Nitrogen Gas Detector

For what purpose? How critical is the application?

It's purpose is to detect leak on distribution transformers .

Just how could that be made to work?

Ahah! So now, "absence of oxygen", as suggested in #4, #5 and #8⇓, is not the preferred technique.

• A simple pressure gauge and a set of readings of it over time will detect a leak.
• A mixture of common washing-up liquid in water, squirted onto the suspect area, will detect the location of the leak, which will become apparent as a cluster of bubbles.

Bubble test is a great idea, but if there is a nitrogen leak you could well be dead before you see the bubbles - nitrogen is the silent killer - no gag reflex.

How much Nitrogen do you think could quickly leak from this transformer, and, how much do you think you would need to leak to significantly affect the percentage of Oxygen in the air?

I have been in a small room (about 12' x 12' x 8') which had recently (a few minutes before) had about half an inch of liquid nitrogen boiling on the floor. The delivery driver who was filling the dewar, had miscalculated the amount required, and, actually paddled through the stuff to turn off the feed. I suspect that this was not an uncommon event because he seemed to be totally unphased (his boots also looked as though they were designed to withstand the effects of the LN₂).

At what concentration?

What other gases are present?

http://www.starkinstrument.com/e_productshow/?141-Portable-nitrogen-gas-detector-141.html

Since air is 78 percent nitrogen, it'll be hard finding any place you won't find some nitrogen.

Nitrogen is an asphyxiant. So, any animal that falls unconscious and dies would be a <...good nitrogen gas detector...>.

"Absence of oxygen" is easier to detect, and there is equipment available commercially that does this readily.

Get a piece of paper and write in bold letters:-

"YEP: NITROGEN IS HERE"

Put it in your pocket and carry it wherever you go; any time your not sure just take it out: it will always detect nitrogen.

Don't bother testing for nitrogen, but test for oxygen %. Drager are great for personal portable gas detection. I seem to remember the Drager 3500, but they would know the best for your needs.

You can also check about the Dräger Pac® 8000 and Dräger X-pid® 8500.