In 1896 Edison established a Lamp Testing Bureau within his manufacturing facility, then called the Edison Electric Illuminating Company.
His vision was to provide assurance to consumers, through various product performance and safety tests. Before long, it was well known through various promotions that lighting products manufactured by Edison's company had been tested and proven to meet established (but not yet official) requirements. Almost immediately, many of Edison's competitors, like General Electric, recognized the value in this service and used the testing and verification services of Edison's Lamp Testing Bureau to bring more value to their own brands.
Independence
The basic principles of Edison's third-party lamp testing methods remain the same today. Experts monitored lamps and bulbs to determine how long they would burn, the luminous intensity and if everything burned as it should - without combustibility or explosion. Edison and his staff developed test methods and standards for consistency of each product evaluation.
As Edison and his competitors' product designs were modified for better performance and greater safety, the Lamp Testing Bureau set forth to devise even more stringent testing methods to verify that the products were safe and did, in fact, perform as manufacturers said they would. Eventually, word of Edison's rigorous testing requirements reached consumers, and many soon replaced candles or gaslights in their homes with electric lights where electricity was available. Independent testing of lighting products was a reality for the first time, and manufacturers reaped the benefit of third-party verification.
Soon after, the use of certain electrical testing equipment involved in the lamp testing procedures led to calls for services to determine the safety and perfomance of those instruments, and occasionally Edison's lab was requested to evaluate the performance of some entirely new electrical devices. In response to broader demand for testing services, Edison renamed his testing business unit in 1904 to more clearly identify its purpose. Electrical Testing Laboratories (ETL) was its new name.
Tradition
Today, nearly a century later, Edison's "ETL" brand lives on as a result of Edison's continued success in product testing throughout his lifetime and the ongoing effort of his colleagues, who maintained his companies with the same testing integrity after Edison's death in 1931.
Edison's testing organization, which first helped to calm the fears of safety-conscious consumers through product certification and verification, is now part of Intertek.
