Ngwaahịa a dabara na ọkọlọtọ ule EN149: ngwaọrụ nchekwa iku ume-nzacha mgbochi irighiri ihe nkpuchi; Ụkpụrụ na-emekọrịta ihe: BS EN149: 2001 + A1: 2009 Ngwaọrụ nchekwa iku ume-nyocha mgbochi ihe mgbochi ihe nkpuchi chọrọ akara 8.10 mgbochi ule, EN143 7.13 na ụkpụrụ ule ndị ọzọ.
Ụkpụrụ nyocha nke igbochi: a na-eji ihe nzacha na ihe nkpuchi na-egbochi ihe nzacha iji nwalee uzuzu a na-anakọta na nzacha, ume iku ume nke nlele ule na ntinye ntinye (permeability) mgbe ikuku na-agafe na nzacha site na mmiri ara na ụfọdụ. gburugburu uzuzu ma rute ụfọdụ nguzogide iku ume.