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CDOIF
Chemical and Downstream Oil
Industries Forum
CDOIF is a collaborative venture formed to agree strategic areas for
joint industry / trade union / regulator action aimed at delivering
health, safety and environmental improvements with cross-sector
benefits.
Unmitigated risk
The aggregated risk from credible scenarios, before any mitigation measures are
employed, refer to section 4.3 ‘Aggregating Risk and Risk Frequencies’. This is the risk
(consequence and frequency) associated with all credible scenarios given failure of
prevention layers, escalation and no mitigation.
Mitigated risk
The level of risk that remains from all credible scenarios once existing protection layers
(mitigation and/or prevention measures) are employed, refer to section 4.3 ‘Aggregating
Risk and Risk Frequencies’.
Further risk reduction measures
Further risk reduction measures which could be employed to reduce the risk further to
TifALARP or Broadly Acceptable. An ALARP demonstration, which might include Cost
Benefit Analysis, may be required to further justify a claim of TifALARP.
4.2
MATTE potential matrix
The sources, or more importantly the substances which could give rise to a MATTE
should be screened for each relevant receptor to determine their potential.
In order to screen for potential credible MATTE scenarios, it is important to understand
the following:
x
The types or groups of substances present on the site which could cause a MATTE
x
The receptor itself, and how it could be polluted (or otherwise harmed) to the extent
of causing a MATTE
x
The site specific scenarios that could cause the receptor to be polluted (or otherwise
harmed) to the extent of causing a MATTE
4.2.1
Grouping and compartmentalisation
To simplify the process of risk assessment, duty holders may consider grouping different
product categories (or substances with similar risk phrases) which have a similar nature,
and can damage the receptor in a similar way, for example:
x
Petroleum products
x
Dense non-aqueous phase liquid
Grouping of similar products can also be considered based on geographical location, for
example, all products stored in a tank farm(s) have similar properties and all have the
potential to pollute a nearby receptor(s).
On this basis it may not be necessary for sites to complete risk assessments for
individual tanks and individual products but instead to group similar substances and
‘compartments’ of tanks within the site boundary.
Guideline – Environmental Risk Tolerability for COMAH Establishments v1.0
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