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COMMONWEALTH OF PENNSYLVANIA

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PA Bulletin, Doc. No. 04-1996b

[34 Pa.B. 6033]

[Continued from previous Web Page]

§  3a.29. Discharge outlets.

   Discharge of safety valves of a boiler generating in excess of 500 pounds of steam per hour must be piped to the outside atmosphere and to a safe point of discharge. Blowoff pipes and other outlets must be located to prevent injury to personnel.

§ 3a.30. Electric boilers.

   Appliances required for electric boilers must be attached to the boilers in accordance with the following requirements:

   (1)  A cable must be provided for grounding the boiler shell and shall be the same gauge as the incoming power line to the boiler. The cable must be permanently connected and grounded.

   (2)  A suitable screen or guard must be placed around high-tension bushings with a sign containing a high voltage warning. The screen or guard must be located to prevent a person from accidentally coming in contact with the high-tension circuit.

   (3)  The power circuit to the boiler must be open when safety valves are adjusted.

   (4)  The power line must be open when the boiler is under steam pressure and the operator is making a necessary adjustment.

   (5)  Safety or relief valves must have a relieving capacity of 3 1/2 pounds per hour for each kilowatt rating.

   (6)  Boiler shell grounding connectors must be installed in accordance with all of the following:

   (i)  The NEC, Chapter 4, except that the cable gauge size must comply with paragraph (1).

   (ii)  A conductor will be permanently attached to the boiler shell by suitable lugs, pressure connectors, clamps, or other Department-approved means. Connectors that depend on solder to maintain connection may not be used.

§ 3a.31. Forced circulation boilers.

   Forced circulation boilers and boilers with no fixed steam or waterline must conform to the ASME Code, section 1.

§ 3a.32. Supports.

   (a)  A boiler or unfired pressure vessel must be supported by masonry or structural supports sufficient to safely support the boiler or vessel and its contents.

   (b)  An air compressor vessel must be shock mounted.

§ 3a.33. Explosion doors.

   Stoker coal fired boilers under positive pressure must be equipped with explosion doors to relieve furnace pressure. The explosion doors will be located in the setting wall within 7 feet of the firing floor or any platform, and provided with substantial deflectors to divert the blast away from personnel.

§ 3a.34. Ventilation for combustion equipment.

   Adequate air to support combustion must be provided. The recommendations of the manufacturer of the equipment must be utilized.

§ 3a.35. Ladders and runways.

   (a)  Walkways, runways and platforms are required between and on top of boilers, which are more than 8-feet high from the operating floor to afford accessibility for the operation and servicing.

   (b)  Walkways, runways and platforms must meet the following requirements:

   (1)  Constructed of metal.

   (2)  Constructed of safety treads, standard grating, or similar material with a minimum clear width of 30 inches.

   (3)  Constructed by bolts, welds or rivets.

   (4)  Equipped with handrails that are 42-inches high with an intermediate rail and 6-inch toeboard.

   (c)  A stairway that is a means of access to the walkways, runways or platforms must not exceed an angle of 45°.

   (d)  A ladder that serves as a means of access to walkways, runways or platforms must be constructed:

   (1)  Of metal.

   (2)  So the rungs extend through the side members and are permanently secured to the side rails.

   (3)  So the front of the rungs have a distance of at least 30 inches from the nearest permanent object on the climbing side of the ladder.

   (4)  So the back of the rungs have a distance of at least 6 1/2 inches from the nearest permanent object.

   (5)  So there is a clear width of at least 15 inches from the centerline of the ladder on either side across the front of the ladder.

   (e)  A welder qualified under Standard Qualification Procedures of the American Welding Society is required for welding a walkway, runway, platform or ladder.

   (f)  A walkway, runway or platform exceeding 6 feet in length must have at least two means of exit access.

§ 3a.36. Clearances.

   (a)  The following clearances apply for boilers installed after January 1, 1960:

   (1)  The minimum clearance around each boiler must be 30 inches with at least 6 feet clearance from the floor to overhead obstructions.

   (2)  The minimum clearance around each unfired pressure vessel must be 18 inches. The minimum clearance in front of a manhole cover shall be 30 inches.

   (3)  A clearance of at least 12 inches must be provided between the floor and lower head or the underside of the shell of an unfired pressure vessel. The clearance distance must be the measurement from a vessel appendage to the next object.

   (b)  The following requirements apply to a single installation or assembly of storage water heaters or instantaneous water heaters, which operate as a unit:

   (1)  The unit may be arranged with a minimum clearance of 6 inches between components if an 18-inch clearance shall be maintained around the assembly. The clearance in front of a manhole opening is a minimum of 30 inches.

