Why Didn’t That Burn Down?
Across the world, people are breaking out their air conditioners, fans, and everything they can find to keep cool. Along the way, a few people are going to flip the big switch and have things go wrong. There might be a brief grinding sound before sparks start flying or a loud bang from a worn capacitor blowing it’s top, but nothing deadly happening, just scary things. Things weren’t always built like that. Once upon a time, when things went wrong, they took people with them.
In the early years of electrical equipment, there were no standards or best practices. Electrical fires could be caused by faulty wiring or just faulty-designs. If something like a fan became seized up, there would still be power flowing into it. More power is more heat. Eventually more heat is going to lead to fire or electrical arcing and things are going to go wrong fast.
There could be appliance casings made of metal, with no protections from ground shorts. A power drill could short to its casing and electrocute the user or catch something on fire. There weren’t even ground pins available on most electrical outlets at one point in time, leaving one less degree of electrical protection.
When things went wrong in the old days, they would generally fail with flames or explosions, fail deadly.
Modern Safety Standards
When things go wrong, insurance companies are often left with the bill. This spurred on a need for inspectors and advising, especially around the late 1800s with so much innovation going on. Factories could be built with new technology, new electric motors or new machines, just to burn down weeks later. It was a new type of challenge altogether. In earlier days, safety was just keeping wood away from fire places and pressure relief valves on boilers. Electricity and the industrial age were something altogether new.
This lead to the inception of the Underwriter’s Laboratory around 1893. William Merril Junior stumbled upon the idea of an electrical testing and inspection company, which he proposed to insurance underwriters. Such a company could charge for its inspection services, reduce the chances of bad things happening, and eventually even play a part in identifying the cause of a fire.
Other standards bodies would popup before and afterwards, but the famous UL mark is one that nearly everyone in the US and potentially other countries will have seen hundreds of times. It’s these standards groups that help keep us safe.
Strict, Voluntary Testing
Companies with approved products, whether from Underwriter’s Laboratory or elsewhere, all needed to be thoroughly tested and inspected. This could include attempts to make the equipment catch fire, induce failure, or even studies into the manufacturing process and production defects. Overtime, the standards grew stricter and stricter to pass the tests as more things were found that could go wrong.
These certifications eventually became essential. It could take years for new laws to be written and approved to mandate safer products, but consumers, lawyers, and underwriters were much faster to react. Insurance agencies could raise rates for riskier buildings that hadn’t been inspected. Consumers could refuse to buy products that weren’t tested to be safe, to keep their insurance down. Lawyers would have science to back them up, suing manufacturers for blatantly dangerous products. All of this pressured manufacturers to start making things safer.
How exactly do we make these things safer? Very careful designs. When a capacitor fails, the top will bow out, visibly indicating imminent failure. The top will start to crack and eventually vent the capacitors’ contents, conductive fluids, as mostly harmless gasses (don’t breath the smoke). When a component inside a power drill catches fire, the drill’s casing is usually fire-retardant. Even box fans are safer now than they used to be. There are fuses and short spans of wire that will melt before the fan has a chance to cause significant damage.