Electrostatic Precipitators — Asbestos Exposure Crosswalk

What This Equipment Is

An electrostatic precipitator (ESP) is a large air-pollution control device that removes fly ash and particulate from flue gas before it reaches the stack. Flue gas passes between high-voltage discharge electrodes that ionize the particulate; the charged particles then migrate to grounded collector plates, where they accumulate until rapped loose into collection hoppers below.

ESPs are huge — a single power-plant unit can be hundreds of feet long, dozens of feet tall, and contain thousands of square feet of collector plates. They operate at flue-gas temperatures (typically 250–350°F at the inlet) and are heavily insulated externally to maintain that temperature, prevent acid-dewpoint corrosion, and protect maintenance workers from the casing.

The asbestos exposure pathways center on:

  • Casing insulation — block insulation jacketing the entire ESP housing, often hundreds of feet of perimeter
  • Hopper insulation — block insulation on collection hoppers below the casing
  • High-voltage bushing insulators — the ceramic / mica / asbestos-millboard components that pass high voltage through the casing wall to the discharge electrodes inside
  • Inlet and outlet ductwork insulation — see Breechings
  • Gaskets — access doors, inspection ports, expansion-joint covers

Why Precipitator Work Was a High-Exposure Activity

Major ESP work happens during boiler outages. Casing insulation gets stripped and replaced when ductwork is modified, when the casing is patched for corrosion, or when entire units are rebuilt. Internal work — replacing collector plates, repairing rapper systems, cleaning out fouled hoppers — requires workers inside the casing, often in heavily insulated and cramped spaces.

ESP rebuilds during scrubber additions (large 1970s–2000s emission-control retrofits) drove substantial peak insulation-removal exposure as entire upstream and downstream sections were reconfigured.

Manufacturers Named in Litigation Involving Precipitator-Adjacent Insulation

  • Research-Cottrell — ESP OEM named in installation/maintenance claims
  • American Air Filter / AAF — ESP and air-filtration products
  • Western Precipitation — ESP equipment
  • Johns-Manville — block insulation, pipe covering
  • Owens-Corning / Fibreboard — block insulation
  • Eagle-Picher — insulation products
  • Pittsburgh Corning — Unibestos insulation
  • Armstrong World Industries — calcium silicate insulation

Documented Product References

Images sourced from publicly available product-identification reference materials. Inclusion does not constitute a finding of liability against any company.

Trust Funds That May Apply

  • Manville Personal Injury Settlement Trust
  • Owens-Corning / Fibreboard Asbestos PI Trust
  • Eagle-Picher Industries PI Settlement Trust
  • Pittsburgh Corning Corporation Asbestos PI Trust
  • Armstrong World Industries Asbestos PI Settlement Trust

Trades Most Exposed at Precipitator Work

Insulators (Heat & Frost), boilermakers, iron workers and welders on casing modifications, electricians working on rapper systems and high-voltage bushings, laborers and contractors handling outage work, demolition crews.

Jobsites in the Network Documenting Precipitators

Compiled from publicly filed asbestos litigation, EPA / state-DNR records, and industry-publication histories. Product and company references reflect what has been alleged or documented in publicly filed litigation. This page does not constitute a finding of liability against any company. Not legal advice; consult a licensed attorney about your specific situation.