   (2)  An assembly may not exceed 9 million BTU input.

   (3)  Casings must be readily removable for inspection purposes, if casings are provided.

   (c)  A new building containing multiple boiler installations must meet the following minimum overhead clearance requirements:

   (1)  Between the boiler platform and the ceiling: 7 feet.

   (2)  Between the top of the boiler proper and the ceiling for all installations: 3 1/2 feet.

   (3)  Between the highest point of any valve or fitting and the ceiling: 6 inches.

   (d)  Subsections (a) and (b) do not apply to pressure vessels of factory assembled package units that are governed by § 3a.111 (relating to field inspections) if there is adequate clearance for operation and inspection. Subsection (a) applies to the entire factory assembled unit.

   (e)  The minimum clearance around a wall-hung boiler must be 30 inches except for the wall mount side.

   (f)  The clearance between modules in a modular system may be reduced to the manufacturer's recommendations if the entire modular boiler system meets the 30-inch clearance requirement of subsection (a)(1).

   (g)  This section does not apply to a miniature boiler if the boiler can be safely inspected as installed.

   (h)  Tripping hazards are not permitted.

§ 3a.37. Special design.

   (a)  The owner or user of a new boiler or unfired pressure vessel having unusual features of special design intended for installation and operation in this Commonwealth may submit all of the following to the Department for approval:

   (1)  Duplicate complete specifications.

   (2)  Drawings that show all details of the proposed construction and the method of computation used in determining the safe working pressure for each new boiler and unfired pressure vessel.

   (b)  A specially designed boiler or unfired pressure vessel may not be operated until the Department approves its design.

§ 3a.38. Commercial beverage dispensing systems.

   (a)  An unfired pressure vessel used in a commercial beverage dispensing system must have clearance of 18 inches for at least 50% of the vessel surface. The remaining vessel surface may have its clearance reduced to 1 inch.

   (b)  The Department will issue one certificate of operation and charge one fee under § 3a.2 (relating to fees) for all vessels used in a commercial dispensing system at a single business location at the same design maximum working pressure.

§ 3a.39. Manufactured parts.

   Parts manufactured for boilers or unfired pressure vessels constructed to the ASME Code must be manufactured and stamped in accordance with the applicable section of the ASME Code. Data reports must be furnished in accordance with the applicable section of the ASME Code.

INSTALLATIONS OF POWER BOILERS

§ 3a.51. Compliance with the ASME Code for power boilers.

   Installations of power boilers must comply with the provisions of Section 1 of the ASME Code, ASME/CSD1 and NFPA 85.

INSTALLATIONS OF LOW-PRESSURE HEATING BOILERS

§ 3a.61. Compliance with the ASME Code for low-pressure boilers.

   Installations of low-pressure heating boilers must comply with section IV of the ASME Code and ASME/CSD 1.

§ 3a.62. Registration and installation.

   (a)  An installer of low-pressure steel heating boilers shall provide a copy of the manufacturer's data report to the inspector when the boiler is installed.

   (b)  A cast iron boiler must be hydrostatically tested when it is installed. The inspector may accept the factory hydrostatic test.

   (c)  An installer of low-pressure cast iron boilers shall submit a ''Cast Iron Installation Report'' to the Department on a Department-provided form. The Cast Iron Installation Report contains manufacturer, testing and installation information.

INSTALLATIONS OF UNFIRED PRESSURE VESSELS

§ 3a.71. Compliance with the ASME Code for installations of unfired pressure vessels.

   Installations of unfired pressure vessels must comply with sections VIII or X of the ASME Code.

REPAIRS AND ALTERATIONS

§ 3a.81. Major repairs and alterations.

   (a)  An owner or user of a boiler or unfired pressure vessel shall consult with an inspector on a repair that affects the working pressure or safety of a boiler or unfired pressure vessel.

   (b)  A repair to a boiler or unfired pressure vessel must comply with the applicable provisions of the ASME Code or ASNI/NB 23. A manufacturer or repair company may not perform welded repairs and tube replacements without holding an ''R'' Stamp.

   (c)  An owner or user of a boiler or unfired pressure vessel shall consult with the inspector responsible for completing the report of welded repair before commencement of work or repairs that alter the original design of a boiler or unfired pressure vessel. A manufacturer holding the appropriate ASME Code stamp may alter a boiler or vessel. A manufacturer holding an ASNI/NB 23 ''R'' stamp may perform alterations to other vessels.

   (d)  All welds shall be documented on a Department-issued ''Record of Welded Repair Form'' or a R-1 form. Hydrostatic testing of welded repairs may be conducted at the inspector's discretion in accordance with ANSI/NB23.

