There's no set temperature, that I know of. However, as others have stated, the industry standard is about 165 degrees. I can give some other figures, as well. For example,t eh little coffee cup hotplates you can buy to keep your coffee warm run at about 120 degrees, max, which is considered drinkable temperature. FOr serving temperatures, how anout this from Bunn (
http://www.bunnomatic.com/pages/coffeebasics/cb6holding.html)
"Ideal serving temperature: 155ºF to 175ºF (70ºC to 80ºC)
Many of the volatile aromatics in coffee have boiling points above 150ºF (65ºC). They simply are not perceived when coffee is served at lower temperatures."
Or from
http://housewares.about.com/od/majorappliances/p/lglcrm1240micro.htm:
"Coffee Maker Features:
The coffee maker has 760 watts of power, a replacable carafe, an automatic timer with auto shut-off, coffee strength feature, and three temperature settings: High: 179F degrees; Medium 165F degrees; and, Low 147F degrees - so you can choose your preference of serving temperature."
Notice all are ten degrees or more below McDonald's serving temperature.
What you're telling me, here (and correct me if I'm wrong), is that the customer should expect any coffee served them to be hot enough to cause third degree burns? That's a bit extreme.
Claus, you're falling into an Either-Or fallacy here. This is not a clear-cut her fault-or-their fault issue. Was she negligent for putitng the coffee in her lap? Yes, she was. However, McDonald's served their coffee at a much higher level than the industry standard, had had many issues arise before of injury due to thier coffee, and had consistantly refused to either changed thier practice or provide any sort of warning or notice.
It is not reasonable to expect third degree burns from coffee. That's the issue here (as I see it). If she had opened the coffee cup and poured it over her head, McDonald's shoudl still be responsible for part of the incident, due to the extreme temperature.
Try this from
http://www.vanfirm.com/mcdonalds-coffee-lawsuit.htm:
"At that point, Mr. Goens and the other jurors knew only the basic facts: that two years earlier, Stella Liebeck had bought a 49-cent cup of coffee at the drive-in window of an Albuquerque McDonald's, and while removing the lid to add cream and sugar had spilled it, causing third-degree burns of the groin, inner thighs and buttocks. Her suit, filed in state court in Albuquerque, claimed the coffee was "defective" because it was so hot.
What the jury didn't realize initially was the severity of her burns. Told during the trial of Mrs. Liebeck's seven days in the hospital and her skin grafts, and shown gruesome photographs, jurors began taking the matter more seriously. "It made me come home and tell my wife and daughters don't drink coffee in the car, at least not hot," says juror Jack Elliott.
Even more eye-opening was the revelation that McDonald's had seen such injuries many times before. Company documents showed that in the past decade McDonald's had received at least 700 reports of coffee burns ranging from mild to third degree, and had settled claims arising from scalding injuries for more than $500,000. "
Also from the same source:
"The trial lasted seven sometimes mind-numbing days. Experts dueled over the temperature at which coffee causes burns. A scientist testifying for McDonald's argued that any coffee hotter than 130 degrees could produce third-degree burns, so it didn't matter whether Mc Donald's coffee was hotter. But a doctor testifying on behalf of Mrs. Liebeck argued that lowering the serving temperature to about 160 degrees could make a big difference, because it takes less than three seconds to produce a third-degree burn at 190 degrees, about 12 to 15 seconds at 180 degrees and about 20 seconds at 160 degrees. "
3 seconds for third degree, compared to 12 with a 10 degree drop. That's likely enough time that the spilled coffee would cool before reaching third degree burns. I don't think there's a set standard for coffee temperature, but when it can cause severe burns in three second, it needs a warning.