Lincoln Helmet Spares FAQs
Spares for one maker's helmets and powered air units: what wears, how to match parts and how to check them.
What should I check on a powered air helmet before each use?

Check the whole unit before you start work, every time. Look over the helmet, hose and filters for damage, confirm the battery is charged, and check that the fan is giving enough airflow before you rely on it. Your manual describes how to test airflow for your unit.
If anything is cracked, loose, blocked or not working properly, replace or repair it before use. A powered helmet protects your breathing only when every part is fitted and working, so never skip the check because you are in a hurry.
What should I do if the fan stops or the airflow drops?

Stop welding at once and leave the work area. Do not keep working if the fan stops or the airflow drops, because the helmet then no longer gives the protection it was designed for. Keep the helmet on until you are clear of the fume, as dangerous contaminants may not be visible or smellable.
Once you are in clean air, check the battery, filters, hose and connections. A flat battery or blocked filter is a common cause. If you cannot find and fix the fault, replace the faulty part with one the maker specifies, or have the unit examined by a competent person before using it again.
Do spare parts affect the helmet's eye protection?

Yes, they can. Welding eye protection, including the filters that guard against arc eye, should conform to the relevant British and European standards, which cover impact resistance, auto-darkening filters and fixed filters. A spare lens or frame that does not match the original may not meet the same level.
Fit parts the helmet maker lists for your helmet, and check the markings on the part against the manual. If you are unsure, ask the supplier or the maker before fitting it. Never use a cracked frame or a part that is not made for the helmet.
What does the optical class on a helmet filter mean?

Auto-darkening welding filters carry an optical class written as four numbers, such as 1/1/1/1. Each number grades one property from 1 (best) to 3: the quality of the view (distortion), light scatter, how even the darkness is across the lens, and how the darkness changes when viewed at an angle. The standard behind this marking has been updated, so newer filters may quote a newer standard.
The first three matter most in everyday welding because they affect what you see all the time. The fourth matters mainly when looking at the arc from a sharp angle. When replacing a filter, check that its class is not lower than the original and that it is intended for your helmet.