   (e)  An owner or user of a boiler or unfired pressure vessel that requires an inspection under this chapter shall immediately notify the Department when a defect affecting the safety of the boiler or unfired pressure vessel is discovered.

§ 3a.82. Reconstruction and repair.

   Workmanship, materials, fittings and attachments used in the reconstruction or repair of a boiler or unfired pressure vessel must meet ANSI/NB 23. The boiler or unfired pressure vessel may not become operational until an inspector approves all repairs.

§ 3a.83. Repairs by welding.

   (a)  Welding repairs must comply with section IX of the ASME Code.

   (b)  A repair to a boiler or unfired pressure vessel that involves welding may be made if an inspector approves the repair and signs a record of welded repairs.

   (c)  Repairs by fusion welding must comply with ANSI/NB 23.

   (d)  Repairs listed as routine in ANSI/NB 23 may be preapproved by an inspector.

Subchapter C. ADMINISTRATION

§ 3a.91. Certificates of operation.

   (a)  The Department will issue a certificate of operation for a boiler or unfired pressure vessel upon receipt of an inspection report indicating that the boiler or unfired pressure vessel is safe to operate at the pressure limit listed in the inspection report.

   (b)  The owner or user shall post the certificate in a visible location that is as close as possible to the boiler or unfired pressure vessel.

§ 3a.92. Unsafe operation.

   The Department will suspend the certificate of operation and seal a boiler or unfired pressure vessel that is unsafe. A person, firm, partnership or corporation operating a boiler or unfired pressure vessel with a suspended certificate of operation is subject to the penalties of section 19 of the act. (35 P. S. § 1331.19)

§ 3a.93. Insurance notification.

   An owner or user shall notify the Department within 30 days when insurance is written, cancelled, not renewed, or suspended on a boiler or unfired pressure vessel. The owner or user shall notify the Department within 30 days of the cause of any suspension or refusal to renew insurance on a boiler or unfired pressured vessel.

§ 3a.94. Accident notification.

   (a)  Under section 16 of the act (35 P. S. § 1331.16), the owner or user shall immediately notify the Department by telephone, facsimile transmission, electronic mail or messenger of an accident or explosion. The owner or user shall file a written report with the Department on a Department-prescribed form within 5 days of the accident.

   (b)  The boiler or unfired pressure vessel, its parts or equipment involved in the accident or explosion may not be removed or disturbed before a Department inspection is made except to prevent harm to persons or property.

§ 3a.95. Restamping.

   (a)  An inspector will instruct the owner or user to restamp a boiler or unfired pressure vessel when the stamping becomes indistinct or detached. The owner or user shall submit a request for restamping the boiler or unfired pressure vessel to the Department. The request must be accompanied with proof of the original stamping consisting of a rubbing of the original stamping or a copy of the manufacturer's data sheet.

   (b)  A Department inspector has sole authorization to perform the Department restamping. The restamping will contain the same information, as the original stamping The Department will not restamp the ASME symbol.

§ 3a.96. Condemnation.

   (a)  A Department inspector will stamp an unsafe boiler or unfired pressure vessel with the following designation:

   Pa < XX >

   (b)  A Department inspector will place the stamping above the Commonwealth or National Board stamping. The stamping will at least 5/16 inch in height.

   (c)  A Department inspector will remove the stamping of subsection (b) when a boiler or unfired pressure vessel has been restored or repaired to comply with this chapter. No other person may remove the stamping.

§ 3a.97. Removal from service.

   An owner or user shall notify the Department when a boiler or unfired pressure vessel is removed from service for a repair or alteration within 10 days.

§ 3a.98. Reinstallation.

   (a)  Fittings and appliances used for the reinstallation of a boiler and pressure vessel must comply with this chapter.

   (b)  The owner or user of a boiler or unfired pressure vessel shall notify the Department within 10 days of the new location of a boiler or unfired pressure vessel that is moved.

   (c)  The owner or user may not place a reinstalled boiler or unfired pressure vessel into service until it passes a Department inspection.

§ 3a.99. Plan approval.

   (a)  Installation of a boiler must comply with all of the requirements of this section.

   (b)  A boiler owner shall submit an intent to install form or other data showing compliance with the provisions of the act and this chapter to the Department before a boiler is installed.

   (c)  A boiler owner shall submit drawings and a request for a variance to the Industrial Board if the installation clearances do not meet the requirements of § 3a.36 (relating to clearances). Drawings must be at least 18 inches by 24 inches in size drawn to scale of not less than 1/4 inch equals one foot. Drawings for boiler installations must include the following:

   (1)  A floor plan and section of the boiler room.

