Ma jiro wax kala sareyn ah oo ku jira qiimaynta-ilaalinta qaraxa ee boodhka iyo gaasta, maadaama lagu dhaqmo heerar kala duwan oo heer qaran ah. Shahaadada ka hortagga qaraxa boodhka waxay raacdaa heerka GB12476, halka shahaado-caddaynta-iska-caabbinta gaaska ay raacdo GB3836.
Heerarka kala duwani waxay ka dhigan yihiin imtixaanada la sameeyo inta lagu jiro habka shahaado bixinta way kala duwan yihiin. Sidaa darteed, these two types of explosion-proof equipment are not interchangeable and cannot replace each other.