§ 14-12-60. General requirements.


Latest version.
  • A.

    Inspections generally. All boilers and unfired pressure vessels, unless otherwise exempt by these rules and regulations and which are subject to regular inspection as provided for in section 14-12-24, shall be prepared for such inspection, or hydrostatic tests whenever necessary or by the owner or user when notified by the chief inspector, deputy inspector or special inspector.

    The owner or user shall prepare each boiler or unfired pressure vessel for internal inspection and shall prepare for and apply the hydrostatic test whenever necessary, on the date specified by the chief inspector, deputy inspector or special inspector, which date shall not be less than seven days after the date of notification.

    B.

    Preparation for internal inspection. The owner or user shall prepare a boiler for internal inspection in the following manner:

    1.

    Water shall be drawn off and the boiler thoroughly washed.

    2.

    All manhole and handhole plates, wash-out plugs and plugs in water column connection shall be removed, the furnace and combustion chambers thoroughly cooled and cleansed.

    3.

    All grates of internally fired boilers shall be removed.

    4.

    At each annual inspection, brick work shall be removed as required by the inspector in order to determine the condition of the boiler, headers, furnace, supports or other parts.

    5.

    The steam gauge shall be removed for testing.

    6.

    Any leakage of steam or hot water into the boiler shall be cut off by disconnecting the pipe or valve at the most convenient point.

    Unfired pressure vessels shall be prepared for inspection to the extent deemed necessary by the inspector.

    C.

    Improper preparation for inspection. If a boiler or unfired pressure vessel has not been properly prepared for an internal inspection or the owner or user fails to comply with the requirements for hydrostatic tests as set forth in these rules, the inspector may decline to make the inspection or test and the certificate of inspection shall be withheld until the owner or user complies with the requirements.

    D.

    Removal of covering to permit inspection. If the boiler or unfired pressure vessel is jacketed so that the longitudinal seams of shells, drums or domes cannot be seen, enough of the jacketing, setting wall or other form of casing or housing shall be removed so that the size of the rivets, pitch of the rivets and other data necessary to determine the safety of the boiler or unfired pressure vessel may be obtained, provided such information cannot be determined by other means.

    E.

    Lap seam cracks. The shell or drum of a boiler in which a lap seam crack is discovered along a longitudinal riveted joint shall be immediately discontinued from use. If the boiler is not more than 15 years of age, a complete new course of the original thickness may be installed at the discretion of the inspector (and after approval by the chief inspector). Patching is prohibited. (By "lap seam crack" is meant the typical crack frequently found in lap seams, extending parallel to the longitudinal joint and located either between or adjacent to rivet holes.)

    F.

    Hydrostatic pressure tests. A hydrostatic pressure test, when applied to boilers or unfired pressure vessels of riveted or welded construction, except locomotive boilers, shall not exceed 1½ times the maximum allowable working pressure. Hydrostatic pressure applied to locomotive boilers shall not exceed 1¼ times the maximum allowable working pressure. During the hydrostatic pressure test, the safety valve or valves shall be removed or each valve disc shall be held down by means of a testing clamp and not by applying additional load to the spring with the compression screw. It is suggested that the minimum temperature of the water used to apply a hydrostatic test be not less than 70 degrees Fahrenheit but the maximum temperature shall not exceed 160 degrees Fahrenheit.

    Note: When a hydrostatic test is to be applied to existing installations, the pressure shall be as follows:

    1.

    For all cases involving the question of tightness, the pressures shall be equal to the release pressure of the safety valve or valves having the lowest release setting.

    2.

    For all cases involving the question of safety, the pressure shall be equal to 1½ times the maximum allowable working pressure, except for locomotive boilers, in which case it shall be 1¼ times the maximum allowable working pressure.

    G.

    Low water fuel cut-offs. All automatically-fired steam or vapor boilers shall be equipped with an automatic low-water fuel cut-off and water feeding device so constructed that the water inlet valve cannot feed water into the boiler through the float chamber, and so located as to automatically cut off the fuel supply and/or supply requisite feedwater when the surface of the water falls to the lowest safe water line. This point should be not lower than the bottom of the water glass.

    Such a fuel or feedwater control device may be attached direct to a boiler or to the tapped openings provided for attaching a water glass direct to a boiler, provided that such connections from the boiler are nonferrous tees or Ys not less than one-half-inch pipe size between the boiler and the water glass so that the water glass is attached direct and as close as possible to the boilers; the straightway tapping of the Y or tee to take the water glass fittings, the side outlet of the Y or the tee to take the fuel cut-off or waterfeeding device. The ends of all nipples shall be reamed to full size diameter.

    Designs embodying a float and float bowl shall have a vertical straightway drainpipe at the lowest point in the water equalizing pipe connections by which the bowl and the equalizing pipe can be flushed and the device tested.

    H.

    Safety appliances. No person shall remove or tamper with any safety appliances prescribed by these rules except for the purpose of making repairs. The resetting of safety appliances shall be done in the presence of an authorized inspector.

    I.

    Blow-off tanks. Blow-off piping from a power boiler or a miniature boiler shall not discharge directly into a sewer. A blow-off tank shall be used where conditions do not provide an adequate and safe open discharge.

    Blow-off tanks hereafter installed, if of metal, shall have a plate thickness of not less than 5/16 inch and shall be designed for a minimum working pressure of 50 pounds per square inch gauge.

    The outlet from the blow-off tank shall be twice the area of the inlet pipe and made to extend internally within eight inches from the bottom of the tank.

