In an extensive district fire, the individual BA firefighters must be relieved.
This can be done ‘at the nozzle’, i.e. the replacement firefighter can directly
take over the equipment being used by the present firefighter. This type of
takeover normally only requires a couple of minutes and the delay it causes
seldom results in any significant problems.
Later during the same response operation there is a need to relieve a whole
unit – personnel are tired, cold and hungry. The equipment is worn and needs to
be replaced. This type of takeover takes longer, perhaps 30 to 60 minutes.
Still later in the course of events it becomes necessary, for some reason, to
replace (or transfer) a complete sector, involving many personnel. This type
of adjustment can take several hours, not least because of transportation. The
delays caused by such a move can, in a worst case scenario, result in the total
failure of an operation and must be planned for very carefully.
Regardless of how long the delay is, the reduction in emergency
preparedness, among other things, must be taken into account. There is
a limit to the number of personnel available and the longer it takes to
conduct relief replacements the greater can be the reduction in emergency
preparedness.
Example 9