Implementation of COMAH heralds integrated approach to people and environment

COMAH (the Control of Major Accident Hazard Regulations 1990), set to come into effect on 1 April 1999, represents a major step forward in integrating control of safety and environmental risks at potentially hazardous industrial sites in the UK according to Alan Meale, Environment Minister with special responsibility for health and safety.


COMAH implements the Seveso II European Union Directive which replaces the original Seveso Directive on the control of major industrial accident hazards, proposed following the accidental production and release of a dioxin, an unwanted by-product of a runaway chemical reaction, in Seveso, Italy in 1976.

The Control of Industrial Major Hazard Regulations 1984, or CIMAH, represented implementation of Seveso I in the UK, and are revoked by COMAH. While COMAH continues the general principles of CIMAH, namely to identify, prevent and mitigate major accidents involving dangerous substances, there exist a number of differences.

Firstly, COMAH demands that all sites have a Major Accident Prevention Policy setting out specific measures for preventing major accidents, and safety reports will be required to demonstrate safety rather than simply describe safety measures.

COMAH also proposes greater use of generic categories such as ‘toxic’ or ‘highly flammable’ to reduce the number of named substances and allow new chemicals to be categorised almost immediately when assessed against specific criteria. Further, the proposed legislation introduces a new category of substances, that of ‘dangerous to the environment’, whereby organisations are required to consider not just the impact on people, but on the environment in general.

As Meale highlighted: “An important difference between COMAH and the CIMAH Regulations they replace is the increased emphasis on controlling the risks to both people and the environment through sound management. This will ensure that safety and environment matters are integrated into the routine of business and not simply dealt with as an add-on.”

Steve Humphrey, head of Process Industries Regulation at the Environment Agency, said: “The challenge is to work out the matrix of the most obvious and the most immediate impacts on the health of the people on the site or the immediate environment, but then to look at real impact on the environment from a much more global point of view. Firewater presents a clear example, because not only can it affect the receiving sewage treatment works if it goes there, but now, because much more of the sludge is used in terms of land re-use for its nitrogen content, or is incinerated, we then have to look at a completely different set of risk scenarios for when the material is released into the environment.”

COMAH will be enforced by a new ‘Competent Authority’, comprising the Health and Safety Executive, the Environment Agency and the Scottish Environmental Protection Agency working together to perform key functions and to ensure industry is regulated properly with the minimum of duplication.

On the subject of the charging regime to be introduced as part of COMAH, Meale referred to the informal industry liaison forum set up to discuss the operation of the financial and administrative arrangements, before adding: “It cannot be right that there are major industries around which risk the safety of our environment and people, and that the cost of that should be borne by the individual taxpayer. We, as government, will rule nothing in or out of the consultation process, but I think there is a recognition in industry, particularly in the larger, more hazardous industries, that they have to play a part.”

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