Although the United States has no legal requirements for product safety, codes in some larger cities allow only listed products to be used in some jurisdictions. Indeed, if you ask UL or one of the NRTL laboratories if your product needs to be approved, they will almost always say yes.
Most companies seek approval for their products to meet liability concerns or satisfy their market.
Europe and Canada, for example, require product safety testing and marks on products made or sold there, and any company wanting to export goods to those markets must comply. With increasingly fierce competition, companies can no longer rely on reputation or unsupported claims. The CB test report must be completed by a laboratory that is recognized as a certified body by the European Union. More than thirty countries accept the CB scheme as proof of a recognized testing method. Additional requirements for other countries will be minimized.