This is true but I guess you volunteer the time you have and if you cant spare the time for a strike team or a job that maybe several hours guess you should be able to choose.
I guess If you just got the tone and had to rock up there maybe times where you drop stuff your doing head to station then have to tell Cap or Lt that you cant go as you don't have 4 hrs etc... This maybe a problem in some cases say needing one to roll truck and that one wants to go as they don't have the time to give for strike team but a MVA or small fire they would have gone!!???.
I think the message is a good idea for above reasons but can be bad in the fact people choose... Guess other thing is to if you don't want or feel comfortable with MVA you have that choice too.
What might be an Idea is if you could somehow hook up a truck / trucks rolling so people can get idea if more needed or all go and you can return home type thing... I know there is manual turnout option for no crew but must be frustrating for the people I see at our station that just miss truck as we crewed or rolled after a acceptable time and they just didn't get there in time...
guess a more complex version which we may see someday is that you hit a button on pager if you are attending so the station has idea of numbers coming or personnel responding!!???
yep here (duh hear) ya $$$$$$$$$ as pages would have to talk not just listen... but maybe could be done through mobile network and sms
just some of my thoughts and ideas off top of head thinking allowed (doh aloud).. for better or worse!!
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