NEN NEN 3650-1 PDF

This standard specifies safety requirements concerning safety aspects for people, the environment and property, relating to the design, installation, operation and abandonment of pipeline systems.

The requirements relate to onshore pipeline systems for transport of substances by land, and apply to newly built systems and to the modification of existing systems.

Modification of existing systems means:

— replacement of pipeline parts/elements in the same route;

— diversions of pipeline sections/pipeline elements in a different route, as a result of land use developments and building work of third parties;

— repair/replacement of pipeline sections/elements within the operation of the pipeline system according to Clause 10 of this standard.

All work involving design, installation, operation and abandonment of operations shall be carried out by qualified and competent persons. Application of a quality management system, in accordance with EN-ISO 9001 or NEN-EN-IS0 14001, is strongly recommended.

This standard is applicable to Group I and Group II pipeline systems (see Figure 1):

a) The function of Group I pipeline systems is to transport intrinsically hazardous substances (see A.2.1). For Group I the entire pipeline system as a whole shall comply with the requirements of the standard. Pipelines to transport hot water according to A.2.4 shall also, unless otherwise indicated in the text of the standard, meet the requirements for Group I.

b) The function of Group II pipeline systems (see A.2.2) is to transport substances other than in a). For Group II, the application of the standard is limited to pipelines in or near important public works and pipelines located in groundwater protection areas.

NOTE 1 Pipeline systems consist of pipelines and stations. The pipeline can be a transportation pipeline, a distribution pipeline, as well as a collector pipeline. No distinction is made between them in the standard.

NOTE 2 This standard does not apply to stations and other pipelines or pipeline sections belonging to a Group II system that do not meet the condition relating to position under b).

This standard is also applicable for existing pipelines or systems with regard to:

— operation of Group I and Group II pipeline systems;

— modification of design conditions (including without limitation temperature, pressure, fluid, external loads).

This standard contains no requirements for:

— pipework of industrial installations, falling under the scope of the “Besluiten drukapparatuur” (Decrees on Pressure Vessels) and connecting to Group I systems, except for the ancillary equipment that forms part of the (pressure) limitation of the system. See Annex J.

Figure 1 shows a flow chart of the groups in relation to the standard(s). Figure 2 provides a schematic diagram of pipeline systems subject to the standard.

NEN 3656 contains the requirements for offshore transport of fluids.

Offshore pipelines are: all pipelines in or on the sea bottom of the continental shelf (regardless of whether they are in territorial waters), from the low-water line (LAT, Lowest Astronomical Tide) up to and including the connections to the installation as shown in figures 3 and 4.

NOTE 1 In this standard, the LAT is considered to be the “laagwaterlijn” (low-water line) as defined in the “Wet grenzen Nederlandse territoriale zee” (Act on the Boundaries of the Dutch Territorial Waters) of 9 January 1985 [4].

The landfall, the pipeline section between the LAT and the first valve after crossing the water-retaining structure shall comply with NEN 3650-1 and – within the safety zone of the crossing with the waterretaining structure – with NEN 3651 as shown in figure 1.

NOTE 2 In some cases, e.g. in the case of a “schaardijk” (dyke without floodplain) with rather steep underwater banks, the safety zone as defined in NEN 3651 can extend beyond the LAT.

NEN 3651 applies to that part of the offshore pipeline. NEN 3656 contains supplementary conditions and references for the landfall, including concerning the pressure control system and the containment system. The containment system of the offshore pipeline extends up to and includes the first valve after the crossing with the primary water-retaining structure.

Figure 3 shows a flowchart of the classification of offshore pipelines and the corresponding standards.