Do not twist or bend the tyre valves when attaching a pressure hose or gauge. Doing so may cause damage, leading to tyre failure. Death or serious injury may result.
Keep the tyre valve caps screwed down firmly to prevent water or dirt from entering the valve. Check the valves for leaks when checking the tyre pressures.
Do not use metal valve caps, as these can corrode onto the valve threads and be difficult or impossible to remove.