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Boilers & Unfired Pressure Vessels: 
Installation and Other Requirements

A. Scope of Pennsylvania’s Boiler and Unfired Pressure Vessel Law

B. Requirements for Boiler Installation (if not made of cast iron)

C. Requirements for Boiler Installation (if made of cast iron)

D. Requirements for Unfired Pressure Vessel Installation

E. Periodic Inspections of Boilers or Pressure Vessels

F. Repair/Alterations of Existing Boilers or Pressure Vessels

G. Accident Reporting Requirements

H. Pennsylvania Boiler Inspector Commissions

I. Questions

J. Forms (All Boiler Division Forms)

K. Fee Schedule

L. Boiler Law and Regulations

A. Scope of Pennsylvania’s Boiler and Unfired Pressure Vessel Law

  • Pennsylvania’s Boiler and Unfired Pressure Vessel Law and its regulations require that the Department of Labor & Industry to:

  • Approve the installation or moving of all boilers and unfired pressure vessels.

  • Periodically inspect these units.

  • Issue credentials for all persons inspecting these units.

Enforcement is conducted by personnel in the Department’s Boiler Division (or by commissioned insurance inspectors).

THE FOLLOWING ARE EXEMPT FROM BOILER DIVISION INSPECTION:

  1. Boiler installations in a single-family residence (as long as a business is not located in the home) or in apartment buildings with four (4) or fewer dwelling units.

  2. Boiler installations in agricultural buildings used for farming operations (this does not include farm buildings where sales occur or where agricultural processing may occur).

  3. Boilers or unfired pressure vessels owned and operated by the federal government.

  4. Storage water heaters and instantaneous water heaters when none of the following limitations are exceeded:
    • A heat input of 200,000 BTU per hr.
    • A water temperature of 210° F.
    • A nominal water-containing capacity of 120 gallons.


  5. Unfired pressure vessels used for the transportation of compressed gases, if constructed and operated in compliance with the specifications and regulations of the U.S. Department of Transportation.

  6. Air tanks located on vehicles operating under other Commonwealth agencies’ rules and regulations, and used for carrying passengers or freight.

  7. Air tanks installed on the right-of-way of railroads and used directly in the operation of switches and signals under federal or Commonwealth jurisdiction.

  8. Unfired pressure vessels having an internal or external operating pressure not exceeding 15 psi, with no limitation on size, if equipped with approved safety devices.

  9. Unfired pressure vessels that do not exceed the following volume and pressure limits ( this does not apply to liquefied petroleum gas containers):
    • 5 cubic feet in volume and 250 psi design pressure.
    • 3 cubic feet in volume and 350 psi design pressure
    • 1 to 1 1/2 cubic feet in volume and 600 psi design pressure.


  10. Unfired pressure vessels having an inside diameter not exceeding 6”, with no limitation on length or pressure of vessel.

  11. Unfired pressure vessels with a nominal water-containing capacity of up to 120 gallons, containing water under pressure, including those containing air that is trapped in the system, the compression of which serves only as a cushion.

  12. Filters and softeners with a nominal water-containing capacity of 120 gallons or less and pressures not exceeding 100 psi at ambient temperature.

  13. Air conditioner heat exchangers (chillers) with a design pressure not exceeding 300 psi and a water temperature not exceeding 210° F.

Note: Work exempted from the Pennsylvania boiler law may be subject to the requirements of the Uniform Construction Code (UCC) --- check with the building code official having jurisdiction.

B. Requirements for Boiler Installations (if not made of cast iron)

  1. Potable water heaters which exceed 120 gallons capacity, or 200,000 btu heat input require inspection but do not require the application forms or fees mentioned below. If the potable water heater is constructed to ASME code and will satisfy the code clearance requirements (minimum of 18” in front, at rear and on both sides, and 30” in front of manhole cover if applicable, the unit may be installed without receiving permission from the Boiler Division. To notify your local inspector and arrange an inspection of your potable water heater email the boiler division at wross@pa.gov or call the Boiler Division (717-214-4319).

  2. If the boiler will satisfy the code clearance requirements (minimum of 30” in front, at rear and on both sides, and 72” overhead), do the following:
    • Submit a fully completed copy of the INTENT TO INSTALL BOILER (LIBI-302) form for each unit to be installed.

