MCU14/0056 Response to SARA - Consulting Report

EN 858-1:2002 (E)

6.3.8 . Access covers

Access covers shall be in accordance with EN 124. Access covers with ventilation openings or those which can be
bolted down, are not permitted.

6.4 Structural stability

6.4.1. General

The separator system shall be designed to withstand the various loadings to which they are expected tobe
subjected (dead foads, live loads, soil pressure, water pressure) without detriment to their function and to the
environment and be protected against possible floating when empty.

The structural stability shall be based on national standards, transposing European Standards as available, or in
the absence of those is based on established national procedures and/or regulations for calculation or testing valid
in the place of use of separator.

NOTE Annex C lists documents which can be used in the framework of this clause and which will remain valid until
replaced by European Standards.

6.4.2 Separator systems made of unreinforced concrete, fibre-reinforced concrete, reinforced concrete
The crack width under design load shall not be greater than 0,20 mm for reinforced concrete.

When steel reinforcement is used, the concrete cover to the steel shall not be less than 20 mm on all sides for
prefabricated units, and not less than 30 mm on all sides for units built in-situ.

6.4.3 Separator systems made of glass fibre-reinforced plastics

Under the design load the laminate shall not be strained beyond 0,26 % or 1,3 Ed, whichever is smaller, where Ed
is the least strain determined from allowable loadings and the resin properties. The strain level shall be determined
by calculation. For general and locai stability the separator shall withstand the negative pressure tests in

accordance with EN 976-1:1997, clauses 5.8.2.2 and 5.8.3, where the separator system is installed at a minimum
depth of 650 mm and a maximum depth of 2000 mm.

6.5 Functional requirements /

6.5.1 General

The design of the separator system shall ensure that separated tight liquid cannot be discharged either accidentally
or in an uncontrolled way, e. g. by syphoning. The design shali also ensure that any separated and retained light
liquid is not disturbed.

Where automatic or manual oil skimming devices are fitted they shall not interfere with the separating effect.

6.5.2 Storage capacity for light liquids

For prefabricated separator systems, the separated light liquid storage capacity shall be at least ten times the
nominal size in litres where automatic closure devices are fitted, and at least fifteen times the nominal size in litres
where automatic closure devices are not fitted. These capacities shall be based on a light liquid density of
0,85 gfem?.

6.5.3 Automatic closure devices

Separator systems shall be provided with automatic closure devices.

NOTE Local authorities may allow the use of separator systems without automatic closure devices.

Automatic closure devices shall provide effective operation. The closure shall be operated by the accumulated light
liquid. Changes in flow rate shall be taken into consideration. ,

14 This is a licensed reproduction produced by SAI Global Ltd, an authorized distributor of British Standards