A boiler is defined as “a closed vessel in which water or other liquid is heated, steam or vapor is generated, steam is superheated, or any combination thereof, under pressure or vacuum, for use external to itself, by the direct or indirect application of heat.” Also included are fired units for heating or vaporizing liquids other than water where these units are complete within themselves. This definition includes water heaters that exceed 200,000 Btu/hr heat input or 120 gallons nominal water containing capacity.
A pressure vessel is defined as “a vessel in which the pressure is obtained from an indirect source or by the application of heat from an indirect source or a direct source, other than those included within the term ‘boiler’.” Pressure vessels include but are not
limited to compressed gas storage tanks (i.e., air, oxygen, nitrogen tanks, etc.), anhydrous ammonia tanks, hydro pneumatic tanks, autoclaves, hot water storage tanks, chemical reactors and refrigerant vessels, operating at a pressure greater than 15 psi.
North Carolina Boiler and Pressure Vessel Law
The N.C. General Assembly first enacted a law instituting regulation of high-pressure boilers in 1935. Since then, coverage has expanded to include low-pressure boilers and pressure vessels. In 1975, the General Assembly enacted the Uniform Boiler and Pressure Vessel Act, codified as Chapter 95, Article 7A, of the General Statutes. The rules are contained within the N.C. Administrative Code, Chapter 13.
Boilers installed after 1935 must be constructed in accordance with the American Society of Mechanical Engineers (ASME) Boiler and Pressure Vessel Code. Hot water storage tanks installed after 1951 and all other pressure vessels installed after 1975 must be constructed to the applicable ASME Codes.
- Hydro pneumatic (water) tank: external inspections every four years.
- All other pressure vessels: external inspections every two years.
- High Pressure Boilers:
Internal inspection annually.
External inspection annually.
- Miniature High Pressure and Hot Oil Boilers: External inspections every year.
- Heating Boilers/Hot Water Supply Boilers/ Water Heaters: External inspection every two years.
N.C. Gen. Stat. § 95-69.11 allows for inspectors “To have free access, without notice, to any location in this state, during reasonable hours, where a boiler or pressure vessel is being built, installed, or operated for the purpose of ascertaining whether
such boiler or pressure vessel is built, installed, or operated in accordance with the provisions of this article.”
North Carolina law allows for three types of pressure vessel inspectors:
- Boiler and Pressure Vessel Inspector: an employee of the NCDOL, Boiler Safety Bureau authorized to inspect any boiler or pressure vessel subject to the UniformBoiler and Pressure Vessel Act.
- Special Inspector: an employee of an insurance company authorized to insure in this state. Special inspectors may only inspect objects their company insures.
- Owner-User Inspector: a qualified individual employed on a full-time basis by a company operating pressure vessels for its own use and not for resale, and maintains an established inspection program for periodic inspection of pressure vessels owned or used by that company and where such inspection program is under the supervision of one or more engineers having qualifications satisfactory to the commissioner.
Boilers, storage tanks and other pressure retaining items are potentially dangerous. While operating, they contain large amounts of energy, which can fail instantaneously, usually with devastating results. When water changes from liquid to steam it expands about 1,600 times its original volume. In other words, 1 cubic foot of water can instantly convert to 1,600 cubic feet of steam. If a small boiler, such as a 30-gallon home water heater, were to explode and flash to steam at 332 degrees Fahrenheit, it would release enough energy to lift an average car to a height of nearly 125 feet in the air. A 50-gallon air tank operating at 150 psi has as much stored energy as 50 grams of TNT, about the same amount as a military MKII hand grenade. To ensure the continued safety of pressure equipment, it is inspected by qualified commissioned inspectors on a periodic basis. The purpose of the inspection is to help prevent such accidents from happening. Since inspections are a snapshot in time and only reveal the condition of the vessel at that moment, there is an implied duty upon the owner or operator to keep he equipment in safe and proper working order.
The inspection certificate is documented evidence that the boiler or pressure vessel has been inspected and is safe to operate under the conditions noted on the certificate. North Carolina law states that no boiler or pressure vessel subject to Chapter 95, Article 7A, may be operated without a current inspection certificate.
The Boiler Safety Bureau is fully receipt-funded and does not receive any money from the legislature. Therefore, the bureau charges a fee for its services. The fee is dependent upon the type and size of the object needing inspection, and the complexity of
work and time spent inspecting. The fees cover the inspection activity, the maintenance of a data storage system and the issuance of the inspection certificate. The schedule of fees can be found in the Administrative Code, 13 NCAC 13 .0213.
Repairs and alterations to boilers and pressure vessels must conform to the requirements of the National Board Inspection Code. Welded repairs and alterations must be made only by an individual or organization in possession of a valid certificate of authorization for use of the National Board “R” symbol stamp. Repairs and alterations must be reported on National Board “R1” and “R2” reports, respectively, as required by the NBIC. These reports are available through the National Board of Boiler and Pressure Vessel Inspectors. The reports, along with supplements used, must be submitted to the chief inspector within 60 days of the completion of the work conducted. Repair and alteration reports must be annotated with the appropriate NC identification number for the pressure equipment repaired. See the Administrative Code, 13 NCAC 13.0401, for complete rules on design, construction and repair requirements.
The Administrative Code, 13 NCAC 13 .0206, states that the owner must notify the Boiler Safety Bureau within 24 hours when a device is rendered inoperative due to an over pressurization, dry firing or any related event that causes damage to the equipment, real or personal property, personal injury, or death.
The Boiler Safety Bureau is open from 8 a.m. until 5 p.m. Monday through Friday except for legal holidays. The bureau staff are eager to help you maintain compliance with the law and to be of service to you. To find your local state inspector, visit the Boiler Safety Bureau Inspector Territory Map.
Owner responsibilities include, but are not limited to:
- Obtaining periodic inspections provided by commissioned inspectors. The inspector is not responsible for scheduling inspections. It is the owner’s responsibility to ensure that a current certificate of inspection is in force.
- Paying the required fees for the certificate of inspection.
- Maintaining a copy of the valid certificate of inspection on the premises.
- Obtaining proper repairs and involving the commissioned inspector in all repairs.
- Notifying the Boiler Safety Bureau in the event of an accident.
For objects requiring State inspection, you must submit a request from the Boiler Safety Bureau through the “Boiler Forms” tab on our website. The “New” tab is for brand new objects, or objects that already have a North Carolina registration number assigned to them. The “Used” tab is for any used equipment not having been inspected before by the Bureau. Local or County permits may be required, and you should always check with the local and/or county government where the object is to be installed.
The Boiler Safety Bureau does not issue contractor licenses for installation, nor are they addressed in the Administrative Rules. The North Carolina State Board of Examiners requires and issues contractor licenses, and we recommend you contact them for more information. They can be reached by phone at 919-875-3612, or their website at http://www.nclicensing.org/
*Please note- Some activities involving the installation of power boilers may require a Certificate of Authorization from the American Society of Mechanical Engineers.