      Be sure to note the following:

      If the unit is a boiler that will be moved, you must also submit a copy of the PERMIT TO MOVE BOILER OR UNFIRED PRESSURE VESSEL (LIBI-301) form with the intent to install form.
      If the unit is new and was manufactured to the ASME code, you must include a copy of the Manufacturer’s Data Report with your submission.
    • Submit payment via check or money order made payable to Commonwealth of Pennsylvania. Click here for fee schedule.

      Note: If sending in intent forms for two boilers, the total payment fee is double the fee listed in the fee schedule. If seeking approval of three boilers in the same boiler room, the total payment will be triple the fee listed in the schedule.

    • Mail these items to:

      PA Department of Labor & Industry
      Boiler Division
      651 Boas Street, Room 1606
      Harrisburg, PA 17121

      When approved, the Boiler Division will send the applicant a copy of the INTENT TO INSTALL BOILER form with permission to install the unit noted on the copy. The form will also indicate the state inspector name and phone number to call for the final inspection. (A commissioned insurance inspector may also perform the required inspection.)

      Once the installation has been inspected and approved, the boiler may be placed in operation. The Boiler Division will issue a Certificate of Operation, upon receipt of the inspector’s inspection report and after mailing an invoice for payment of the annual certificate fee and the inspection fee. A copy of this certificate must be placed in a visible location within the boiler room.

  3. If the boiler will not satisfy the code clearance requirements (minimum of 30” in front, at rear and on both sides, and 72” overhead), do the following:

    • Submit three sets of plans for the installation drawn on paper that is not less than 18” x 24” in size and to a scale of not less than ¼ “ = 1’. These should show the floor plan with all objects in the boiler room. An elevated view showing the breaching and smoke pipe is also required, whenever the minimum overhead clearance (72”) cannot be satisfied.

    • Submit payment via check or money order made payable to Commonwealth of Pennsylvania, for each boiler. Click here for fee schedule.

      Note: If sending in intent forms for two boilers, the total payment fee is double the fee listed in the fee schedule. If seeking approval of three (3) or more boilers in the same boiler room, the total payment will be triple the fee listed in the fee schedule.

    • Submit one copy of the BOILER VARIANCE REQUEST - INDUSTRIAL BOARD PETITION (LIBI-303). Note that a separate request must be submitted for each boiler that requires a variance.

    • Submit payment via a separate check or money order made payable to Commonwealth of Pennsylvania for this Industrial Board request.

    • Mail these items to:

      PA Department of Labor & Industry
      Industrial Board
      651 Boas Street, Room 1622
      Harrisburg, PA 17121

If the Industrial Board grants the requested variance, the Boiler Division will issue a “plan letter” approving the installation, along with a copy of the Industrial Board Variance approval and two sets of plans. The plan approval letter will contain the name and phone number of the Boiler Division inspector who should be called to inspect the boiler installation. (A commissioned insurance inspector may also perform the required inspection.)

The plan letter, Industrial Board variance and one set of plans must be kept permanently in an accessible location within the boiler room.

Once the installation has been inspected and approved, the boiler may be placed in operation. The Boiler Division will issue a Certificate of Operation, upon receipt of our inspector’s inspection report and after mailing an invoice for payment of the annual certificate fee and the inspection fee. A copy of this certificate must be placed in a visible location within the boiler room.

C. Requirements for Boiler Installations (if made of cast iron)

  1. If the cast iron boiler will satisfy the code clearance requirements (minimum of 30” in front, at rear and on both sides, and 72” overhead), do the following:
    • Submit a fully completed copy of theINTENT TO INSTALL BOILER (LIBI-302) form for each unit to be installed.

      Be sure to note the following:

      If the unit is a boiler that will be moved, you must also submit a copy of the PERMIT TO MOVE BOILER OR UNFIRED PRESSURE VESSEL (LIBI-301) form with the intent to install form.
    • Submit payment via check or money order made payable to Commonwealth of Pennsylvania. Click here for fee schedule.

      Note: If sending in intent forms for two boilers, the total payment fee is double the fee listed in the fee schedule. If seeking approval of three boilers in the same boiler room, the total payment will be triple the fee listed in the fee schedule.

