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Safety and environmental standards for fuel storage sites
Final report
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b A joint with a plastic waterstop and stainless steel cover plate designed to ensure
product and fire resistance to BS 476 – This meets current good practice and no
upgrade would be required. It is unlikely to have a significant rate of liquid egress
from joint although loss of integrity of the plastic waterstop may eventually occur after
protracted heat exposure.
c A joint with no waterstop but with a stainless steel cover plate, with product and fire-
resistant sealants designed to ensure fire resistance to BS 476 – This joint may be
considered to be fire resistant and would be considered impermeable (liquid tight)
whilst the product-resistant sealant remains in good condition. Leakage rate through
movement of the joint would also be expected to increase with sealant ageing and
hence frequent sealant inspection and replacement routines shall be in place to ensure
sealants remain in a good condition.
d A joint with no waterstop, no cover plate but with product- and fire-resistant sealant –
This joint only provides limited fire resistance and is impermeable only when the product-
resistant sealant remains in good condition. Leakage rate through movement of the
joint would be expected to increase with sealant ageing. As a minimum, this should be
upgraded with a stainless steel cover plate and inspection and replacement routines
shall be in place to ensure sealants remain in good condition.
e A joint with product-resistant sealant but no waterstop, no stainless steel cover plate and
no fire-resistant sealants – This joint will be impermeable whilst the sealant remains in
good condition but is not fire-resistant, and would be expected to leak rapidly following
a fire. Leakage rates through movement of the joint would be expected to increase with
sealant ageing. As a minimum, this joint should be upgraded with a stainless steel cover
plate and fire-resistant sealants. In addition, inspection and replacement routines shall be
in place to ensure sealants remain in good condition.
Table 4
The potential for bund failure
Bund Wall Expansion and Construction Joints
Text
para
Waterstops S/S cover
plates
Fire-/product-
resistant
sealants
Acceptable standard Required
upgrade
a
Stainless steel
None
Yes
Acceptable and good
practice for existing plant
Best practice for new build
None required
b Plastic
Yes
Yes
Acceptable and good
practice
None required
c
None
Yes
Yes
Acceptable and good
practice for fire resistance
and for existing bunds only
acceptable for minimising
leakage provided an
adequate inspection and
maintenance regime was in
place (see paragraph 213)
None required for
fire resistance
Upgrade for bund
integrity dependent
on extent of tertiary
containment
d None
None
Yes
Upgrade required and
inspection and maintenance
regime
Install S/S cover
plates to achieve c
e
None
None
None
Upgrade required and
inspection and maintenance
regime
Install S/S cover
plates and fire
resistance to
achieve c