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Comment by fijal | Hacker News Reader

This is the first time I see someone using Fahrenheit degrees outside of 0-150 range. Do Americans usually use F for stuff like material limits etc?

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Baking and candy making regularly specify temperatures in Fahrenheit up to 500 degrees in America. As for engineers, it largely depends on the policies of their employer. For most material properties, since the boiling point of water isn't terribly relevant, F works just as well as C (though obviously for any calculation beyond a simple threshold, you're going to want an absolute scale.)

I haven't come across temperatures that hot very often, but my assumption is that the average non-scientific US resident would use Fahrenheit for all temperatures, no matter what range, just because it is what they were most likely raised on.

Just out of curiosity, what would you suggest they use instead? Celsius? Kelvin?

Not the OP, but I'd say that for high temperatures it doesn't really matter if one uses Celsius or Kevin, and that's because 1 degree Celsius = 1 degree Kelvin. So, let's say that you have a reading of 800 Celsius, you just need to add ~ 270 to it if you want Kelvin. If I then get a second reading of 1200 Celsius I know for sure that it's 400 degrees higher compared to the first reading, no matter if I'm thinking Celsius or Kelvin.

For Fahrenheit things are not that straightforward

1200-800=400 in Fahrenheit too, you know :p

Really? Ok, I learned something new today :) Of course, if it wasn't obvious enough enough I'm from Europe where Fahrenheit has always confused us.

Yeah :) They're both linear. What confuses people is that degrees F are both smaller than degrees C and the 0-point is lower. They meet at -40 (so -40C == -40F) and from there, the F number changes faster than C, that's all.

We use it when talking about heat treating of carbon steel and other materials. Regular heat treat cycles between 900-1050 F. Some reference to higher temps when we talk to the natural gas people.

Yes. Non-science Americans use it for everything, in my experience, and can get confused by Celsius.

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