    • Mail these items to:

      PA Department of Labor & Industry
      Boiler Division
      651 Boas Street, Room 1606
      Harrisburg, PA 17121

When approved, the Boiler Division will send a copy of the INTENT TO INSTALL BOILER form with permission to install the unit noted on the copy. The form will also indicate the inspector name and phone number to call for the hydrostatic test. (A commissioned insurance inspector may also perform the required inspection.)

At the time that the required hydrostatic test occurs, you must submit a fully completed copy of the CAST IRON BOILER INSTALLATION REPORT (LIBI-236) for each unit to be installed. The hydrostatic test will be conducted at 1½ times the Maximum Allowable Working Pressure for hot water boilers and 45 psi for steam boilers.

Once the installation has been inspected and approved, the boiler may be placed in operation. The Boiler Division will issue a Certificate of Operation, upon receipt of the inspector’s inspection report and after mailing an invoice for payment of the annual certificate fee and the inspection fee. A copy of this certificate must be placed in a visible location within the boiler room.

  1. If the cast iron boiler will not satisfy the code clearance requirements (minimum of 30” in front, at rear and on both sides, and 72” overhead), do the following:
    • Submit three sets of plans for the installation drawn on paper that is not less than 18” x 24” in size and to a scale of not less than ¼ “ = 1’. These should show the floor plan with all objects in the boiler room. An elevated view showing the breaching and smoke pipe is also required, whenever the minimum overhead clearance (72”) cannot be satisfied.

    • Submit payment via check or money order made payable to Commonwealth of Pennsylvania, for each boiler. Click here for fee schedule.

      Note: If sending in intent forms for two boilers, the total payment fee is double the fee listed in the fee schedule. If seeking approval of three (3) or more boilers in the same boiler room, the total payment will be triple the fee listed in the fee schedule.

    • Submit one copy of the BOILER VARIANCE REQUEST - INDUSTRIAL BOARD PETITION (LIIB-303). Note that a separate request must be submitted for each boiler that requires a variance.

    • Submit payment via a separate check or money order made payable to Commonwealth of Pennsylvania for this Industrial Board request.

    • Mail these items to:

      PA Department of Labor & Industry
      Industrial Board
      651 Boas Street, Room 1622
      Harrisburg, PA 17121

If the Industrial Board grants the needed variance, the Boiler Division will issue a “plan letter” approving the installation, along with a copy of the Industrial Board Variance approval and two sets of plans. The plan approval letter will contain the name and phone number of the Boiler Division inspector who should be called to inspect the boiler installation. (A commissioned insurance inspector may also perform the required inspection.)

At the time that the required hydrostatic test occurs, you must submit a fully completed copy of the CAST IRON BOILER INSTALLATION REPORT (LIBI-236) for each unit to be installed. The hydrostatic test will be conducted at 1½ times the Minimum Allowable Working Pressure for hot water boilers and 45 psi for steam boilers.

Once the installation has been inspected and approved, the boiler may be placed in operation. The Boiler Division will issue a Certificate of Operation, upon receipt of our inspector’s inspection report and after mailing an invoice for payment of the annual certificate fee and the inspection fee. A copy of this certificate must be placed in a visible location within the boiler room.

D. Requirements for Unfired Pressure Vessel Installation

  1. If the unfired pressure vessel ASME code constructed and will satisfy the code clearance requirements (minimum of 18” in front, at rear and on both sides, and 30” in front of manhole cover, the unit may be installed without receiving permission from the Boiler Division.

    After the unfired pressure vessel has been installed and before placing it in use, the unit must be inspected and approved.

    If your insurance carrier has a commissioned inspector, call the company and arrange for the inspection.

    If your insurance carrier does not have a commissioned inspector, you must email the boiler division at wross@pa.gov or call the Boiler Division (717-214-4319), to make arrangement for the required inspection. You may also fax this request to 717-705-7262. If you fax in the request, be sure to include a telephone number where we can reach you during normal business hours (8 AM to 5 PM).

    Once the inspection has been passed, the unfired pressure vessel may be used. The Boiler Division will issue a Certificate of Operation, upon receipt of our inspector’s inspection report and after mailing an invoice for payment of the annual certificate fee and the inspection fee. A copy of this certificate must be placed in a visible location within the boiler room.

  2. If the unfired pressure vessel will not satisfy the code clearance requirements (minimum of 18” in front, at rear and on both sides, and 30” in front of manhole cover, do the following:

    • Submit one copy of the UNFIRED PRESSURE VESSEL VARIANCE REQUEST - INDUSTRIAL BOARD PETITION (LIIB-305). Note that a separate request must be submitted for each vessel that requires a variance.

