ETL SEMKO (formerly Electrical Testing Laboratory) is a division of
Intertek Group plc (LSE: ITRK) specialising in electrical
product safety testing, EMC testing, and benchmark performance testing. ETL SEMKO operates more than 30
offices and laboratories on six
continents.
SEMKO (
Svenska Elektriska Materielkontrollanstalten "The Swedish Electric Equipment Control Office") was, until 1990, the body responsible for testing and certifying electric appliances in Sweden. The "S" mark was mandatory for products sold in Sweden until the common European
CE mark was adopted prior to Sweden's accession to the
European Union.