One of the most important, if not most important, pieces of equipment used frequently by firefighters is the mask. There are some non-essential pieces of fire equipment; masks are not among them.
You should always regularly check your own mask, so you can be safe in the knowledge that it’s going to work properly when you need it. Make sure you check the whole mask, especially the cylinder to ensure that it is full to maximize your operating time. A mask not full to the max with air means less operational time.
Make sure that all the straps, including the straps on your face piece, are correctly adjusted to suit your needs. And, open the cylinder valve fully whenever turning the mask on. Not having the cylinder fully opened can result in a sudden loss of air when operating.