    • Submit payment of via check or money order made payable to Commonwealth of Pennsylvania, for this Industrial Board request.

    • Mail these items to:

      PA Department of Labor & Industry
      Industrial Board
      651 Boas Street, Room 1622
      Harrisburg, PA 17121

    If the Industrial Board grants the needed variance, the Boiler Division will mail a copy of the Industrial Board order to the owner.

    Once the installation has been inspected and approved, the vessel may be placed in operation. The Boiler Division will issue a Certificate of Operation, upon receipt of our inspector’s inspection report and after mailing an invoice for payment of the annual certificate fee and the inspection fee. This certificate should be placed in a visible location within the room where the unfired pressure vessel is located.

E. Periodic Inspections of Boilers or Pressure Vessels

All boilers and pressure vessels that must comply with Pennsylvania’s Boiler and Unfired Pressure Vessel Law and its regulations are subject to periodic inspections.

These periodic inspections must be conducted by an individual holding a current Pennsylvania boiler inspector commission. If your insurance carrier has a commissioned inspector, call the company and arrange for the inspection.

If your insurance carrier does not have a commissioned inspector, you must call the Boiler Division (717-214-4319), to make arrangement for the required inspection. You may also fax this request to 717-705-7262. If you fax in the request, be sure to include a telephone number where we can reach you during normal business hours (8 AM to 5 PM).

Field inspections shall be conducted in accordance with the following:

  • Power boilers and process boilers will be inspected internally and externally while not under pressure every 12 months. However, the Department may extend power boiler internal inspections to 24 months and process boiler internal inspections to 60 months, if the boiler passes an annual external inspection and the requirements found in section 3a.111(2) of the regulation.

  • Internal and external inspection of low-pressure steam vapor boilers that are not under pressure will be conducted every 24 months.

  • External inspection of hot water supply boilers will be conducted every 24 months. An inspector may require internal inspection because of a vessel's age or condition. The Department will notify the boiler owner or operator verbally or in writing of the need for an internal inspection.

  • Internal inspection of steel hot water heating boilers will be conducted every 48 months. External inspections will be conducted every 24 months.

  • Internal and external inspections of low-pressure boilers in schools will be conducted every 24 months.

  • External inspections of cast iron boilers will be conducted every 24 months and will include an internal inspection of the firebox. The unit shall be flushed until clean if the watersides appear to contain sludge.

  • Unfired pressure vessels will be inspected every 36 months. An inspector may require internal inspections because of a vessel's age or condition. The Department will notify the boiler owner or operator verbally or in writing of the need for an internal inspection.

Owners or users must prepare a boiler or unfired pressure vessel for internal inspection in accordance with the ANSI/NB23 after an inspector provides notification. Inspectors will not inspect a boiler or unfired pressure vessel that is not properly prepared for an internal inspection.

F. Repair/Alteration of Boilers or Pressure Vessels

If repairs or alteration are necessary to an approved boiler or pressure vessel, a commissioned inspector must first be called for consultation and recommendations as to the best method of making such repairs.

Repairs or alterations must comply with all applicable provisions of the National Board Inspection Code (ANSI/NB 23).

Only manufacturers or repair companies holding a National Board “R” stamp may perform welded repairs, alterations or tube replacements.

G. Accident Reporting Requirements

All accidents or explosions involving boilers or unfired pressure vessels within the scope of Pennsylvania’s Boiler and Unfired Pressure Vessel Law are subject to the following special notification requirements.

Immediately following (within 24 hours) of the incident, the owner, user or operator must notify the Department of the accident. This may be done via one of the following means:

  1. Telephone call to 717-772-2443.

  2. Faxed message to 717-705-7262

  3. E-mail to wross@pa.gov

  4. Hand carried message delivered to:

    PA Department of Labor & Industry
    Boiler Division
    651 Boas Street, Room 1606
    Harrisburg, PA 17121

Upon notice of the accident, a Department inspector will be assigned to conduct an investigation.

Until such time as a Department inspector arrives to investigate the incident, no one should remove or otherwise disturb the boiler, pressure vessel or related parts or equipment, unless absolutely necessary to prevent harm to persons or property.

