Safe usage of gas

In this brochure contains useful information including various references to other sources of information relevant to your installation and its connection to the national grid. You will also find important telephone numbers for reporting emergencies or works around the gas receiving station.

If you have any questions about this brochure, contact the GTS Industry Desk or our Safety Department afdeling veiligheid. This brochure can be downloaded from our website.

View all frequently asked questions

FAQ Safe usage of gas

  • A supply pressure as shown in the first column is agreed with you (see table under; How high should the design pressure of the gas installation connection and the gas installation after the gas receiving station be?.

    The table shows the maximum pressure allowed in the pipeline in the event of an incident.

    You must ensure that the design pressure of your pipeline system is suitable for this MIP. If appliances are connected to this system which do not normally work if the gas pressure approaches the MIP (see 2nd column), then these appliances must be protected against this. This can be done by means of electric or mechanical safeguards against overpressure.

  • There is normally one supply gas pressure regulator in the gas receiving station/letdown station, equipped with safety devices to reduce the gas pressure to the set value of the gas outlet pressure and a second reserve gas pressure regulator which is identical. For higher capacities there are three gas pressure regulators (two supplying gas + a reserve). In the event of a fault in the supply gas pressure regulator or when maintenance work is being done, the reserve takes over the gas supply at a lower pressure. To give an indication, the pressure can drop 0,3 bar in a gas receiving station/letdown station equipped with two gas regulators in these circumstances. Where there are three gas regulators, in the worst case scenario the pressure can drop by about 0,6 bar. This can affect the settings of the low pressure monitoring system in your combustion installation. You are therefore recommended to set your low pressure monitoring system to a minimum of 0,4 to 0,7 bar (depending on the number of runs in the gas receiving station) lower than the settings of the gas receiving station,  taking account of the loss of pressure over the connecting pipelines.

  • You must be able to demonstrate that the installation has been designed, manufactured and inspected in accordance with the applicable legislation and regulations. You must be able to demonstrate that the installation has been maintained and inspected in accordance with the applicable legislation and regulations throughout its use.

  • New gas pipelines
    Gas pipelines designed for a pressure of >500mbar must be constructed in accordance with the Pressure Equipment Directive (see http://www.rijksoverheid.nl/ministeries/szw ). Under this Directive, the design of a gas pipeline must be checked by an organisation designated by the Ministry of Social Affairs and Employment (Notified Body, NoBo for short). Go to http://www.rijksoverheid.nl/ministeries/szwl and search for - Warenwetbesluit drukapparatuur -. An EU Declaration of Conformity for the product or combination of products must be drawn up by the manufacturer or assembler as specified in the Pressure Equipment Directive.

    Existing gas pipelines
    The gas pipelines must be subjected to a proper quality system. NEN 2078, annex K can be used for this. By 2011 the NEN 2078 was expired and succeeded by the EN 15001-1 and EN 15001-2 (Detailed functional requirements for commissioning, operation and maintenance).

  • New standard gas appliances
    Under the Gas Appliance Directive (GAD), new standard gas appliances, such as central heating boilers and hot air heating, are required to have a CE mark. For standard appliances, which have a CE mark, the installer must produce a report stating that the appliance has been set according to the manufacturer's settings. For standard appliances, or assemblies (cascade connections) being one combustion installation with a nominal capacity of >100 KW, which have a CE mark, a certified body must draw up a report stating that the appliance has been set according to the manufacturer's settings. The commissioning certificate must be in conformity with SCIOS (certification, inspection and maintenance body for combustion installations). For more information see: www.scios.nl.

    New special gas appliances
    For these appliances a complete manufacturing file must be prepared by the manufacturer and assessed by a certified body. The commissioning certificate must be in conformity with SCIOS. For more information see: www.scios.nl. The manufacturer or assembler of these appliances draws up an EU Certificate of Conformity.

    Maintenance of existing appliances
    Existing appliances should be maintained and inspected at the intervals specified by the manufacturer. Maintenance can also be carried out according to the SCIOS guideline. More information and a list of SCIOS-certified inspection and maintenance companies can be found on the organisation's website www.scios.nl.

    Inspection of existing appliances and pipelines
    Existing appliances and pipelines must be maintained and inspected at the intervals indicated by the manufacturer.

    The Decree on Emission Regulation Mid-sized Combustion Plants [BEMS] expired on 01-01-2013 and was replaced by the "2013 ACTIVITIES DECREE".
    What changes have been made with regard to combustion plants in the 2013 ACTIVITIES DECREE:
    The term ‘combustion plant’ is now the same as in the Industrial Emissions Directive (Combustion plant: any technical apparatus in which fuels are oxidised in order to use the heat thus generated).

    As a result, the following combustion plants are now also covered by the scope of the Activities decree:

    1. Plants in which the combustion gases are used solely to dry or treat products, such as brickworks, bakers’ ovens, cement ovens, plant used for roasting ores, drying hay and green fodder, asphalt mixing plants, pelletising plants, glass furnaces and so on.
    2. Combustion plants in which the heat is transferred to thermal oil, with the thermal oil acting as a medium for heat transport.
    3. Process ovens: combustion plants used primarily for purposes other than heating water or steam.
    4. Space heaters, used for heating (rooms).
    5. A new definition of ‘boiler plant’ has been added: combustion plant, consisting of a boiler in which fuel is burned primarily in order to generate power or transfer heat to water, steam or a combination of water and steam.
    6. Newly installed gas-fired boiler plants with a capacity of 400 kW or more must undergo an NOx test must take place within four weeks of commissioning. This requirement applies to all combustion plants with a capacity of 400 kW or more from 1 January 2017.
    7. The new Activity Regulations (art. 3.7 m) state that the test must be carried out by a firm holding a valid certificate issued by a body which is accredited by an accreditation body in accordance with the “Assessment Guidelines for the Performance of Maintenance and Inspections of Combustion Plants” which form part of the ‘Rules on the Certification of Inspection and Maintenance of Combustion Plants’ drawn up by the Netherlands Foundation for the Certification of Inspection and Maintenance of Boiler Plants (SCIOS).

