Baghouse leak testing, found under UV light.
A fluorescent powder leak test finds holes, torn seams and poor bag-to-tubesheet seals by injecting a coloured tracer powder into the dirty-gas side and inspecting the clean-air plenum under UV light. Wherever powder glows on the clean side, dust is leaking. Masturlal runs these tests at commissioning, after change-outs and when emissions rise, and documents the results for environmental compliance audits.
- Method
- Fluorescent powder and UV lamp
- Output
- Leak map, photographs, compliance pack
When to run a leak test
- At commissioning, after new bags are installed
- When opacity or stack emissions start to rise
- After a partial change-out, to check the new bags are seated
- As part of an annual maintenance contract
How the test works, step by step
- Prepare. Empty the hopper, stop the cleaning system and leave a light dust cake on the bags.
- Calculate the dose. Work out the total cloth area. A common guide is about 1 kg of powder per 100 m² of cloth; the powder maker's figure governs.
- Inject. With the fan running and cleaning off, inject the powder evenly into the inlet duct close to the baghouse.
- Shut down safely. Stop the fan, isolate and lock out, and follow confined-space entry rules.
- Inspect. In the clean-air plenum, scan bag tops, seams, snap bands, tubesheet welds and door seals with a UV lamp.
- Repair and retest. Replace or reseat the faulty bags and repeat the test with a different powder colour to confirm the fix.
What the glow tells you
| Where powder shows | Likely cause | Fix |
|---|---|---|
| Ring around a bag top | Poor snap-band or tubesheet seal | Reseat the bag; check the tubesheet hole |
| Along one bag seam | Seam failure | Replace the bag |
| Spot on a bag | Hole from abrasion, burn or a cage defect | Replace the bag; inspect the cage |
| Tubesheet welds or joints | Structural crack | Weld repair |
| Door and hatch edges | Worn gasket | Replace the gasket |
What you receive
- A leak map by row and column
- Photographs of every leak found
- Opacity baseline and emissions sign-off
- A documentation pack for environmental compliance audits
Safety notes
- Check the powder safety data sheet and its compatibility with the process.
- Assess combustible-dust risk before injecting any powder.
- Follow lockout, gas testing and confined-space procedures before entry.
- Wear UV eye protection and respiratory protection.
Questions, answered.
How do you find a leaking filter bag?
The most reliable method is a fluorescent powder test: inject tracer powder upstream, then look for glowing powder on the clean side under UV light. The glow marks the leak.
How often should a baghouse be leak tested?
At commissioning, after any change-out, whenever emissions rise, and at least once a year as part of maintenance.
Can you leak test while the collector is running?
Powder is injected while the fan runs, but the inspection itself is done with the collector shut down and locked out.
Send us your dust profile.
Temperature, chemistry, moisture, particle size and your emissions target. An application engineer replies within one working day, usually with a media specification within two.