   (2)  The proposed location of all boilers, drums, headers, doors, steam, air and water gages, safety devices, blowoffs, all necessary piping, and all other parts and equipment.

   (3)  The exit ways from all of the following:

   (i)  Boiler rooms.

   (ii)  Blowoff pits and ashpits or alleys.

   (iii)  High pressure steam line tunnels.

   (iv)  Other places where there is danger to persons in confined space in case of explosion.

   (v)  Platforms.

   (4)  Walkways located over boilers.

   (5)  Clearance dimensions above, around and between boilers, equipment and other construction.

§ 3a.100. Notice of deficiency.

   (a)  The Department will use the following procedures if an inspection reveals any violation of the act or this chapter:

   (1)  The Department will issue a written notice of deficiency to the boiler or unfired pressure vessel owner or user. The notice will contain a description of the violations and an order requiring correction of the violations and repairs within 30 days of the date of issuance. When a violation relates to the unsafe operation of a boiler, the Department will act under § 3a.92 (relating to unsafe operation).

   (2)  The written notice of deficiency will include a certification requiring the boiler or unfired pressure vessel owner or user to sign, date and return the certification when the corrective action or repair has occurred. The Department may inspect the boiler or unfired pressure vessel to verify the corrective action or repair.

   (3)  If the unfired pressure vessel owner or user does not correct the deficiency within the period of time allowed in the notice of deficiency, the Department may initiate action to seal the boiler or unfired pressure vessel by issuing an order to show cause to the boiler or unfired pressure vessel owner or user.

   (4)  The order to show cause must contain a statement of the grounds for the action, the alleged violations of the act and this chapter and notification that the boiler or unfired pressure vessel may be sealed. The order to show cause must contain notification that the owner or user shall submit a written answer within 30 days. The Department will serve the order to show cause upon the owner or user by certified mail or personal service.

   (5)  The owner or user may file a written answer to the order to show cause with the Department within 30 days following service of the order to show cause. The answer must contain specific admissions or denials of the allegations contained in the order to show cause and set forth the specific facts, matters of law or regulation interpretation relied upon by the owner or user. The answer may contain a request for a variance or an extension of time for compliance.

   (b)  The Department will consider a timely-filed request for variance or extension of time, or a timely-filed appeal as a stay to an enforcement action unless the Department acts under § 3a.92 (relating to unsafe operation) or the boiler constitutes a danger to life or property under section 11(e) of the act (35 P. S. § 1331.11(e)).

   (c)  The Department will inspect the boiler or unfired pressure vessel at the expiration of an extension of time or other time period granted for compliance under this section. If the boiler or unfired pressure vessel violates the act or this chapter following inspection, the Department may seal or condemn the boiler or unfired pressure vessel under section 13 of the act (35 P. S. § 1331.13). The Department will serve the seal order upon the owner or user by certified mail or personal service.

   (d)  Under section 13 of the act, the Department will issue a notice to discontinue operation to the boiler or unfired pressure vessel owner or user for a violation that was not corrected. The notice to discontinue operation will require the owner or user to discontinue the use of the boiler or unfired pressure vessel within 24 hours. The boiler or unfired pressure vessel may not be returned to service until the violations have been corrected, the repairs have been made and the Department notifies the owner or user that the boiler or unfired pressure vessel may be returned to service.

   (e)  Subsection (a) supplements 1 Pa. Code §§ 35.14 and 35.37 (relating to orders to show cause; and answers to orders to show cause).

§ 3a.101. Appeals.

   (a)  A person aggrieved by a notice of deficiency or a notice to discontinue operation may appeal the order to the Industrial Board within 30 days of the issuance of the order.

   (b)  The Industrial Board will decide petitions for variances and extensions of time, and appeals of Department decisions.

   (c)  The Board may consider the following factors, among others, when reviewing and ruling upon a request for an extension of time or a variance or other appropriate relief:

   (1)  The reasonableness of the Department's rule and regulations as applied in the specific case.

   (2)  The extent to which an extension of time or a variance will subject occupants to unsafe conditions.

   (3)  The availability of professional or technical personnel needed to come into compliance.

   (4)  The availability of materials and equipment needed to come into compliance.

   (5)  The efforts being made to safeguard occupants against boiler and unfired pressure vessel hazards.

   (6)  The efforts being made to come into compliance as quickly as possible.

   (7)  Compensatory safety features which will provide an equivalent degree of protection for the occupants.

Subchapter D. INSPECTIONS

§ 3a.111. Field inspections.

