Poor planning and event management, even there the sink is better than many other spots, but good response. The back yard, preferably on a poured concrete slab or masonry patio, a good bit away from the house, with a large fire extinguisher standing by and hose charged would be a better setting.

That said, and out of the way, I have to admit I've run my white gas stoves in the house. The difference being I got away with it.

Dry chemical extinguishers, yuk .... could you describe the cleanup in detail? Was it just one short blast of chemical or did you lay it on thick? Last few cleanups after dry chemical units discharged I was involved in had the powder spread over a huge area. Virtually every horizontal surface, even 50' away, was thick with it.