Sprinkler Head

<sigh>

What sort of sprinkler head?

Try narrowing that down from the 1000's

Then try narrowing down what part of that particular head you are interested in.

Frankly, I don't know we have that much of sprinkler heads. What I mention is about the general sprinkler head used by fire water (I mean water), the most popular type, the temperature is about 65degC. to activate and the water pressure is about 10bar.

Why I ask this because some people tell me that the liquid inside is liquid mecury and I start thinking that this should be poison if there are 40 heads opens at the same time.

This may involve TonyS since he may hits me by aksing that why I did not ask it at the first place. My mistake. LOL

This is what Wikipedia has

http://en.wikipedia.org/wiki/Fire_sprinkler

Have tried this before you posted it but the site does not mention about the kind of liquid.

You wouldn't be lucky enough to have a brand or a model #?

I was told it is an alcohol base with amounts of glycol (or possibly glycerol?) and a dye to indicate ranges. Then again they could have been fibbing.

Possibly it is correct since my HSE coleague told me it was alcohol. She was told be other, too.

It won't be mercury (Hg). One can see through it.

There speaks a man who has blown 1 or 2 thermometers

I thought they had wax in.
When the wax melts, the head opens and swoosh
Del

There are genuine mercury thermometers, but most straight thermometers contain a red alcohol-based liquid (easier to see, nonpoisonous). If the liquid expands enough to completely fill the tube, the tube breaks from hydrostatic expansion.

Think of a sprinkler actuator as a "short thermometer" that is designed to break at 65°C, thereby opening the sprinkler head.