hetkind, your right to a certain extent, depending on the state's laws, what insurance companies deem and how or what your working on or plan to work on over the pit, with farm, semi's, trailers or construction equipment or even vehicles for that matter, my insurance company didn't have a set criteria to go by, they claimed there was no added risk or threat, it never affected my insurance at all, and ironically no ventilation was required. I didn't hard wire lights in, so no code was needed for that, basically nobody I talked to liked any that were hard wired in, they never shined where you needed light anyhow, glad now I didn't hard wire any in, my opinion is, they'd be completely worthless at best if I had done it. I wasn't required to have ventilation in the pit either, but I did put in a natural draft ventilation line where I could put in a fan if needed, turns out I never will, I have far too much the way it is and have to tape over the ventilation lines to partially shut them down, full open and you'd never get a cigarette lighter to light with the suction in the pit.
I had an insurance audit done before I put in a pit, basically someone from the insurance company comes out, does a sit down with you and you hash over the idea, the explanation I got from them was, if your concerned about toxic fumes and dying in the pit, you've got far more problems than just the service pit to worry about, most likely you'd be dead on the shop floor anyhow, long before the pit was an issue. Now if you work on or plan to work on painting equipment or trucks carrying chemicals, then maybe, but for my full line of equipment I own, which they went over piece by piece and asked what others I planned on buying or working on, nothing ever registered as a possible suspect for an issue. Now that said, I also don't run machines in the shop hours on end while in the pit either, nor in the shop without a hood on them, so it was a mute point is how it was explained to me and still feel to this day.
I'd been told by dozens of people what a bad idea it was to put in a pit, said I'd die like everyone else who's ever had one, so I asked both the state and my insurance company for data of deaths or injuries sustained while working in a service pit, both had nothing to back it up for "my" type of work I'd be performing, other types they had some, and most everyone was doing something they shouldn't be doing when a problem came up to cause the statistics. My insurance company told me, it was about like dropping a dozer on yourself and dying from that cause, it happened on the shop floor, thus all shop floors should be banned kind of thinking, we'll forget the fact in order to actually drop a dozer on yourself, maybe you were not doing something right in the first place and maybe you were not where you should have been that was safe, but blame it on the shop floor, it was the cause, and that was a direct quote from an insurance company rep I spoke with and his analogy of the thinking of some as to not put in a service pit.
Before ever putting one in, I'd contact both the state and insurance company and even the city if you live in a city and ask about requirements or codes you need to know about, and get everything up front first, then proceed. Your state, location, insurance, everything might be different, same goes for what your working on, but for me, none of those issues applied or were a factor, now if you consider safety as the issue, I'd take the pit any day over working under a machine blocked up, or laying on a creeper on the shop floor, but that's just me. As for not being able to get out from under whatever is parked on the pit, chances are if you drive the piece over the pit, and can't get out, there's a good chance your not going to get into the pit in the first place due the machine being parked in the way. Now if you have someone else drive the machine over the pit and your in it, my question is, would you lay on the shop floor as someone drove the machine over you to save crawling under it??
I'm not really sure how anyone gets so much contaminates in the sump, doesn't anyone use containers to collect used oil they are draining out of the machine and just dump it in the pit floor?? As for washing off machines, do you guys collect all the wash water outside the shop and filter that?? If this is such a big issue, pump the sump water outside on the wash bay floor and do the same thing as you do with the wash water, which is in most case's let it run or collect in a huge wash vat to be pumped out and dumped via a septic service is what is done around here, then run into a waste treatment facility that way. I'm not sure how most do it, but we generally wash the stuff off first before putting it over a pit, collect waste oil as we go, and when done, maybe some is spilled and we use dirt or floor dry to clean it up, no different than the shop floor, where does all this contaminates come from?? And all toxic fumes, someone has to explain this to me, since neither the state or my insurance company had any hard data as to deaths or injuries that were caused by the use of a service pit, ironically nobody that warned me, had any name or incident either that stated specifically the pit was the cause when used properly, some whom had total brain farts, but they'd have died even without the pit involved.