    In other words: the firm performing the test must have an SCIOS certificate for the plant which is to be tested. Equivalence has been abolished.


    In addition, the emission requirements for combustion appliances using gaseous, liquid and solid fuel have been tightened and extended.

    Foreign firms wishing to conduct inspections in areas covered by SCIOS can apply to the Accreditation Council for equivalence.

    [1] Source:  http://www.infomil.nl/onderwerpen/integrale/activiteitenbesluit You can find more information in Dutch about the 2013 activities decree here.
    The Dutch text of the official publication can be found at: https://zoek.officielebekendmakingen.nl/stb-2012-558.html 
    Pay particular attention to points 6 and 7 which are essential, which was not the case in the BEMS.
    For information about maintenance and inspection of fuel pipelines, read the section headed What relevant legislation is there in this area.

  • If the gas equipment link is temporarily decommissioned at the request of the connected party for alteration, adjustment or repair of the gas equipment behind the gas transfer point, this alteration or repair must comply with the relevant legislation and regulations. This adjustment or repair must be carried out in a demonstrably integral manner. Integrity is demonstrated via a notified body under the terms of the Commodities Act Decree on Pressure Equipment or the user's inspection department.
    See also: “What action is taken when the gas receiving station (GRS) is decommissioned or commissioned.

  • After the transfer point, cathodic protection is your responsibility.

    Control measurements must be taken in accordance with EN 12954. The frequency of the measurements depends on a number of different factors but annual measurements generally suffice.

    A limited stream from the Gasunie network continues to be available.
    The Gasunie cathodic protection posts behind the transfer point are removed.

  • A summary of the relevant legislation relating to integrity of gas equipment link connections can be found at Legislation Industrial Installations. The Activities decree specifies that both appliances and fuel pipelines must be tested. The scope for fuel pipelines consists of two parts. The required frequency in this scope is once every four years. An extended test is also carried out once every eight years. The appliance scope is carried out according to the frequency specified in the decree. See:  www.infomil.nl/onderwerpen/klimaat-lucht/stookinstallaties/bem

    Varying or additional conditions may be made in the environmental permit.
    A summary with respect to gas receiving stations is given in the regulations based on ATEX
    Further sites about legislation are:

    overheidsloket.overheid.nl
    www.infomil.nl
    www.europa.eu

  • An overview of the applicable standards is given in "Normen industriële installaties" and the "Overview of European standards and developments in standards which have been harmonised with the Pressure Equipment Directive".

    All Dutch standards can be ordered from the website of the Netherlands Standardisation Institute NEN www.nen.nl. On www.euronorm.net there is a great deal of information about legislation and standardisation.

    It provides an excellent summary of the European standards applicable to industrial gas installations.

  • On the website of the "Raad voor Accreditatie"* (www.rva.nl) you will find the organisations which are accredited for the relevant area.

    Search on the scopes:

    • Organisation country = Nederland
    • Search in contents of scopes = Drukapparatuur

    Note that not all organisations shown here perform inspections.

    * The "Raad voor Accreditatie" has been assigned under the "Wet aanwijzing nationale accreditatie-instantie (Wanai)" as national accreditation authority.

  • Your gas installation connection and gas installation must not constitute a hazard that could disrupt the operation of the national gas transmission network. To comply with section 2.9 of the Connection Conditions for Gas - NNO, you must take the following measures in your own gas installation connection. Failure to comply with this condition means that section 2.10 of the Connection Conditions for Gas - NNO apply. Protective measures are taken in the gas receiving station to protect the connected party's gas installation from too high gas pressure.

  • The design pressure must always be higher than the pressure of the gas supplied to you by Gas Transport Services. This is necessary because the regulated pressure is protected in the gas receiving station by a blow-off safety feature and 1 or 2 cut-out safety features. A margin is necessary to ensure that this is set up to operate safely.

    The table below gives the relation between supply and design pressure (MOP; maximum operating pressure and the maximum outlet pressure (MIP; maximum incidental pressure) of the GOS.

    Gas receiving station - Gasunie Possible highest setting of safety features in the GOS
    Outlet pressure (Pu) Normal supply pressure MIP (max. incidental pressure outlet side)
    bar bar
    0,5 t/m2,0 4,4
    > 2,0 t/m4,0 6,6
    > 4,0 t/m8,0 11,0
    > 8,0 t/m13,6 17,6
    > 13,6 t/m15,0 22
    > 15,0 t/m17,0 22
    > 17,0 t/m22,5 27,5
    > 22,5 t/m38,0 44
    40 (open pijp) 46 (1.15 X MOP)
    80 (open pijp) 92 (1.15 X MOP)

    The minimum design pressure of your gas system depends on the highest setting (MIP) of the safety features in the gas receiving station  and on the chosen design code/standard for your system. Based on these data, a notified body (NoBo) must determine what the design pressure of your gas system should be.