An article mentions the following:I think this move will spread to the whole of India. The way ammonia gas cylinders are handled in the small and medium scale industries leave a lot to be desired. It is an inherently safer option to replace ammonia used in refrigeration systems. On the same subject, I still observe a number of non chemical plants using chlorine for their water treatment systems. There are safer alternatives to chlorine and it is time that the industry takes a look at it.
"The West Bengal Pollution Control Board (PCB) has announced that ice or cold storage plants should switch from ammonia to HCFC 22 following a series of leakages. The ruling means that municipal corporations and municipalities should not give any further licence to any ice plant or cold storage in urban areas unless they submit written undertakings stating that they will use HCFC 22 methane as refrigerant gas instead of Ammonia.It’s claimed that ammonia gas leak from cold storages in the city and adjoining towns and other districts have previously affected thousands of people".
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