The refrigerant to be used is R134a (HFC 134a). This is in line with my Department's policy for all major construction projects. The Department's policy is for natural ventilation for buildings whenever possible and only to install cooling systems where absolutely necessary. Where cooling cannot be avoided, designers are required to investigate systems which minimise environmental impact in terms of ozone depletion and global warming, using refrigerants with a zero ozone depletion potential (ODP) such as R134a and R66.
The Design stage of the 50 Queen Anne's Gate refurbishment has been assessed under BREEAM for Offices 2004 and has achieved a rating of "Excellent". BREAAM is a rating method to assess and improve the environmental performance of buildings.