# The Coal Mines (Cardox and Hydrox) Regulations 1956, Regulation 20


Where a round of shells is to be fired the person about to fire them shall ensure that they are connected in series.

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Source: https://www.legislation.gov.uk/uksi/1956/1942/regulation/20 (the official version)
Page: https://openlegislation.uk/coal-mines-cardox-and-hydrox-regulations-1956/regulation-20
Contains public sector information licensed under the Open Government Licence v3.0. Source: legislation.gov.uk, The National Archives.