Cleanest pit I have ever seen. The one in garages where I had work done in the 50's were a death trap. Lots of grease and oil and only one way out and most mechanics smoked. That being said, I necer heard of anyone dying in a grease pit fire. A mechanic I knew, that lived with his wife and 3 yr old boy in an apartment over the garage, was almost killed by his wife after he let the toddler slide down the grease pit stairs.
I was involved in an truck alignment/frame straightening pit fire in a Ford dealerhip where I worked in the early 60's. I was at the service desk when I heard the mechnaic yell "fire". He had been using a torch to heat a frame when the fire erupted and he was caught between the fire and the blind end of the pit. Luckily, I was able to grab a nearby extinguisher and everything ended well. Anyway, that's a great picture. Thanks for posting it.