Re: I have a question
In my understanding the limit of around 1 mg/liter is a very common limit at the point of entry to the sewer system. I do understand that the waste gets diluted very rapidly but that's not a factor incorporated in regulation. Regardless, this is a regulatory matter and whether I feel safe/ethical to continue to use ferricyanide for b&w bleach is a different issue. I think it's best to convince photographic chemical retail businesses to offer better alternatives. -- Ryuji Suzuki http://silvergrain.org From: Liam Lawless <lawless@bulldoghome.com> Subject: RE: I have a question Date: Sun, 21 Oct 2007 15:54:33 +0100 > Your figures re. pot. ferri. dilution are alarming, but at > what point should the concentration be 1 p.p.m. - when it > enters the drainage system, when it finally reached the > treatment facility, or somewhere in between? Won't it also > be diluted by waste water from other sources?
|