Smoke-free Premises etc. (Wales) Regulations 2007
From Mental Health Law Online
Regulation 3 provides for a permanent exemption to the anti-smoking Health Act 2006, for "designated rooms for use by those aged 18 years or more" in a "mental health unit which provides residential accommodation for patients".
See also
Resources
Smoke-free Premises etc. (Wales) Regulations 2007 on Statute Law Database