Before the unit is brought back into service, it must pass inspection.

Within five (5) days of the accident, the owner, user or operator must file a fully completed copy of a BOILER OR UNFIRED PRESSURE VESSEL ACCIDENT REPORT (LIBI-306).

This should be faxed (717-705-7262) or mailed to the following address:

PA Department of Labor & Industry
Boiler Division
Room 1614, L&I Building
651 Boas Street
Harrisburg, PA 17121

H. Pennsylvania Boiler Inspector Commissions

An individual must hold a current Pennsylvania Inspector Commission to inspect boilers and unfired pressure vessels in the Commonwealth. To obtain a Pennsylvania Commission, an individual must satisfy one of the criteria listed below.

  1. Be an employee of a company that is authorized to insure boilers and unfired pressure vessels.

  2. Be an employee of a boiler or unfired pressure vessel owner that has authorized them to perform inspections on boilers or unfired pressure vessels that are involved in process operations.

  3. Be employed by the Commonwealth of Pennsylvania.

The Department of Labor and Industry offers examinations for Pennsylvania State Inspector Commissions throughout the year. Applicants must apply at least one month before they schedule to take the exam.

To apply, submit all of the following:

  • An APPLICATION FOR PENNSYLVANIA BOILER INSPECTOR COMMISSION (LIBI-304) form.

  • A copy of a valid National Board Commission Card.

  • Printed verification that the applicant’s company is authorized to write insurance in Pennsylvania to insure boilers and unfired pressure vessels or that the applicant is an employee of a boiler or unfired pressure vessel owner that has authorized them to perform inspections on boilers or unfired pressure vessels that are involved in process operations.

  • Payment in the amount of the total fee for the examination and for the credential card via check or money order made payable to Commonwealth of Pennsylvania. Click here for fee schedule.

An applicant who fails to pass the initial PA Inspector Commission examination is entitled to take the exam two additional times, if taken within a one-year period, without paying additional fees.

A PA Commission is valid for one (1) calendar year.

To renew a Pennsylvania Commission, individuals must submit the following:

  • An APPLICATION FOR PENNSYLVANIA BOILER INSPECTOR COMMISSION (LIBI-304) form.

  • A copy of their PA Commission Credential Card.

  • A copy of their valid National Board Commission Card.

  • Printed verification that the applicant’s company is authorized to write insurance in Pennsylvania to insure boilers and unfired pressure vessels or that the applicant is an employee of a boiler or unfired pressure vessel owner that has authorized them to perform inspections on boilers or unfired pressure vessels that are involved in process operations.

  • A check or money order in the amount of the fee for the new credential card.

Information pertaining to the National Board commission examination can be found at: www.nationalboard.org.

Applications and appropriate fees should be mailed to:

Department of Labor & Industry
Certifications, Accreditations & Licensing Division
651 Boas Street, Room 1606
Harrisburg, PA 17121

Contact the Certification, Accreditation and Licensing Division at 717-772-3396, if you have any questions about obtaining a PA Commission.

I. Questions

If you have questions about the Department of Labor & Industry’s boiler or unfired pressure vessel requirements that are not answered on these web pages, write, email, call or fax the Department at:

PA Department of Labor & Industry
Boiler Division
651 Boas Street, Room 1606
Harrisburg, PA 17121
 
EMAIL: boilers@pa.gov
PHONE: 717-214-4319
FAX: 717-705-7262

J. Forms (All Boiler Division Forms)

Cast Iron Boiler Installation Report (LIBI-236)

Permit to Move Boiler or Unfired Pressure Vessel (LIBI-301)

Intent to Install Boiler (LIBI-302)

Boiler Variance Request - Industrial Board Petition (LIIB-303)

Unfired Pressure Vessel Variance Request - Industrial Board Petition (LIIB-305)

Water Heater Variance Request – Industrial Board Petition (LIIB-304)

Application to Take PA Boiler Inspector Commission Exam or Renew Commission (LIBI-304)

Boiler or Unfired Pressure Vessel Accident Report (LIBI-306)

Request for PA Special Number (LIBI-805)

K. Fee Schedule

L. Boiler Law and Regulations

Click on one of the links below to access a copy of the Boiler Law and the regulations implementing this law.

Boiler and Unfired Pressure Vessel Law (Act 104 of 2013)

Boiler and Unfired Pressure Vessel Regulations