:

  • Heat & Frost Insulators (HFIAW) — the trade that installed the asbestos pipe covering after the UA fitter set the pipe; frequently working on the same scaffold at the same time
  • Boilermakers (IBB) — building and rebuilding the pressure vessels the UA piped into
  • Sheet Metal Workers (SMART) — fabricating and installing HVAC ductwork with asbestos-fabric expansion joints
  • Bricklayers / Refractory Masons (BAC) — rebuilding the refractory linings behind the burner piping the UA installed
  • Ironworkers — setting the structural steel that carried the piperack

The UA trade allegedly has a documented mesothelioma incidence well above the general-population baseline, driven by daily contact with asbestos pipe covering, asbestos gaskets, and asbestos valve packing across the full duration of a member’s career.

Today

Asbestos has been substantially removed from pipe insulation, gasket, and valve-packing formulations since the late 1970s and early 1980s, replaced by calcium silicate without asbestos, aramid and graphite gaskets, and PTFE and graphite valve packing. UA members who entered the trade in the mid-1980s or later worked through a substantially safer materials regime. But the disease tail of the asbestos era continues. Pipefitters, steamfitters, and plumbers who entered the trade in the 1950s, 1960s, and 1970s — now in their 60s, 70s, and 80s — are the population now being diagnosed with mesothelioma and other asbestos-related diseases at the highest rates.

This site exists to document that history and, where applicable, to help affected UA members and families navigate the claims process under the asbestos bankruptcy trusts and state-specific litigation frameworks that compensate workers and survivors of asbestos exposure.

Free, confidential case evaluation: Speak with O’Brien Law Firm — (314) 936-2956

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