Do firebreaks prevent fires from starting?

A firebreak will not prevent a fire from starting in the oxygen tubing or delivery accessory (mask or nasal cannula). It is therefore important that there is no relaxation of any other risk controls applied to reduce the risk of fire. What a firebreak is intended to do is to extinguish a fire that tracks back along the oxygen tubing to the oxygen supply source. This reduces the risk of a fire being spread by the oxygen tubing.