# The Environmental Protection (Prescribed Processes and Substances) Regulations 1991, 

Extent: E+W+S

Firing heavy clay goods or refractory material in a kiln where a reducing atmosphere is used for a purpose other than coloration.

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Source: https://www.legislation.gov.uk/uksi/1991/472/schedule/1/part/3/crossheading/section-36-ceramic-production-1 (the official version)
Page: https://openlegislation.uk/environmental-protection-prescribed-processes-and-substances-regulations-1991/schedule-1/part-3/crossheading-section-36-ceramic-production-1
Contains public sector information licensed under the Open Government Licence v3.0. Source: legislation.gov.uk, The National Archives.