Yes there is ISO and AFNOR

Hi Emeka, the International Finance Corporation of the World Bank Group have a general Environmental, Health, and Safety (EHS) Guidelines that are technical reference documents with general and industry-specific examples of Good International Industry Practice. There you can find a section with wastewater and ambient water quality with their suggested industrial discharge standard limits.

Here is the link in case yo can find them useful.

http://www.ifc.org/wps/wcm/connect/topics_ext_content/ifc_external_corporate_site/sustainability-at-ifc/policies-standards/ehs-guidelines

1.Global Effluent Guidelines-http://www.levistrauss.com/wp-content/uploads/2014/01/Global-Effluent-Guidelines.pdf

2. ISO- https://www.iso.org/news/2015/03/Ref1945.html or https://www.iso.org/files/live/sites/isoorg/files/archive/pdf/en/iso_and_water.pdf

3. Industrial effluent guidelines US EPA- https://www.epa.gov/eg/industrial-effluent-guidelines

4.EHS guidelines -http://www.ifc.org/wps/wcm/connect/topics_ext_content/ifc_external_corporate_site/sustainability-at-ifc/policies-standards/ehs-guidelines

I go with Dr K N Sheth

As stated by Sheth sir

Dr Sheth has given all codal standard of Global authorities.

Dr Sheth has given all Global standards