We define stand by as reporting to the station within 20 minutes of the intial page and staying until IC determines that you are not needed and releases you from the call. The 20 minutes encourages members that live out of town to respond to the station. Although they are not needed the majority of the time, their response has saved us a few times when our normal responders have been unavailable.
Hope his helps.
This is clearly an individual department / administrative decision. A decision that should factor in call volume, personal committment, time, and level of service coverage desired by the Fire Chief.
Now here is my take - If individuals respond back to the station and do not make the apparatus because of the time, travel distance, work, etc. What benefit would it be to the community, if they were allowed to be released to go back to the area for which it took so long to come from to begin with? Meaning overlapping calls, the next out apparatus response would be increased by many minutes.
Now when I was a volunteer, if we missed the truck we were required to remain at the fire station in a state of readiness until the Incident Commander of the original emergency declared his call under control and placed sufficient equipment in service to respond "without delay" for a future call. Once this was done, the station coverage crew was allowed to sign out and be released.
Like previously mentioned, some top responders on paper never go on an actual call but get the same credit as the one's who actually do all the work. My next thought is the top responder may have the absolute least amount of real firefighting experience. Then, if some know they are going to be immediately released, some could play the game to drag their feet and come in, sign in, then go back to whatever is more important to them.
Like I said, your department administrator(s), like the Fire Chief, Chief Officer's, Fire Board, etc. need to create a policy on how they want the fire department to deliver service to the community. If two of you are discussing the interpretation of this now, then you are clearly lacking a clear and concise policy or procedure.