My father-in-law is one of the captains on the FD in the city I live in. Some of the stories he has told me about "arriving on the scene of an accident involving a motorcycle" are enough to make me want to throw up. Of course he rides a 79 Goldwing and doesn't let his work scare him out of riding. A lot of the guys in the Dept don't ride because of what they see on the job. 
Periodically people express surprise that I ride. "I'm suprised you ride a bike given the things you see as a fireman". Actually, if I were going to use that as a criterion, I wouldn't do much of anything.
Let me give you, perhaps, a different perspective. Firefighting is an inherently dangerous job - one of the most dangerous. Actually, if you were to find a way to normalize the time 'on the job' to 'on the bike' I'm not sure it is not more dangerous than riding a bike. Remember, most firefighters spend the majority of their time waiting to respond, training, etc.- not responding. So if you could normalize the hours on the bike (exposed) to the hours involved in the dangerous aspects of firefighting (exposed), you may be surprised and which is more dangerous. I don't know - I don't have that data. I do know that as Fire Chief I get fire fighter fatality notices from USFA and we are on 80, I belelive, this year. I also know I worry more when in the truck on response than I do on the bike. I could not take the level of stress/intensity that is there during a response for the number of hours I'm on the bike - I would quit riding if that were the case - and perhaps those FF's who do not ride feel that way. (note, some of the worst "wrecks" I've been on were riding horses).
So - firefighting is inherently dangerous. That means a risk adverse person is NOT going to be a firefighter. What we do is work _hard_ to mitigate that risk. We train. We have standard operating proceedures (now called standard operating guidelines - thanks to the laywers). We wear PPE (personal protective equipment) and are VERY strict about that.
Riding a bike is the same to me. I train (practice, make sure I know how to ride). I wear PPE - bright colored riding jacket with armor, helmet, gloves - never shorts and a tee-shirt. I would no more ride my bike without that gear than I would run into a burning building without my PPE on. I have SOG's I follow - standard and trained responses to situations.
I love fire fighting - and will be a FF as long as I'm able. I work hard to make it as safe as possible.
I love riding - and will ride as long as it is practical. I work hard to make it as safe as possible.
Same thing really.
BTW - (I'll probably raise a few hackles here). For those who act unsafely in a car/bike/bicycle/whatever and say "I'm only risking myself" Not true, - when that pager goes off - and we responsd, we are at risk. It is a risk we choose to accept - nobody is forcing me to be a fireman - so I'm not complaining - but it is a risk and so actions taken are not in a vacuum. If you don't want to wear protective gear on the bike - that is your call. But saying you are risking only yourself is not a valid justification.
