Smoke, Mirrors, and The Miniature Explosion

I recently handled the practical effects for a car exploding in a miniature set, a technique I hadn't fully embraced in years. My main goal was a controlled, safe, yet visually impactful blast. I rigged a small, scale-appropriate car model with a tiny squib (think a small flash bulb from those old cameras, but encased) and filled the immediate surrounding area with a very fine mist from a hazing machine, letting it settle. On detonation, the squib provided the initial flash and 'oomph,' while the settled haze dramatically amplified the visible shockwave and debris cloud, turning what could have been a tiny, fleeting pop into a much larger, more cinematic event on camera. What didn't work as well was my initial attempt to use compressed air for debris dispersal, it was too chaotic and blew the surrounding set pieces away before the squib could even fire, making it look unnatural. The key was the perfectly still, fine haze. It worked a treat, but it got me thinking, for miniature gags requiring more sustained fire, what's a safe, non-toxic, and scale-appropriate method for generating realistic miniature flames without using actual fire risks?