Hmmm...I take your point, but I wonder if in practical terms, this has actually had a detrimental impact on the effectiveness of the fire service operationally.
For instance, if on a squad of seven fire officers, one was a woman who was unable to physically carry a 13 stone person down a building, wouldn't practicality kick in (ie. managing the crew, planning, and actually fighting the fire).
With the old rules in place, the service was excluding a whole skillset that could be open to them.
An alternative perspective...
When I was growing up, female door staff were unheard of. Now, when I'm in Soho, I see loads of places that employ female bouncers, not because they're big and tough, but because they (generalisation alert) have great negotiation skills and despite recent news stories - most blokes, even when drunk, will think twice about starting a fight with a female bouncer.