[dangerdoc]

Ammonia is still used as an industrial refrigerant, smelly stuff and quite dangerous when there is a spill.

[Red Badger]

It can be, but the smell drives people away quickly at concentrations well below danger, doc.................

http://www.goodway.com/hvac-blog/2009/08/ammonia-as-a-refrigerant-pros-and-cons/

[mountainlion]

Ammonia is still used as an industrial refrigerant, smelly stuff and quite dangerous when there is a spill.

I have worked in ammonia spills and it was not that bad. It is lighter than air and disperses quite well while R22 will sink and fill low spots. R22 had little effect on ozone but the manufactures wanted to make more money and get rid of the competitors of R22.