The technological revolution of the late 19th century brought with it the electrification of the country. Assembly lines enabled the mass production of materials, consumer goods and machines of all types. Goods and machines became so complex that consumers could no longer determine if they were safe to live with and use. Manufacturers were assembling machines from parts, bits and pieces purchased from suppliers.

Consumers, who hadn’t the desire nor time to learn the intricacies of electricity, wanted to know that the machines they purchased for their homes were safe. They wanted assurance that an electrical fire wouldn’t burn down their homes while they slept. Manufacturers wanted to quickly source the parts and assemblies that they needed from suppliers without going through the time and expense of testing the products for suitability. Insurance company underwriters wanted a method of reasonably quantifying the inherent risks of what they were insuring.

These needs drove a new specialized industry: establishment of manufacturing and safety standards, and the testing of materials and products to ensure that they meet those standards. One of the first businesses to establish fire and electrical safety standards was the Underwriters’ Electric Bureau, of the National Board of Fire Underwriters, in 1895. This company has since evolved into Underwriters’ Laboratory (UL). UL is one of the best known and trusted international standards setting and testing laboratories today. There were more than five nationally recognized standards addressing the safe use of electricity and electrical machines by the end of the 19th century. The proliferation of electrical standards became a nightmare for manufactures, electricians, insurers and consumers.

The “Joint Conference of Electrical and Allied Interests” formed from several national organizations to develop a common set of electrical standards in 1896. The draft standards were sent out to over 1,200 stakeholders in the United States and Europe. Stakeholders’ comments drove debate and changes to the initial document. The result was adopted by the National Board of Fire Underwriters in lieu of its own standards. The final standard became the National Electric Code (NEC) of 1897.

Another group of insurance underwriters were meeting in New York at the same time to set a unified set of standards addressing sprinkler fire protection systems. The National Fire Protection Association (NFPA) was created out of this effort. The National Board of Fire Underwriters joined the NFPA in 1900 putting the development of consensus standards addressing electricity and fire protection under one body.

This created a system where certification organizations like UL generate testing standards to ensure that materials and products meet industry consensus standards developed by bodies like the NFPA.

Some examples of these standards (and there are hundreds more):

• NFPA 70, National Electric Code (NEC)
• NFPA 37, Standard for the Installation and Use of Stationary Combustion Engine and Gas Turbines
• NFPA 70B, Recommended Practice for Electrical Equipment Maintenance
• NFPA 70E, Standard for Electrical Safety in the Workplace
• UL 4, Armored Cable
• UL 489A, Circuit Breakers for Use in Communications Equipment
• UL 514B, Conduit, Tubing, and Cable Fittings
• UL 817, Cord Sets and Power-Supply Cords
• UL 514D, Cover Plates for Flush-Mounted Wiring Devices
• UL 50, Enclosures for Electrical Equipment
• UL 1660, Liquid-Tight Flexible Nonmetallic Conduit
• UL 2200, Stationary Engine generator Assemblies

UL has an interesting graphic timeline posted on their website. For more historical information, along with a video, about the NFPA visit their website.

Many years later, the Occupational Safety and Health Administration (OSHA) promulgated regulations requiring that electrical generation and distribution equipment used in workplaces be certified and listed by a nationally recognized testing laboratory (NRTL) like UL. OSHA has also increasingly based its own regulations on industry consensus standards like those of the NFPA, sometimes adopting them in whole as additions to workplace safety regulations in 29 CFR §1910.6.