Appropriate measures with a view to protecting people and securing effective emergency response should be suitable for their purpose. They should also, taken together, enable the requirements of the Regulations to be met in the light of the circumstances on the installation, the stage in its life cycle, the nature of the hazard, the likelihood of it being realised and the potential consequences. In determining what is appropriate duty holders should take account of any specific requirements in the Regulations, the outcome of the assessments required by regulation 5 of these Regulations and regulation 3 of MHSWR, and the risks and the costs of various measures. Appropriate measures should be adequate to achieve the objectives set out in the regulation but would not require expenditure which is completely out of proportion to the risk their implementation avoids.
Source: Prevention of Fire and Explosion, and Emergency Response on Offshore Installations, Offshore Installations (Prevention of Fire and Explosion, and Emergency Response) Regulations 1995, Approved Code of Practice and guidance (UK HSE L65), Second Edition, 1997. Regulatory Guidance