Current through Register Vol. 49, No. 18, September 16, 2024
(2) Heating Boilers, Water Heaters, Pool
Heaters, and Fired Jacketed Steam Kettles, Installed or Contracted for Prior to
November 12, 1986.
(A) The service life of
any boiler, water heater, pool heater, or fired jacketed steam kettle of
standard construction shall be unlimited, provided:
1. It meets the inspection requirements of
11 CSR
40-2.022; and
2. All controls and safety devices required
by American Society of Mechanical Engineers (ASME) Section IV Code for heating
boilers and water heaters and ASME Section VIII, Division 1 Code for fired
jacketed steam kettles and these rules shall be installed and
operable.
(B) The
service life of any heating boiler, water heater, pool heater, or fired
jacketed steam kettle of nonstandard construction shall be thirty (30) years.
The thirty (30)-year life may be extended with the chief inspector's approval
and compliance with the following requirements:
1. The operating pressure cannot exceed the
maximum allowable working pressure (MAWP). The boiler, water heater, or fired
jacketed steam kettle MAWP shall be calculated in accordance with the ASME Code
or the requirements of the original code of construction. Objects manufactured
to a standard other than the ASME Code shall be evaluated in accordance with
the "state special" requirements in accordance with 11 CSR 402.064. The
allowable stress shall be no greater than eleven thousand pounds per square
inch (11,000 psi). The joint efficiency shall be in accordance with the
appropriate edition and addenda of the ASME Code, most applicable for the type
of construction. The MAWP of any cast iron boiler shall not be greater than
fifteen (15) psi steam or thirty (30) psi water pressure;
2. A pressure test shall be conducted every
four (4) years at normal operating pressure not to exceed the MAWP of the
object. The test pressure shall be held for at least thirty (30) minutes
without evidence of leakage and documented to the satisfaction of the
inspector. The inspector need not witness the test. The test may be an
operational test. If the object exhibits any signs of leakage, it shall be
repaired prior to restoring the object to service;
3. All safety devices and controls required
by the applicable ASME Code and these rules shall be installed and
operable.
(3)
Heating Boilers, Water Heaters, Pool Heaters, and Fired Jacketed Steam Kettles
Contracted after November 12, 1986.
(A) New
and second-hand heating boilers, water heaters, and pool heaters shall be
designed, fabricated, and installed to the requirements of ASME Section IV Code
and these rules. New and second-hand fired jacketed steam kettles shall be
designed, fabricated, and installed to the requirements of ASME Section VIII,
Division 1 Code and these rules.
(B) Reinstalled boilers may be of standard or
nonstandard construction and shall be installed in accordance with the
requirements of the ASME Code and these rules, non-standard heating boilers
cannot be reinstalled in Missouri except when relocating from one location to
another location within Missouri. Approval of the chief inspector shall be
obtained prior to reinstalling a nonstandard boiler.
(4) General Requirements for Heating Boilers,
Water Heaters, Pool Heaters, and Fired Jacketed Steam Kettles.
(A) Heating boilers, water heaters, pool
heaters, and fired jacketed steam kettles shall not be operated for a purpose
not originally intended by the manufacturer unless approved by the board (i.e.,
potable water heaters may not be operated as a steam or hot water heating
boiler).
(B) Heating boilers, water
heaters, pool heaters, and fired jacketed steam kettles must be installed in
accordance with the manufacturer's instructions and these rules, unless
otherwise approved by the chief inspector.
(C) Heating boilers with heat input less than
12,500,000 British thermal units per hour (Btu/hr) contracted after January 1,
2004, shall meet the requirements of ASME CSD-1. Fuel gas piping for these
boilers shall comply with the requirements of National Fire Protection
Association (NFPA) 54. Oil burning equipment shall comply with the requirements
of NFPA 31. Single unit boilers with heat input greater than or equal to
12,500,000 Btu/hr, boilers with pulverized fuel systems, and waste heat boilers
shall meet the requirements of NFPA 85. All controls required by NFPA 85 for
automatically fired boilers shall be installed in accordance with the
installation requirements of ASME CSD-1. Existing installations are exempt from
these rules except that any modification or replacements to the controls after
January 1, 2004, shall meet the requirements for new installations. Boilers
installed on or after January 1, 2010, must be in accordance with the National
Board Inspection Code, Part 1, and these rules.
(D) All safety and safety relief valve
outlets shall be piped to a safe discharge. There shall be no valves on the
outlet piping or between the boiler and the safety or safety relief valve
inlet. The end of all discharge piping shall be visible to the operator when
piped into a drain. Drains on safety or safety relief valve bodies shall remain
open at all times. Safety or safety relief valve inlet and outlets shall not be
reduced. Weighted lever safety valves are prohibited. Safety valves with either
the seat or disk of cast iron are prohibited. The minimum valve capacity shall
be in accordance with ASME Section IV Code for heating boilers and hot water
heaters and Appendix 19 of ASME Section VIII, Division 1 Code for fired
jacketed steam kettles. Alternatively, the relieving capacity for heating
boilers may be determined based on the burner output rating or by multiplying
the heating surface in square feet by the applicable value in the following
table:
Minimum Pounds of Steam Per Hour Per Square Foot of
Heating Surface
Fire Tube Boiler
|
Water Tube Boiler
|
Boiler |
Hand fired |
5 |
6 |
Stoker fired |
7 |
9 |
Oil, gas, pulverized fuel fired |
8 |
10 |
Waterwall |
Hand fired |
8 |
8 |
Stoker fired |
10 |
10 |
Oil, gas, pulverized fuel fired |
14 |
16 |
When a boiler is fired only by a gas having a heat value not
in excess of two hundred (200) Btu/cubic feet (cu. ft.), the minimum safety or
safety relief valve capacity may be based on the value given for hand fired
boilers. The minimum safety or safety relief valve capacity for electric
boilers shall be three and one-half (3.5) pounds per hour per kilowatt
input.
