We get asked about noisy pipes endlessly so heres the answer
Theres is no decibel test! There is no requirement for a BS stamp or E mark If your exhaust can has “not for road use” or “for race use only” or something similar stamped on it, its an RFR (reason for refusal) or a fail in english : ….. in theory if you stick a bit of tape over the offending words i cant remove it so cant see it & cant fail it….. but ……..
…. its ultimately down to testers discression eg if i think its too loud its a fail.