Following the final vacuum sampling, each of the treated carpet squares was further assessed for the presence of live mites using the heat escape melhod of BischoiT and Fischer [18]. The underside of the carpet squares was heated on a hot plate at 80 C for 15-30 min. Live mites, if present, move away from the heat source and are eaptured on strips of transparent adhesive tape laid over the lop surface of ihe carpet square. We used 3 X 100 cm' strips of tape per square, which were removed after heating and examined under a stereo- binoeular mieroseope for the presence of live mites.