Safety requirements for chemical piping
Companies must ensure that their chemical piping is operating reliably and that it is used safely. The requirements for piping are included in the legislation concerning chemical safety and pressure equipment, and these requirements apply to the design, manufacture, positioning and use of piping.
The buyer and manufacturer must agree in writing upon the responsibilities regarding the piping delivery and upon the technical information to be delivered to the manufacturer. This information is needed for piping classification and risk assessment.
The classification of chemical piping is based on the contents, pressure and diameter of the piping. The category determines the applicable conformity assessment procedure, i.e. module. According to the statutes on chemicals, at least category I module must be applied for the assessment of all piping containing dangerous chemicals.
The manufacturer is responsible for the following:
- piping design
- manufacturing
- risk assessment
- preparation of technical documents and operating instructions
- CE marking of the piping
- drawing up the declaration of conformity
- delivering the documents to the buyer in accordance with the agreement.
Concerning the implementation of technical details, harmonised EN and national standards for both metal and plastic piping are available.
The buyer of piping is responsible for the following:
- safe use
- operation training for the employees
- preventive maintenance
- maintenance
- inspections.
For piping in PED categories II to III, an inspection body must assess the conformity. An inspection body must also perform the in-service inspection of the piping at the request of the buyer.
Stages of the chemical piping life cycle
- Specify, in writing, the responsible manufacturer, scope of supply and technical specification of the piping.
- Agree upon the documents to be delivered and the person performing the risk assessment.
- Determine the contents, pressure and diameter of the piping.
- Classify the piping on the basis of the pressure equipment regulations.
- At least category I level must be applied for all chemical piping.
- Determine the module to be used in design and manufacturing.
- An inspection body must be involved in assessing category II and III modules.
•Assess the risks of the piping.
•Take account of any specific requirements, such as location, protection, equipment and safety devices.
•Design the piping to comply with the requirements, use standards.
•Ensure the qualifications of the welders and the suitability of the methods used.
•Prepare the technical documentation to provide the basis for manufacturing.
•Use construction methods that comply with the requirements, use harmonised standards.
•Take account of any needs for change during the manufacturing and installation, remember to update the documentation as necessary.
•Perform the required inspections.
•Perform the final inspection on the piping – inspection of technical documents, pressure test and inspection of safety devices.
•Mark the contents and flow direction to the piping.
•Affix the CE marking to the piping if the piping falls within PED categories I to III under the pressure equipment legislation.
•Draw up the declaration of conformity.
•Compile the design and manufacturing documents into a chemical piping record.
•Compile the operating instructions and supplement the instructions as necessary.
•Prepare a periodic inspection and preventive maintenance plan for the piping.
•Do not forget personnel training.
•Use and maintain in accordance with the instructions and plans.
•Perform any necessary repair and alteration work in compliance with the pressure equipment regulations.
•Attach the documents to the chemical piping record, do not forget the declaration of conformity.
•Make sure that the piping to be decommissioned is no longer connected to any piping that is in use.
•Make sure that the piping is completely empty and cleaned, and that any incorrect markings are removed.
•Decommission the unused piping.
See also
Safety requirements for chemical piping (in Finnish)
Safety of chemical piping, summary of the guide (pdf, 515 kt, in Finnish)
