PM Inspections & Dye Testing

Baghouses are an important part of many businesses. They provide a vital role in keeping both the internal and external factory environments clean.

Catastrophic failure for any piece of equipment is never wanted. This can be particularly true for a baghouse because it can service many production once.

Simple daily in-house inspections can be invaluable. Going to the baghouse and recording the pressure drop reading often pays multiple dividends. If something changes…it can get noticed quickly.

Scheduled Inspections

Frost offers in-depth inspections and audits daily, weekly, monthly, quarterly, semi-annually and annually

Typical Inspections Include:

Cleaning Mechanisms

  • Check all cleaning systems for condition and effectiveness.
  • Check airline supply for pressure and leakage.
  • Inspect any dampers for operating condition, position and sealing.
  • Check all rotating arms, connections, and typical wear points
  • All shaker arms and associated wear points


  • Submit a detailed written report on each compartment/system with all findings, observations and recommendations. Report also includes:
  • General information on each system (Model; serial number; number of bags; etc.)
  • Hot list detailing out all necessary repairs
  • A cell plate map detailing out the location of any noted problems or concerns.
  • 1 hard copy of each report will be sent to Customer within 7 working days of the project completion
  • 1 electronic PDF format document will be submitted electronically

Daily Work Information sheets will be submitted by the foreman to the on-site contact. This will provide an immediate overview of the baghouses.

Dye Testing

The locating of leaking bags is often done through the use of a fluorescent dye powder.

The dye is usually injected in to the inlet air/gas stream of the baghouse.

Once the dye passes through a leaking filter, a trace amount is left as a residue in the clean side of the filter.

This residue is then located through the use of a black-light.

Not all baghouses can be tested this way. The dye will contaminate recycled process powders.

For systems where the baghouse dust is waste or can integrate the powder, this is a very useful tool for quickly finding damaged filters

Dye Test

Scope of Work

Typical Baghouse Inspections include


Visually inspect the filtermedia for cake build-up and condition.  An analysis will be issued for the bags in each system.

Visually inspect filterbags and hardware for condition and installation problems:

Baghouse Inspections
  • Tension
  • Cell plate fit
  • Check access doors for leakage, condition of seal and condition of fastening mechanisms
  • Bag/cage fit

Visually inspect cartridges and hardware for condition and installation problems:

  • Cell plate fit
  • Check access doors for leakage, condition of seal and condition of fastening mechanisms


  • Visually check clean side (plenum) for dust and/or water leakage:
  • All cell plates and cell plate seams
  • All thimbles/connections (as accessible)
  • All wall joints and seams where possible
  • Inspect housings for leakage and apparent weak areas:
  • Major problems to be reported immediately to on-site contact.

Dust Handling System

  • Inspect rotary valves for leakage using a smoke tester (if permitted by Customner)
  • Inspect all mechanical drives
  • Inspect hoppers for product build-up and bridging.
  • Emptying of the hoppers would be an additional cost to this scope

Ducting (based on accessibility)

  • Inspect all duct runs for air leaks and product build-up (where accessible)
  • Review the duct design for potential low airflow zones

Exhaust Fan

  • Visually check outlet stacks for emissions
  • Check belt tension and wear
  • Check sheave wear
  • Inspect inside of fan housing for:
  • Wear in the housing + inlet cone
  • Wear in the impellor
  • Wear of the shaft or impellor/shaft connection fasteners and bearings
  • Grease bearings as needed

Minor Repairs

  • Housing leaks
  • Door seals as needed
  • Ripped or torn bag depending upon quantity and accessibility