Page 3 of the general approval no. Z-65.26-304 issued by the Building Inspection Authorities on June 26, 2001
I. SPECIAL
PROVISIONS
1
Subject of approval and field of application
1.1 The subject of this general approval is an overpressure leak detector of the type designation
"DLR-2/11." or "DLR-2/22". It works with inert gas, e.g. nitrogen, without a firmly installed
pressure tank and comprises a pressure absorber for controlling the alarm signal, display and
warning units as well as one connection each for the connecting pipe to the interstitial space of
the double-wall pipework and for feeding inert gas including a test pressure gauge. Leaks in the
walls of the interstitial space are registered by means of falls in pressure and then indicated
optically and acoustically (for the design of the leak display units see Appendix 1).
1.2
The leak detector "DLR-2/." may be connected the interstitial space of double-wall pipework laid
underground or overground in tempered rooms. The overall monitoring volume of all the double-
wall pipework connected must not exceed 10 m³ and the length of the pipework to be monitored
should not exceed 1200 m. The leak detector may only be connected to interstitial spaces of
double-wall pipework which is suitable for the storage of liquids hazardous to water. These are
interstitial spaces of double-wall pipework with proof of suitability awarded by the Building
Inspection Authorities.
1.3 This present general approval only serves to prove the functional safety of the subject of
approval in the sense of paragraph 1.1.
1.4 The general approval is granted regardless of testing or approval reservations of other legal
areas (e.g. 1
st
Directive to the device safety law - low-voltage guideline -, Law governing
electromagnetic compatibility of devices - EMVG guideline, 11
th
Directive to the device safety
law - explosion protection directive -).
1.5
This general approval of the building authorities means that the determination of suitability and
type approval of the subject of approval in terms of water regulations according to § 19 of the
Water Resources Law is not applicable.
2
Regulations applicable to the subject of approval
2.1 Composition
2.1.1 The subject of approval consists of the overpressure leak detector of the type "DLR-2/11" and
the type "DLR-2/22" including the parts listed in paragraph 1.1.
2.1.2 The proof of functional safety of the subject of approval in the meaning of paragraph 1.1 is
assured by the "Zulassungsgrundsätzen für doppelwandige Rohrleitungen (ZG-LAGR)"
("Principles for Approval for Leak Detection Devices for Double-wall Pipework"
) issued by the
German Institute for Constructional Engineering in August 1994.
2.2
Manufacture and marking
2.2.1 Manufacture
The leak detector shall be manufactured only in the applicant’s manufacturing shops. Its design,
dimensions and materials shall be in accordance with the specifications described in appendix 2
of the present general approval.
2.2.2 Marking
The manufacturer shall place the conformity mark on the leak detector, on the packing of the
leak detector or on the delivery note. The conformity mark shall be in accordance with the
relevant codes of the different states. Such marking is only valid if the conditions as per
paragraph 2.3 have been complied with. In addition, the leak detector shall be marked with the
following data:
Type designation
Approval number.
