Definition - What does Fire Watch mean?
Fire watch is used in an area that does not have automatic fire warning systems or fire suppression systems. A fire watch is required if any of the fire systems is not working temporality, or if none is in place yet. It is usually only a short-term solution in the interim before the fire systems can be repaired or installed. A responsible person, who must have fire suppression equipment with them, performs a fire watch. The area to be watched for fire is patrolled by the fire watch personnel and action taken in the event of a fire.
Safeopedia explains Fire Watch
Where construction results in the absence of fire systems, fire watch is an essential process. A fire watch is even more important where hot works (work with welding and other fire hazards) is taking place where there is no fire warning system. The fire watch ensures that if ignition occurs, it can be extinguished as soon as possible. Typically, the duration of fire watch is outlined in the hot work permit.