Dear Sir,

Our Company is in Hong Kong. Some of the Copper equipment in our company
has been contaminate with H2S( Hydrogen Sulphur). The Copper Sulphur
that change the copper colour into Black and begin to corrosion.  The
Air sampling shown the level of H2S is about 25 micro g/m3
I would be grateful if you know the answer of the following questions or
give us some suggestion for our company.
1)  Is the 25 micro g/m3  H2S save  to prevent the copper to continue
corrosion ?
2) What is the save H2S level to prevent copper corrosion ?
3) What action we need to take to prevent continuses copper corrsion ?


Thank you for your help.
I will be looking forward to hear from you in the near future (E mail
address :   [log in to unmask])

Mr wong Kwok Fai