I've done a lot of work with consumer products, some for the US Consumer Product Safety Commission, some in litigation support, and some for manufacturers or importers seeking an unbiased eye for customer return evaluation.
If a customer returned a product with the plug looking like this (25 kB JPG), or a strain relief that had done this (38 kB JPG) would you panic? Perhaps there is no need. I've seen many examples of frighteningly damaged electrical plugs in which the fault was not the product, but a metal object falling on partly exposed plug blades. Blame Thomas Edison: modern US plugs have a loooong history. The design is awful, but we're stuck with it. And no cord is indestructable, although some are definitely better than others, and strain reliefs vary greatly in their effectiveness.
I've seen products which a consumer deliberately burned, products obviously overheated from an external source such as a nearby lightbulb, products with cut or crushed cords, and a plethora of other alarming-looking conditions which were not the fault of the manufacturer.
I've also seen a few which warrant a recall. I really hate telling people they've got such a case, but if they need to hear it, they need to hear it.
I am not a fire investigator per se. I do have a lot of experience investigating consumer product and electrical equipment involvement in fires. Where a fire investigator is trained in detecting the "usual" causes of fires, I know a number of oddball specific causes. I'm also good at performing tests on fire-damaged and exemplar products, including setting up simulated fires. I can bring to bear a number of examination tools, such as radiography (35 kB JPG), chemical analysis, electron microscopy, etc., not available to many field investigators.
First off, if you're looking for a "hired gun", keep looking. That's not what I do. Hire me to learn the facts. If you don't like what I find, pursuant to a legal investigation, that's "privledged and confidential information."
I've worked on many legal investigations over the years. I've been deposed on only a handful of those cases. I've made it into court only once (the other side lost). Because I stick to hard technical facts, not opinion, my clients generally either know they don't have a case, or know they have a strong one. If I find myself in a courtroom, resorting to "opinion", I've not done a very good job.
I am one of the world's foremost leading experts on one line of automatic drip coffeemakers. The company sold the line, and it is no longer produced, but a huge number of them were made, and a lot are still in service in spite of well-publicized recalls.
In fairness to the manufacturer, the units turned out to be considerably more durable than expected, and that, in large part, led to the problem. The back-up protective component, the thermal cutoff (TCO), malfunctioned in a small but troublesome fraction of these appliances, and this was, at least partly, age-related. There was also some dispute between the parties concerned as to the means of installation and testing, who had recommended what, etc.
After investigating several models of this manufacturer's coffeemaker that had been involved in fires, plus several other manufacturer's models, I had the unusual opportunity to examine hundreds of recalled units. As a result, I've probably seen about as many ways to harm one of these coffeemakers as anyone outside of that company.
The snap-disk bimetallic thermostats used in these and many other appliances have several possible failure mechanisms, but the one I saw the most was for the disk to split. This caused failure-to-open, hence runaway heating, about half the time, and so the TCO was called upon to prevent a fire. Thermostat failure was a very common end-of-life event in these durable products, and that became more true as the manufacturer improved other aspects of the design. Improving a valve so that it was not so prone to clogging may have been their undoing!
There are two ways to rig the "keep-warm" feature of drip coffeemakers. The elegant way is to have two heating elements, a powerful one for making the coffee, and gentle one in the base on which the carafe sits. When the coffee has been made, the main heating element turns off and stays off. Not only does this reduce the number of operating cycles on the thermostat, it usually doesn't heat the coffee as much, so it tastes better! The more common way is to put the main heating element in the base, so it does double-duty as a keep-warm heater. After the coffee is made, the thermostat cycles on and off, running the heating element momentarily at full power to keep the coffee warm! Care to guess which type I've studied the most?
One common feature in "deluxe" model coffeemakers is a timer. Before bed, you fill the reservoir with water and put fresh coffee in the basket. About the time your alarm goes off, the coffeemaker switches on, and the aroma helps you get moving. However, if the unit catches fire, it does so while you're in bed! The result: poor folks with the basic models could pull the plug when their coffeemakers started to smoke and stink, the result rarely worse than a scorched countertop. Heavy sleepers with the expensive models were more likely to experience a dangerous structural fire.
One interesting thing I learned: occasionally a manufacturer rolls over and gives up without a fight when they should have defended themselves. Another manufacturer (I've seen how they build their coffeemakers and they're one of my favorites) settled a case for eight figures. A fire had occurred and some children in the home had been killed and injured. However, the original fire investigator stated in his report that the coffeemaker was not even plugged in at the time of the fire! The TCO manufacturer confirmed this when they examined the unit years later, noting uniform soot on the plug! A sloppy insurance investigation had evidently incorrectly concluded the coffeemaker was at fault. At this point, there's no way to know for sure just what caused the fire, but it is clear that the wrong party paid up and took a severe hit in the public opinion area.
I have a couple of "pet peeves" in the lighting business.
The first of my pet peeves is incandescent light bulbs with brass bases. These bother me so much that, when I first set up my consulting business a few years ago, I was going to do a study on them out of my own pocket. Alas, possibly due to my recommendations to CPSC, I couldn't find any on the market when I went to buy them! I had investigated several alarming incidents for CPSC in which "Edison-base" light bulbs had erupted in a bright blue flash, sometimes throwing white-hot metal droplets. In each case, the same brand of imported brass-based bulb was installed in an aluminum screw-shell socket. I'd also personally had an aluminum-based candellabra bulb do the same thing when screwed into an old brass-based socket.
Then I helped out on a fire investigation in which a fire had mysteriously started on a floor. I noticed the socket of a desk light was missing the bulb, but half of the socket was eaten away, in the same familiar pattern I'd seen in the CPSC investigations. No doubt, the socket/bulb interface had erupted in a bright flash, and thrown out a few droplets of white-hot metal, hitting something flammable. Alas, by the time the case was brought to me, the site had been cleaned up and the evidence lost.
The second pet peeve is "protected" fluorescent lamp ballasts. The "protection" in these is usually a self-resetting thermostat. What a brilliant idea: when the magnet wire in a ballast begins to degrade, shorting adjacent turns and causing excess heat, switch it off, let it cool down a little, and then let it come back on! In one case I studied, the failing lamp evidently was in the off (cooling) phase when the office was closed for the holidays, but came back on shortly thereafter. It cycled for a couple of days, getting a little worse with each cycle, and finally caught fire. The damage was quite expensive.
My third pet peeve is some models of "high-intensity desk lamps," the kind which use a low-voltage halogen bulb, a transformer in the base, and a pair of uninsulated conductive rods which both support and power the bulb/reflector assembly. What nut approved these?!! Drop any metal object across the two conductors, and you have possible sparks and/or hot metal!
So if any of you fire investigators out there encounter any of these situations, you now know what to look for! And I'd certainly love a chance to look at what you find!
