4. Routine maintenance, inspection and operational testing of the emergency generator and associated. components must be overseen by a properly trained person [see MSFC(07), Sec. 604.5; NFPA. 99(99), Sec. 3-4.4.1.1(b)3; NFPA 110(99), Sec. 6-4.7; NFPA 110(02), Sec. 8.4.7].
If rain and wet roads are a concern, you should consider replacing your tires when they reach approximately 4/32 of remaining tread depth. Since water can't be compressed, you need enough tread depth to allow it to escape through the tire's grooves.f two of your tires have a lot of remaining tread depth, but you need to replace the other two because they were damaged or have worn out, you should replace them with a pair of tires that come as close as possible to matching your existing tires.
Compressed Air v Nitrogen. Aircraft and racing car tyres have been using purified nitrogen to inflate tyres for years as tyre pressure is reduced at a much slower rate. The compressed air which is usually used to inflate tyres is made up of 78% Nitrogen, and also contains Oxygen and water vapour. Once your tyres have been filled with Nitrogen it is important that you only use Nitrogen when topping up. 2  If you are in a situation where you can only re-inflate with compressed air you must deflate the tyre fully before you can re-inflate with Nitrogen.