   The Department will conduct field inspections according to the following timetable:

   (a)  Power boilers and process boilers will be inspected internally and externally while not under pressure every 12 months except as provided under section 9(e) and (f) of the act (35 P. S. § 1331.9(e) and (f)).

   (b)  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 all of the following requirements are met:

   (1)  There is continuous boiler water treatment under the direct supervision of a person trained and experienced in water treatment for controlling and limiting corrosion and deposits.

   (2)  The records are available for review and contain all of the following:

   (i)  The date and time the boiler was out of service and the reason for being taken out of service.

   (ii)  Daily analysis of water samples showing water conditions and elements or characteristics that produce corrosion or other deterioration to the boiler or its parts.

   (3)  An inspector performed annual inspections of the boiler, which included inspection of the items contained in paragraphs (1) and (2).

   (4)  The boiler is operated under direct supervision of a trained operator.

   (5)  Inspection records demonstrate no significant scaling, corrosion, erosion or overheating.

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

   (d)  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.

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

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

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

   (h)  Unfired pressure vessels will be inspected every 36 months. An inspector may require internal inspections because of a vessel's age or condition.

§ 3a.112. Inspection preparation.

   (a)  An owner or user shall prepare a boiler or unfired pressure vessel for internal inspection in accordance with the ANSI/NB23 after a inspector provides notification.

   (b)  The inspector will not inspect a boiler or unfired pressure vessel that is not properly prepared for an internal inspection.

§ 3a.113. Inspection accessibility.

   Underground-unfired pressure vessels must be installed or reinstalled in a manner that allows for external inspection of the vessel after _____ (Editor's Note: The blank refers to the effective date of adoption of this proposed rulemaking.).

§ 3a.114. Removal of covering for inspection.

   An owner or user shall remove a portion of the jacketing, setting wall or other form of casing or housing so an inspector may view rivet size and pitch, and other data necessary to determine the safety of a boiler or unfired pressure vessel when a portion of the jacketing, setting wall or other form of casing or housing is not visible and there is no other means to obtain this information.

§ 3a.115. Hydrostatic pressure test.

   (a)  A hydrostatic pressure test must comply with the following requirements:

   (1)  A hydrostatic pressure test may not exceed the following pressures:

   (i)  For boilers or unfired pressure vessels in the field, 1.5 times the maximum allowable working pressure.

   (ii)  For boilers of locomotives, 1.25 times the maximum allowable working pressure.

   (iii)  For glass-lined unfired pressure vessels, the maximum allowable working pressure.

   (iv)  For unfired pressure vessels fabricated to ASME section VIII, division 1 after January 1, 2000, 1.3 times the maximum allowable working pressure.

   (v)  For unfired pressure vessels fabricated to ASME Section VIII, Divisions 2 and 3, the pressure that was preapproved by an inspector.

   (2)  Pressure must be controlled at all times and may not be more than 106% of the test pressure allowed by the ASME Code at the time of construction.

   (3)  The temperature of the water used to apply the test must be between 70° and 120°F. If the temperature of the surrounding atmosphere is below 70°F or above 120°F, the test may not be performed.

   (4)  A safety valve must be removed or each valve shall be held to its seat by a testing clamp. Screwing down the compression screw upon the spring is prohibited. A VR stamp holder must reseal the valves.

   (5)  Pressure must be equal to or below the release pressure of the safety valve having the highest release setting when a test is applied to an existing installation to determine tightness.

   (b)  An inspector may require a hydrostatic test after the completion of a repair to insure the pressure containing boundaries hold design pressure.

§ 3a.116. Inspection during construction.

   An inspector shall comply with ASME requirements for inspections of cast iron boilers in construction.

§ 3a.117. Inspection report.

   An inspector shall submit a copy of each boiler or unfired pressure vessel inspection to the Department no more than 30 days after the inspection.

Subchapter E. BOILERS INSTALLED PRIOR TO JULY 1, 1916, AND UNFIRED PRESSURE VESSELS AND POWER BOILERS INSTALLED PRIOR TO SEPTEMBER 1, 1937

§ 3a.131. Allowable working pressure.

   The ASME Code governs calculation of allowable working pressure.

§ 3a.132. Fusible plugs.

   Fire-actuated fusible plugs may be used if the plugs conform to the requirements of Sections A19--A21, Appendix A, section I of the ASME Code. The plugs must be replaced annually.

§ 3a.133. Repair and replacement.

   Repairs or replacements to fittings or appliances must comply with the requirements for installations in the ASME Code and ASME/CSD1.

§ 3a.134. Weighted safety valves.

