[pat in Santa Cruz]

We had an engine fire once at a place I worked. The dry extinguisher put it out pronto. There was powder all over the shop, not just the engine. It took some sweeping, dusting, vacuuming, washing and a wipe down with a wet rag to clean it up. But, given the alternative of an out of control fire, it was worth it. A wet chemical extinguisher would probably make a different kind of mess, but it would still have to be cleaned up. It might not drift all over the shop like the dry chemical did, though.