Chromatography Forum

Per the Agilent GC-ECD installation guide:

"Venting your ECD

The instrument in which the ECD is mounted must be placed where the ECD effluent can be vented. The ECD shall not be vented into the laboratory environment. A vent line to a fume hood is a convenient way to accomplish this. This precaution is taken to avoid radioactive contamination of the laboratory if an abnormal condition should occur. Agilent Technologies recommends a vent line running to a fume hood. The inside diameter should be 6 mm (1/4 inch) or greater to prevent back pressure which might cause noise in the ECD signal. With a line of this diameter, the length of the tubing is not critical."

How (or does) your laboratory follow this guideline? I have seen a Restek part where they have plumbed in what looks like a carbon trap http://www.restek.com/catalog/view/3174 - has anyone used this or something similar? Any thoughts on which is the more appropriate approach?

Never vented it... Nickel is not volatile.

6 mm ID flexible plastic tubing is the cheapest solution. ECD is non destructive detector, what goe's in - goe's out (eg. pesticides). We can't be sure that in abnormal situation analytes may react with Ni forming volatile Ni compounds.

If you work in a government agency, there may be specific rules in regards to radioisotope licensing and you should check with your safety director or whoever is responsible for the license.

Thanks for the replies so far. I think we'll end up venting through a carbon filter just to be safe (or at least to look safe).

FYI: for over the 10 years I ran that way wipe tests always came back negative

Yes, that Restek item is what we use- the worry is breathing your samples, not radioactivity. Same trap (should be) used on the inlet vent to catch solvent/sample vapors. By the way, if you're running GCMS, the vacuum pump exhaust also contains sample and oil traces, but I don't know of a good way to vent or trap them.

... By the way, if you're running GCMS, the vacuum pump exhaust also contains sample and oil traces, but I don't know of a good way to vent or trap them.

Dedicated charcoal trap on exhaust output of foreline pump or plastic tubing to ventillation duct.