   Weighted safety values may not be used on boilers or unfired pressure vessels.

Subchapter F. LOW PRESSURE HEATING BOILERS INSTALLED PRIOR TO JULY 1, 1916

§ 3a.141. Riveted boilers.

   (a)  The ASME Code governs the determination of the maximum allowable working pressure on the shell of a riveted heating boiler.

   (b)  The maximum allowable working pressure of a steam heating boiler may not exceed 15 psig.

   (c)  The maximum allowable working pressure of a hot water boiler may not exceed 160 psig at a temperature not exceeding 250°F.

§ 3a.142. Welded boilers.

   The maximum allowable working pressure on the shell of a welded steel or wrought iron heating boiler may not exceed the requirements of ASME Code, section IV.

§ 3a.143. Cast iron boilers.

   (a)  The maximum allowable working pressure on the shell of a cast iron boiler may not exceed 15 psig for a steam boiler and the stamped working pressure for a hot water boiler.

   (b)  The maximum allowable working pressure for a boiler having a cast iron shell or heads, and steel or wrought iron tubes may not exceed 15 psig for a steam boiler and the stamped working pressure for a hot water boiler.

§ 3a.144. Safe pressure.

   An inspector may reduce the operating pressure of a heating boiler if the inspector determines that the boiler is unsafe for operation at the approved pressure and the boiler is not properly repaired. The inspector may reduce the operating pressure based upon the remaining thickness of the pressure boundaries and code of construction requirements.

§ 3a.145. Steam stop valves.

   (a)  A boiler equipped with a steam stop valve must contain a check valve in the condensate return line between the boiler and the system.

   (b)  A heating system equipped with a steam stop valve must have a check valve in the condensate return pipe from the part of the system equipped with the steam stop valve.

Subchapter G. UNFIRED PRESSURE VESSELS INSTALLED PRIOR TO SEPTEMBER 1, 1937

§ 3a.151. Maximum allowable working pressure.

   (a)  The maximum allowable working pressure on the shell of an unfired pressure vessel is determined by the following:

   (1)  The strength of the weakest course completed from the thickness of the plate.

   (2)  The tensile strength of the plate.

   (3)  The efficiency of the longitudinal joint.

   (4)  The inside diameter of the course.

   (5)  The safety factor allowed by the ASME Code.

   (b)  The equation for computing the maximum allowable working pressure is:

TS × T × E = Maximum allowable working pressure in     psi where:
   R × FS

   (1)  TS equals the ultimate strength of the shell plates in psi. If the tensile strength is not known, 55,000 psi must be used for temperatures not exceeding 700° F.

   (2)  T equals the maximum thickness of shell plates of weakest course in inches.

   (3)  E equals the efficiency of longitudinal joint depending upon construction.

   (i)  ANSI/NB 23, Appendix C, sections A-1 to A-9 must be used to calculate efficiency for a riveted joint.

   (ii)  Fusion welded joints must have the flowing E values:

   (A)  Single lap weld is 40%.

   (B)  Double lap weld is 60%.

   (C)  Single butt weld is 60%.

   (D)  Double butt weld is 75%.

   (E)  Forge weld is 70%.

   (F)  Brazed steel and brazed copper is 80%.

   (4)  R equals the inside radius of the weakest course of the shell in inches if the thickness of the shell does not exceed 10% of the radius. The outer radius is used in the equation if the thickness is over 10% of the radius.

   (5)  FS equals the minimum safety factor allowed by this section. The minimum allowable safety factors are as follows:

   (i)  For unfired pressures vessels, except those of lap seam construction, the minimum safety factor is five.

   (ii)  For unfired pressure vessels with longitudinal lap joints the minimum safety factor is 5 1/2.

   (iii)  For unfired pressure vessels with reinstalled or secondhand lap seamed construction the minimum safety factor is six.

   (iv)  For unfired pressure vessels with reinstalled or secondhand butt strap or welded construction the minimum safety factor is 51/2.

   (c)  The ASME Code, section VIII, Division 1 is incorporated as the maximum allowable working pressure for cylindrical unfired pressure vessels subjected to external or collapsing pressure.

   (d)  The formulas in ASME Code, section VIII, divisions 1 and 2 or ASME, section X are incorporated and must be used to calculate the maximum allowable pressure for the head of an existing unfired pressure vessel that was not constructed in accordance with this chapter.

   (e)  The effect of static head must be considered in checking an existing vessel's maximum allowable working pressure.

§ 3a.152. Safety appliances.

   (a)  An unfired pressure vessel must be protected by safety relief devices, and indicating and controlling devices sufficient to insure their safe operation which meet the following requirements:

   (1)  Constructed, located, installed and maintained to prevent the devices from becoming inoperative.

