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Safety and environmental standards for fuel storage sites
Final report
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126 Failure of an overfill protection system places reliance on the tank to avoid the uncontrolled
loss of primary containment of hazardous substances. The adoption of appropriate design
standards should ensure tank integrity and suitable overflow and venting mechanisms.
Throughout the life of the tank, integrity of primary containment should be maintained through a
process of periodic inspection, maintenance and repair.
127 In addition to a dutyholder’s responsibility to review their DSEAR (Dangerous Substances and
Explosive Atmospheres Regulations) risk assessment on a regular basis (eg using the guidance in
Area classification for installations handling flammable fluids
(EI 15)
18
) there are also requirements to
undertake reviews if there is reason to believe that the risk assessment is no longer valid or if there
has been a significant change. Hazard and risk analysis may be required to ascertain appropriate
risk reduction measures through additional layers of protection, as described in the guidance
provided for Recommendation 1. DSEAR risk assessments should reflect the findings of the
LOPA assessments (see Appendix 2). The need for a suitable and sufficient risk assessment is an
ongoing duty and, as further understanding of the mechanisms of the incident becomes available
and if additional specific guidance is produced, there may be a need for further reviews. DSEAR
risk assessments and the measures to control identified risks should, in addition to any sector or
industry-specific guidance, take account of the general guidance contained by the HSE Approved
Code of Practice (ACOP) L138
19
and where relevant the additional activity related DSEAR ACOPs:
Unloading petrol from road tankers
■
■
L133;
20
Design of plant equipment and workplaces
■
■
L134;
21
Storage of dangerous substances
■
■
L135;
22
Control and mitigation measures
■
■
L136;
23
and
Safe maintenance, repair and cleaning procedures
■
■
L137.
24
Reference should also be made to Appendix 2, paragraph 136 when considering the selection of
equipment and protective systems.
Part 3 Engineering against escalation
of loss of primary containment
MIIB Recommendation 11
Operators of Buncefield-type sites should review the classification of places within COMAH
sites where explosive atmospheres may occur and their selection of equipment and protective
systems (as required by the Dangerous Substances and Explosive Atmospheres Regulations
2002). This review should take into account the likelihood of undetected loss of containment
and the possible extent of an explosive atmosphere following such an undetected loss of
containment. Operators in the wider fuel and chemicals industries should also consider such a
review, to take account of events at Buncefield.
MIIB Recommendation 12
Following on from Recommendation 11, operators of Buncefield-type sites should evaluate the
siting and/or suitable protection of emergency response facilities such as firefighting pumps,
lagoons or manual emergency switches.