Detection of Tungsten Hexafluoride

I'll be doing some work (as a software engineer) with a vacuum process chamber that consumes various nasty gases. There are numerous safeguards in the system, but as a cautious type, I decided to read the MSDS of the chemicals involved. The one that makes me the most nervous is tungsten hexafluoride; one mole apparently reacts with water to form 6 moles of HF, which I distantly remember from chemistry class as being bad news. Being largely composed of water, I find this troubling. If there were failures in the multiple safeguards and a leak did somehow occur, how could it be detected?




$\ce{WF6}$ is not an uncommon gas used in industrial manufacturing of semi-conductors. Commercial gas detectors are readily available, and will detect $\ce{WF6}$ down to low ppm range, which is about an order of magnitude less than the $\mathrm{LC}\_{50}$ for rats, apparently.


You could google tungsten hexafluoride detector, but some examples include (no affiliation or endorsement):


* <http://www.newcosmos-europe.com/gas-by-name/144-tungsten-hexafluoride-detection.html>
* <http://www.toxicgasdetection.co.uk/gas/?gas=Tungsten%20hexafluoride&search=Tungsten%20hexafluoride&form=gas&id=416>
* <https://www.gas-find.com/hexafluorure-de-tungstene.html>


The most common type of detector is a diffusion monitor with electrochemical sensor.
Some sensors actually use conversion of $\ce{WF6}$ to $\ce{HF}$, and then detect the $\ce{HF}$. Commercial $\ce{HF}$ detectors at low ppm range are also common.


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