   (2)  Having sufficient relieving capacity to prevent a rise of pressure in the vessel of more than 10% above the maximum allowable working pressure, taking into account the effect of static head.

   (3)  The discharge from safety devices must be carried to a safe place away from the unfired pressure vessel.

   (b)  Safety valves for other than noxious liquids or toxic vapors must be direct spring-loaded type valves, designed with substantial lifting devices so that the disk can be lifted from its seat by the spindle of at least l/8 the diameter of the valve if the pressure of the vessel is at 75% of the safety valve setting.

   (c)  Each safety valve must have clear manufacturer markings that are 1/4-inch, or larger. The markings must contain the following information stamped on the valve, cast on the valve body, or cast on a plate securely fastened to the valve:

   (1)  The name or identifying trade mark of the manufacturer.

   (2)  The pipe size, in inches, of the valve inlet.

   (3)  The pressure, in pounds, at which the valve is set to open.

   (4)  The blow down, in pounds.

   (d)  If the valve inlet is not threaded, the initial diameter of the inlet may not be less than the inside diameter of a standard pipe of the same size.

   (e)  The difference between the opening and closing pressures of a safety valve must be a minimum of 20%.

   (f)  Existing valves bearing ASME stamping different from the requirements in subsection (c) are permitted if the valves have equivalent construction and relieving capacity.

   (g)  Safety valves with a cast iron seat or a disk may not be used.

   (h)  If more than one safety valve is used, the discharge capacity must be the combined capacity of all safety valves.

   (i)  A vessel in which pressure is not generated and is derived from an outside source shall have a safety device connected to the vessel, vessels or system which it protects in a manner to prevent a rise in pressure beyond the maximum allowable pressure.

   (j)  A vessel in which pressure may be generated must have a safety device or devices connected directly to the vessel and in accordance with the following:

   (1)  When the contents of a vessel may cause interference with the operation of the vessel or safety valve when the safety value is directly attached, the safety valve or valves may be connected in a manner to avoid the interference.

   (2)  An escape pipe may be used. The pipe must be full sized and fitted with an open drain to prevent liquid from lodging in the upper part of the safety valve. A valve may not be placed on the escape pipe between the safety valve and the atmosphere.

   (3)  An elbow may be placed on an escape pipe if it is located close to the safety valve outlet or the escape pipe is securely anchored and supported. If two or more safety devices are placed on one connection, the connection must have a cross sectional area at least equal to the combined area of the safety devices' inlets.

   (k)  Every safety valve which is exposed to temperatures of 32°F. or less must have a drain of at least 3/8 inch in diameter at the lowest point where water can collect.

   (l)  A spring in a safety or relief valve in service for pressures 250 psi and less may not be reset for a pressure more than 10% above or 19% below the pressure at which the valve is marked. For pressures higher than 250 psi, the spring may not be reset for any pressure more than 5% above or 50% below the pressure at which the safety or relief valve is marked.

   (m)  Safety valves for compressed air tanks cannot be larger than 3-inch diameter. The valves must be proportioned for the maximum number of cubic feet of free air that may be applied per minute.

   (n)  A rupture disk may be used as a pressure safety device on vessels containing nontoxic gases, when it is designed to fail at not more than the design pressure of the vessel.

   (o)  Safety valves on systems using toxic gases must discharge in accordance with the ASME Code, section VIII, Division 1, 2 or 3.

§ 3a.153. Pipe connections and fittings.

   (a)  The general arrangement of piping must be designed to reduce vibration, expansion and drainage, and provide adequate support at the proper points.

   (b)  The code of construction governs repairs of existing high-pressure/temperature piping systems installed before 1998.

§ 3a.154. Repair and renewal.

   Repairs to fittings and controls must comply with the ASME Code and ASME/CSD1 requirements for installations.

Subchapter H. SPECIAL INSTALLATIONS

§ 3a.161. Modular boilers.

   (a)  A modular boiler as defined in ASME Code, section IV must be installed in accordance with § 3a.36 (relating to clearances). The distance between modules may be reduced to the manufacturer's recommendations if the entire modular boiler system meets the 30-inch clearance requirements.

   (b)  A modular boiler must have only one inlet and one outlet valve, as required by ASME Code, section IV. The boiler controls must comply with ASME Code, section IV and ASME/CSD1.

§ 3a.162. Portable boilers.

   (a)  A portable boiler must meet the requirements of § 3a.21 (relating to stamping).

