Kevin
We use a HEPA vacuum cleaner to initially extract as much dust and dust mite feces as possible. After that we use dry steam to eradicate live dust mites and finish by spraying on a diluted boron powder that kills off dust mites in the long term by sealing their digestive systems. Boron is a natural element
so usually doesn't affect people with asthma or allergies. This is a system that takes time to work but has a longer benifit.
Harvey