Statute Links:
Health and Safety At Work Act 1974 or Here
Management of Health and Safety at Work Regulations 1999
Personal Protective Equipment (EC Directive) Regulations 1992
Workplace (Health, Safety and Welfare) Regulations 1992

Links:
What is the maximum/minimum temperature in the workplace? - HSE
Temperature - London Hazards Centre Factsheet
Temperatures - Minimum and Maximum - HSE
Cold Stress - HSE
Heat Stress - HSE
Heat Stress: OSHA  Technical Manual

Downloads:
Cold - Working in Cold Weather - GMB (pdf)
Cold - Working in Cold Weather + Wind-chill Chart - Nuca.com (pdf)
Health Aspects of Work in Extreme Climates - Oil Industry International Exploration & Production Forum (pdf)
Heat - Feeling The Heat - GMB (pdf)
Heat Illness - HSE (pdf)
Heat Stress In The Workplace - HSE Information Sheet (pdf)
Keep Your Top On - Health Risks from Working in the Sun - HSE INDG147 (pdf)
Preventing Heat Stress at Work - WorkSafe British Columbia (pdf)
Prevention of Heat Illness in Mines - HSE (pdf)
Protecting Workers from Heat Stress - OSHA (pdf)
The development of a practical heat stress assessment methodology for use in UK industry - HSE Research
Safe Work in Confined Spaces / Approved Code of Practice - HSE (pdf)
Temperature at Work - Unison (pdf)
Workplace Health, Safety and Welfare - A short guide for managers -  HSE INDG244
Workplace Temperature - UK Parliament Briefing Paper (pdf)

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