What is lens cleaning?
Removing the film, dirt and deposits from the lens of an airfield light so the full beam leaves the fixture cleanly. The lamp or LED can be perfect and the light still looks weak if the lens is dirty.
The lens is the last part the light passes through, and the first part to get dirty. Dust, soot, jet-blast film, grass and, on inset lights, rubber from landing tyres settle on it. Each layer absorbs and scatters light, so the intensity drops and the beam can lose its shape. A clean lens brings back the output the fixture was built to give.
1Make it safe first
Isolate and lock out the circuit before touching the fixture, as your site procedure requires (see Safe Maintenance Sequence). A lamp-based fixture can be hot, so let it cool. Work on the airfield only with the right permission and under the site’s safety rules.
2Clean the lens the right way
Brush off loose grit first so it does not scratch the lens as you wipe. Then use the cleaner and cloth the manufacturer approves, usually a soft, lint-free cloth with water or a mild cleaner. Rubber deposits on inset lights need the approved removal method. Do not scrape, and do not use abrasive pads or strong solvents: a scratched or crazed lens scatters light for good and cannot be cleaned back.
- Brush off loose grit before wiping
- Use maker-approved cleaner and cloth
- Refit anything you removed
- Scrape or use abrasive pads
- Use strong solvents on the lens
- Force cleaner or water past the seal
3Inspect and record
With the lens clean, look for cracks, chips, scratches, crazing, a damaged seal, water or condensation inside and a shifted alignment. Check that nothing was knocked out of position, confirm the light works, compare its brightness with a neighbouring clean fixture, and record the condition and the work done. A damaged lens is a fault to report, not just dirt.
| Item | What to do |
|---|---|
| Lens surface | Where the light leaves; keep clean and unscratched |
| Loose dirt and grit | Brush off first so it does not scratch the lens |
| Film and soot | Wipe with soft cloth and approved cleaner |
| Rubber deposits | Inset lights, mostly in touchdown areas; approved method only |
| Seal around the lens | Check while cleaning; keep water out |
| Lens condition | Cracks, chips, crazing or scratches mean report it |
| Circuit | Isolated and locked out before work |
| Record | Note condition and what was done |
Frequently Asked Questions
Q1Why does an airfield light lens need cleaning?
Dust, soot, jet-blast film, grass and, on inset lights, rubber deposits settle on the lens. They block and scatter part of the light, so the fixture looks dim and the beam can look uneven even when the lamp or LED is healthy.
Q2Should a lens be cleaned with the circuit live?
No. Isolate and lock out the circuit first, as the maintenance plan and site safety rules require. A lamp-based fixture can also be hot, so let it cool before touching the lens.
Q3What can be used to clean an airfield light lens?
Use the cleaner and cloth the manufacturer approves, usually clean water or a mild cleaner with a soft, lint-free cloth. Abrasive pads, scrapers and strong solvents can scratch or craze the lens and lower its output for good.
Q4How do you remove rubber deposits from an inset light lens?
Use the method and product the manufacturer and your maintenance plan approve for rubber removal. Do not scrape or use harsh solvents, which can mark the lens, and check the lens surface afterwards.
Q5What should be checked after the lens is cleaned?
Look for cracks, chips, scratches, crazing, a loose or damaged seal, water or condensation inside and a shifted alignment. Then confirm the light works and record the condition and the work done.
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