   (b)  A portable boiler may be mounted in covered trailers if all of the following conditions are met:

   (1)  A 30-inch clearance is provided on both ends of the boiler.

   (2)  The boiler's trailer is provided with chocks and is anchored to prevent movement during operation.

   (3)  The boiler is anchored to the trailer.

   (4)  The trailer provides a means or area to remove boiler tubes.

   (5)  The roof or the ceiling of the trailer provides space to allow proper operation of all valves and appurtenances.

   (c)  The clearance on one side of a boiler mounted in a covered trailer may be reduced to 3 inches if the trailer has access panels for removal of handhole plugs for inspection and maintenance.

   (d)  The user or operator shall notify the Department in writing and obtain written Department approval before a portable boiler is moved and placed in service.

§ 3a.163. Fired coil water heaters and instantaneous water heaters.

   (a)  A fired coil water heaters and instantaneous water heater must be installed in accordance with ASME Code, section IV, articles HLW 700, HLW 800 and HG 614.

   (b)  A storage vessel may be used with a fired coil water heater and instantaneous water heater, if its controls comply with ASME CSD1, and it meets the ASME Code over-pressure protection requirements. The vessel must be ASME Code constructed if the BTU input exceeds 200,000 BTU.

   (c)  Temperature controls must be designed to not exceed 210°F.

§ 3a.164. Storage water heaters.

   (a)  A storage water heater must be installed in accordance with ASME Code, section IV, articles HLW 700 and HLW 800, and comply with safety valve requirements of ASME CSD1.

   (b)  Temperature controls must be designed to not exceed 210°F.

§ 3a.165. Steam/hot water coil storage water heater.

   (a)  The design and construction of a steam/ hot water coil storage water heater must comply with ASME Code, section VIII and the additional control requirements of ASME CSD1.

   (b)  Temperature controls must be designed to not exceed 210°F.

§ 3a.166. Miniature boilers and kitchen equipment.

   (a)  A miniature boiler must be manufactured under the ASME ''S,'' ''H'' or ''M'' Code. A boiler manufactured under ASME ''S'' and ''H'' Code must be stamped with a National Board registration number.

   (b)  Clearance requirements contained in § 3a.36 (relating to clearances) do not govern a miniature boiler or kitchen equipment if all pressure containing parts with appurtenances are visible for inspection.

   (c)  Miniature boiler controls must comply with ASME/CSD1.

   (d)  The sight glass and pressure gauge of a miniature boiler installed in a cabinet must always be visible during operation.

   (e)  Discharge from safety valves must be piped to a safe point.

   (f)  Burners for gas-fired installations must be AGA approved.

§ 3a.167. Hot water/steam heat exchangers.

   (a)  Heater exchangers must be manufactured under the ASME Code.

   (b)  Heat exchangers must have adequate over-pressure protection to protect both systems.

   (c)  Heat exchangers used for domestic hot water supply must have a high temperature limit switch designed not to exceed 210°F.

§ 3a.168. Autoclaves and quick opening vessels.

   (a)  An inspector shall inspect autoclaves and quick opening vessels with close examination of all moving parts, locking devices, pins and interlocking devices, in accordance with ANSI/NB 23.

   (b)  An autoclave and quick opening vessel must have interlocking systems to prevent charging the vessel until all openings and locking devices are fully in place.

   (c)  A pressure-relieving device must be sized in accordance with the data plate for pressure. The capacity must be based on the pressure and pipe size or the total BTU valve of the boiler.

§ 3a.169. Fuel trains and piping systems.

   (a)  The piping of low-pressure steam systems, except PVC materials, must comply with Chapters 10 and 12 of the IMC.

   (b)  The piping of low-pressure hydronic piping systems, except PVC materials, must comply with Chapter 12 of the IMC.

   (c)  The design and installation of high-pressure steam and high temperature hot water piping must comply with ASME B31.1.

   (d)  The repair of high pressure/temperature piping systems installed before 1998 must comply with the code of construction.

   (e)  The installation of fuel trains and associated piping must comply with ASME/CSD1.

§ 3a.170. Swimming pool heaters.

   (a)  A swimming pool heater is an instantaneous water heater. The heater must meet the construction requirements of ASME Code, section IV and the control requirements of ASME/CSD1 except if exempt under § 3a.3(d) (relating to scope).

   (b)  A pool heater may be piped with polyvinyl chloride material rated for the pressure and temperature of the heater after the isolation valves.

§ 3a.171. Locomotive boilers.

   New installations for boilers of locomotives must comply with ASME Code, section I.

[Pa.B. Doc. No. 04-1996. Filed for public inspection November 5, 2004, 9:00 a.m.]



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