    A vent pipe at least four times the area of the inlet pipe shall lead to the outer atmosphere.

    Vents shall be as direct as possible to the outer air and discharge at a safe location. There shall be no valve or other possible obstructions, such as water pockets, between the tank and the discharge end of the vent pipe.

    All pipe connections between the tank and the boiler shall be as direct as possible and shall conform to Paragraph P-229, A.S.M.E. Boiler Construction Code.

    For convenience in cleaning the tank, a manhole or an access opening shall be provided.

    Where a blow-off tank is not vented as specified above, it shall be constructed for a pressure equal to that allowed on the boiler to which it is attached or shall be equipped with a safety valve or valves of sufficient capacity to prevent the pressure from exceeding the safe working pressure of the tank.

    As an alternate to the above, blow-off facilities may conform to the provisions set forth in the pamphlet titled, "Boiler Blow-Off Equipment," published by the National Board of Boiler and Pressure Vessel Inspectors, whose address is 1155 N. High St., Columbus, Ohio.

    J.

    Location of blow-offs. The discharge of safety valves, blow-off pipes and other outlets shall be located so as to prevent injury to personnel.

    K.

    Pressure reducing values. Where pressure reducing valves are used, one or more relief or safety valves shall be provided on the low pressure side of the reducing valve in case the piping or equipment on the low pressure side does not meet the requirements for the full initial pressure. The relief or safety valves shall be located adjoining to or as close as possible to the reducing valve. Proper protection shall be provided to prevent injury or damage caused by the escaping steam from the discharge or relief or safety valves if vented to the atmosphere. The combined discharge capacity of the relief valves shall be such that the pressure rating of the lower pressure piping or equipment shall not be exceeded in case the reducing valve sticks open.

    The use of hand-controlled by-passes around reducing valves is permissible. The by-pass, if used around a reducing valve, shall not be greater in capacity than the reducing valve unless the piping or equipment is adequately protected by relief valves or meets the requirements of the high pressure system.

    It is mandatory that a pressure gauge be installed on the low pressure side of a reducing valve.

    L.

    Electric steam generators. All electric steam generators shall be grounded in accordance with the city electrical code.

    A suitable screen or guard shall be provided around high tension bushings and a sign posted warning of high voltage. This screen or guard shall be so located that it will be impossible for anyone working around the generator to accidentally come in contact with the high tension circuits. When adjusting safety valves, the power circuit to the generator shall be open. The generator may be under steam pressure, but the power line shall be open while the operator is making the necessary adjustments.

    Each kw of electrical energy consumed by an electric steam generator operating at maximum rating shall be considered the equivalent of one square foot of heating surface of a fire tube boiler when determining the required amount of safety valve capacity.

    M.

    Major repairs. Where a major repair is necessary, an inspector shall be called for consultation and advice as to the best method of making such repair. After such repair is made it shall be subject to the approval of the inspector. Repairs to all boilers and unfired pressure vessels and their appurtenances, shall conform as nearly as practicable to the requirements of the National Board of Boiler and Pressure Vessel Inspectors.

    N.

    Repairs by fusion welding. When repairs are to be made wherein fusion welding is to be used, permission shall be obtained from the chief inspector, a deputy inspector or a special inspector and the welding shall be done in accordance with the rules recommended by the National Board of Boiler and Pressure Vessel Inspectors.

    O.

    Riveted patches. In applying riveted patches, the design of the patch and method of installation shall be in accordance with the rules for riveted patches recommended by the National Board of Boiler and Pressure Vessel Inspectors.

    P.

    Boiler room and clearance. When boilers are replaced or new boilers installed in either existing or new buildings, a minimum height of at least three feet shall be provided between the top of the boiler proper and the ceiling.

    All boilers shall be so located that two feet clearance around the boiler shall be provided for the proper operations of the boiler and its appurtenances, for the inspection of all surfaces, tubes, water walls, economizer, piping, valves and other equipment and for their necessary maintenance and repair.

    Every boiler hereafter installed in a building other than an industrial building, shall be located in a separate room or compartment and when not otherwise provided, shall be enclosed by fire walls or partitions as approved with floor and ceiling of fire resistant construction.

    Boiler and machinery rooms shall have proper ventilation, natural or mechanical, to insure adequate supply of fresh air to the boilers for proper combustion.

    When machinery emptying poisonous or noxious gases is located or operated in such rooms special precautions shall be provided for the safety of the attendants and occupants of the building.

    Q.

    Shop inspections. Any new power boiler being constructed for installation in the city shall be shop inspected in accordance with the provisions of the applicable section of the A.S.M.E. Boiler Code and shall be stamped A.S.M.E. and National Board. This shall not apply to low pressure heating boilers where shop inspection is not required by the A.S.M.E. Boiler Construction Code.

    Inspections made at the request of a boiler or tank manufacturer by the chief inspector or any deputy inspector shall be charged for at the rate of $25.00 for one-half day and $55.00 for one day plus all expenses, to include traveling, hotel and incidentals. This charge shall not void the regular charge or fee for inspection or certificate when the boiler is installed.

    R.

    Inspection of secondhand equipment. Charges for inspection of secondhand equipment shall be at the rate provided for in subsection Q of this section for shop inspections.

    S.

    Conditions not covered by rules. In any condition not covered by these rules, the A.S.M.E. Code for new installations shall apply.

(Code 1967, § 45-90; Code 1985, § 42-95)