And while the European type-approval system is nominally more resistant to compliance-shopping than the American self-certification system, manufacturers find ways to circumvent stringent safety performance regulations. With more and more countries signing the UN ECE 1958 agreement, there is increasing disparity between the most fastidious and the most lax testing facility. These newly-joined countries, in many cases, have no domestic auto industry of their own, and today’s highly competitive and cost-sensitive market has created the temptation to shop for a lab that’ll pass questionable or even demonstrably noncompliant lamps.
Despite the effort governments and engineering consortiums put into automotive lighting regulations and test protocols, compliance issues continue to make problems. In the US, multiple-emitter LED rear lamps are widely available in the 4” (100mm) round format most popular on trucks and buses. These have raised concern with regard to the US requirement for a certain minimum lit lens area, because of the dark bands in between the bright emitters. However, because the regulatory text was written with the uniform lens illumination from a filament bulb and reflector in mind, the rules are ambiguous when interpreted relative to more recent technology such as LEDs.