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GRP Pipe systems specialists

​The quality and thus reliability of GRP (Glass-fibre Reinforced Plastic ) pipe systems is based on their design, production, assembly and maintenance. Therefore, end users, manufacturers, contractors, consultancies and other organizations need to ensure relevant competences of personnel during all stages, but especially related to connecting all pipes and other parts into one big GRP pipe system.

DNV has, in close cooperation with renowned stakeholders, set competence profiles for professionals working on GRP pipe systems. The certification of the professional competence requirements are in accordance with the ISO 14692, as determined by the DNV Committee and incorporated in the end terms. The DNV Certification Committee for GRP accommodates the major global end users, manufacturers, contractors and consultants for GRP pipes in developing and maintaining globally acceptable personnel competence standards and pragmatic but strict certification rules for the currently established competence profiles for field specialist in GRP pipe systems: 

A Bonder is a skilled worker, specialized in jointing GRP pipes, who’s competences are certified related to one or more different types of joints (e.g. laminated joints , adhesive joints, threaded joints, “O”-rings, locking keys etc.)

Spool builder
A spool builder is certified bonder and additionally certified for assembling the GRP spools and fabricate GRP (mitered) Tee’s and mitered Elbows.

Pipe fitter
A Pipe fitter is certified to lay out, assemble, fabricate, maintain and repair piping systems.

A certified supervisor monitors and takes responsibility for the execution of the work done by the bonders, spool builders and pipe fitters.

The certified inspector independently monitors the installation of the GRP piping systems. He controls and verifies that bonders, spool builders, pipe fitters, supervisors and other personnel have performed in compliance with the job specs.

The candidates shall be trained by (local) training institutes in relation to the competence requirements, up to the desired certification level. DNV can facilitate trainers and training institutes through “workshops for GRP-examination”.

Overall certification process
The certification schemes may include training prerequisites as an entry requirement/application requirement for the examination phase.  During the examination phase, a certification candidate will have to demonstrate his/her knowledge, skills and performance in a theoretical and practical exam. The exam pieces will be tested according specific DNV-criteria. More information about the personnel certification of GRP can be found on this page. 

General test criteria for exam pieces

  • All joints/connections have to pass a hydro test.
  • Test spools shall pass a hydro test, using a three times higher pressure then the design pressure for over one hour.
  • For Hi-pressure, specific test protocols are applicable

The execution of the tests will be supervised by a DNV authorized examiner whilst using control equipment according to the DNV spec. 

Examination details
DNV enforces and monitors the quality and independency of the by DNV licensed examination organization GRPcenter and authorized examiners.  The examinations shall be supervised by a DNV authorized examiner whilst using control equipment according to the DNV spec.  During the theoretical and practical exams, the DNV examination regulations are applicable.

For Bonder: 

  • Theoretical test: consist of 35 multiple-choice questions. Available time: 60 minutes.
  • Practical test: the candidate has to produce a joint in accordance with the desired certification level and range.

For spool builder:

  • Theoretical test: Consist of 35 multiple questions + 2 cases
  • Practical test: the candidate
    • Shall produce a joint in accordance with the desired certification level and range and includes making calculations based on manufacturing literature and listing the tools needed.
    • Shall execute a hydro test under supervision
    • Shall make a report about the own exam spool
    • Shall make a report about a prepared exam spool

For pipe fitter:

  • Theoretical test: 13 multiple questions and 2 extra cases in addition to the examination for a spool builder
  • Practical test: the candidate has to produce a joint in accordance with the desired certification level and range and includes making calculations based on manufacturing literature and listing the tools needed. In addition, the candidate has shall calculate and perform a hydro test.

Examination and test facilities 
DNV has licensed the independent examination organization GRPcenter to organize certification exams and test and has authorized local examiners to supervise these examinations and tests. Although the exams and tests are strictly independent from any training institute, they can be efficiently organized and scheduled in cooperation with the local training institutes.

Certification decision
All exam and test results will be assessed by DNV per candidate preceding the certification decision by the Manager Personnel Certification of DNV. When a positive certification decision is taken, a DNV Competence Certificate will be issued to the certificate holder. 

DNV Certificate of Competence
The DNV certificate of competence for GRP field specialists will state the following essential information:

  • Name, initials and picture of the certificate holder,
  • Date of certification and expiry date,
  • Place of the exam,
  • Eventually specific norms or classes,
  • Range of certification (i.e.)
    • Diameter of the GRP pipe by test and certified diameter range
    • Design pressure and certified range
    • Manufacturers rules/specification if applicable
    • Other information “if applicable”
    • DNV Certification rules

All certificates of competence for GRP field specialists have a validity period of two year. Each six months, both the certificate holders and the employer/contractor shall validate the work experience of the certificate holder within his certification range. At the end of the two years validity period, the certificate holder has to take and pass the recertification exam, conditions related  to the initial exam.

All certificate holders are expected to perform in compliance with their certified competences and certification conditions. Complaints received by DNV  addressing incompetence’s by the certificate holder, may lead to sanctions  for the certificate holder.

The DNV Certification committee and examination committee
The DNV certification committee for GRP, involving renowned stakeholders from all over the world, advices DNV on the maintenance of the competence profiles and certification rules, taking into account market developments, technological development, products and assembly developments and their own valuable experiences. The DNV examination committee for GRP will approve and monitor the examination methods and evaluate the validity of the exams through statistical analyses.



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