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What are high pressure piping systems?

The following are considered high pressure piping systems:

  • steam-system piping designed to operate at more than 15 p.s.i (pounds per square inch),

  • high-pressure and high-temperature fluids designed to operate at more than 250 degrees Fahrenheit and 30 p.s.i. gauge used for heating,

  • ammonia (717) refrigeration-system piping, and

  • bioprocess piping systems.

What licenses are required to install or fabricate high-pressure piping?

A business must first employ an individual who has a master pipefitter license. The business may then apply for a Minnesota high pressure piping contractor license. After the business has met these requirements, it may apply for a permit to install or fabricate high pressure piping. The business must also employ licensed journeyworker pipefitters to install or fabricate the high pressure piping.

Those who are not licensed as a master pipefitter or journeyworker pipefitter may assist in the installation of high pressure piping systems under the direct supervision of a licensed pipefitter, if they are registered in an approved pipefitter apprenticeship program, or registered with us as an unlicensed high pressure piping pipefitter.

Licensed master or journeyworker pipefitters may directly supervise no more than two unlicensed persons.

What are the requirements to become a licensed master pipefitter?

An individual must have five years of experience in the practical installation or fabrication of high pressure piping systems, apply for and be approved to take the master pipefitter exam, and receive a minimum score of 70 on the exam.

What are the requirements to become a licensed journeyworker pipefitter?

An individual must have four years of experience in the practical installation or fabrication of high pressure piping systems, apply for and be approved to take the journeyworker pipefitter exam, and receive a minimum score of 70 on the exam.

What is included in the master/journeyworker pipefitter exams?

Both examinations are drawn from the Minnesota's high pressure piping and code for power piping systems:  Minnesota Statutes Chapter 326B - sections 326B.90 to 326B.925 and Minnesota Rules Chapter 5230

Are study guides available for these exams?

 Yes. Download the high-pressure-piping license examination guide.

Other available study guides:

  • ANSI/IIAR 2-2014

  • ASME B31.5-2016

  • ASME BPE-2016

  • ASME B31.1-2016

  • ASME IX-2017

Where can I find exam forms?

The application and affidavit forms are available for download .

What are the differences among standard, time and material, and blanket permits?

  • A standard permit applies for any time a contractor has a set bid and knows the costs of labor and material for a project.

  • A time and material permit applies for any time a contractor has a project that doesn't have a set bid price.

  • A blanket permit applies for when a contractor is to receive multiple projects over the course of a calendar year at one location, such as a paper mill, power plant, sugar-beet plant, processing plant, etc.

What costs are to be included in the inspection fee formula on permits?

All costs of labor and material for the installation/fabrication of the high pressure piping project are to be included. This includes the cost of material supplied by the owner of the facility of the project. There is a worksheet with the permit application form to assist you in the calculation of these fees.