Oddly enough it was during a product safety inspection. In the oil and gas industry there are certain items that are so expensive and so critical to operation that getting a defective part is simply not an option. Many large oil rigs generate over $1 million in product every day and having a rig shut down for 12 hours because your product didn't work is like a death sentence in this industry. Safety items also fall into this category because they had better work when you need them to.

Some companies will claim that they tested a product but you can never know for sure if they actually did. Well oil companies like to be sure....most of the time. So what they do is get with a 3rd party inspection company. The inspection company will send a guy out that has to witness you test the product. If you say your product can hold 5,000 psi the inspector has to witness you hook up, pressurize to 5,000, and hold that pressure before you get a passing grade.

Well that's what by friends dad did, he was an inspector. On that day he was inspecting a weld repair job on a huge valve (about the size of a small SUV) that had cracked. The valve was placed inside a testing chamber that looked more like a military bunker. For whatever reason the testing required that the chamber be pressurized to something like 10 psi (no one was inside the chamber). But everything worked great and the valve passed the test. However they couldn't get the door back open, the handles just wouldn't budge. So some of the workers started knocking the handles loose with a big pipe wrench. No one had bothered looking at the pressure gauge to see that the chamber had not been completely depressurized. When that last handle was knocked loose the door, which was made of solid steel a few inches thick, blew open. It ripped the hinges off the chamber and went flying at the guys that were beating on it, killing them both almost instantly. The door went tumbling through a field, took out a few trees before finally coming to a rest about a quarter mile away.

I've heard numerous other stories like this from "old school" oil field guys where people had arms or legs ripped off because they opened the wrong hatch.