Anyone built their own system for getting fresh air under their helmets to keep positive pressure so fumes are less likely to enter lungs? Considering something like a bathroom exhaust fan with duct work, but seems it will dry eyes and be distracting. I wear reading glasses when welding, might do better to buy a magnifying lens for the helmet. Ususally working with stainless, mainly as a hobby. Try to avoid the fumes, often holding breath and / or using a under helmet carbon filter. Can't help but wonder if some of the chronic joint pain is a result of chromium.