SI 2015/399 The Pressure Equipment (Amendment) Regulations 2015 (link)
These Regulations amend the Pressure Equipment Regulations 1999 (link) in order to implement Article 13 of the new EU Pressure Equipment Directive (2014/68/EU), which aligns hazard classifications for substances and mixtures with Regulation 1272/2008/EC on the Classification, Labelling and Packaging of Substances and Mixtures.
Regulation 3 replaces the definition of “fluid in Group 1” in the 1999 Regulations and thereby implements the new hazard classifications in the 2014 Directive. Regulation 4 amends the definition of “fluid in Group 2” consequentially.
Source: HMSO