(E) Each heating
boiler, water heater, and fired jacketed steam kettle shall be safely
supported. There shall be no excessive vibration in either the object or the
connecting piping.
(F) All existing
heating boilers, water heaters, pool heaters, and fired jacketed steam kettles
shall have adequate clearance on all sides and top to facilitate repair,
maintenance, and inspection. Heating boilers, water heaters, pool heaters, and
fired jacketed steam kettles, installed or reinstalled on or after January 1,
2010, shall meet the following requirements:
1. There shall be at least thirty-six inches
(36") of clearance on each side of the boiler. Boilers in battery shall not be
installed any closer than forty-eight inches (48"). The front and rear of the
boiler shall not be located nearer than thirty-six inches (36") from any wall
or structure;
2. Boilers shall be
installed to allow for removal and installation of tubes;
3. Boilers with top-opening manholes shall
have at least eighty-four inches (84") of unobstructed clearance above the
manhole to the ceiling of the boiler room;
4. Boilers without top-opening manholes shall
have at least thirty-six inches (36") clearance from the top of the
boiler;
5. Boilers with bottom
openings used for inspection or maintenance shall have at least twelve inches
(12") of unobstructed clearance; and
6. Modular heating boilers that require
individual units to be set side by side, front to back, or by stacking may
provide clearances in accordance with the manufacturer's recommendations with
the approval of the chief inspector.
7. Note: Alternatively, clearances in
accordance with the manufacturer's recommendations are subject to the approval
of the chief inspector.
(G) All rooms containing heating boilers,
water heaters, and fired jacketed steam kettles with a combined capacity over
one (1) million Btu/hr and over five hundred (500) square feet floor area shall
have at least two (2) exits remotely located from each other.
(H) Ladders and runways shall be provided
between or over the top of boilers installed or reinstalled on or after January
1, 2010, that are more than eight feet (8') above the operating floor to afford
accessibility for normal operation, maintenance, and inspection. These ladders
and runways must be built and installed in accordance with the National Board
Inspection Code, Part 1.
(I)
Combustion air-The boiler room shall have an adequate air supply to permit
clean, safe combustion, minimize soot formation, and maintain a minimum of
nineteen and one-half percent (19.5%) oxygen in the air of the boiler room. The
combustion and ventilation air shall be supplied by an unobstructed opening or
by power ventilation or fans.
1. Unobstructed
air openings shall be sized on the basis of one (1) sq. in. (6.50 sq. mm) free
area per two thousand British thermal units per hour (2,000 Btu/hr) (five
hundred eighty-six watts per hour (586 W/hr)) maximum fuel input of the
combined burners located in the boiler room or as specified in the National
Fire Protection Association (NFPA) standards for oil and gas burning
installations for the particular job conditions. The boiler room air supply
openings shall be kept clear at all times.
2. Power ventilators or fans shall be sized
on the basis of 0.2 cfm (.0057 cubic meters per minute) for each one thousand
British units per hour (1,000 Btu/hr) (two hundred ninety-three watts per hour
(293 W/hr)) of maximum fuel input for the combination burners of all boilers
located in the boiler room. Additional capacity shall be required for any other
fuel burning equipment in the boiler room.
3. When power ventilators or fans are used to
supply combustion air, they shall be installed with interlock devices so that
the burners will not operate without an adequate number of ventilators/fans in
operation.
4. When combustion air
is supplied to the boiler by an independent duct, with or without the
employment of power ventilators or fans, the duct shall be sized and installed
in accordance with the manufacturer's recommendations. However, ventilation of
the boiler room must still be considered.
5. Care should be taken to ensure that steam
and water lines are not routed across combustion air openings, where freezing
may occur.
6. Opening boiler room
door(s) and/or window(s) is unacceptable for supplying combustion
air.
(J) Controls-
1. Oil-fired, gas-fired, and electrically
heated heating boilers, water heaters, pool heaters, and fired jacketed steam
kettles shall be equipped with suitable primary (flame safeguard) safety
controls, limit switches, and burners or electric elements that are labeled and
listed by a nationally or internationally recognized standard.
2. All controls and devices shall be
installed in accordance with the manufacturer's recommendations, and/or
industry standards, as applicable.
3. All automatically fired heating boilers,
water heaters, pool heaters, and fired jacketed steam kettles shall have a
disconnecting means capable of being locked in the open position and shall be
installed at an accessible location in the same room as the object. This
disconnect means shall disconnect all sources of potential from the
object.
4. A manually operated
remote shutdown switch or circuit breaker shall be located just outside the
entrance door of the room the object is located in and be marked for easy
identification. Consideration should be given to the type and location of the
switch to safeguard against tampering. If the entrance door is on the building
exterior, the switch should be located just inside the door. If there is more
than one (1) door to the room, there should be a switch located at each door.
The emergency switch must be installed in accordance with the manufacturer's
instructions or a nationally recognized standard and must cause a safety
shutdown and lockout.
(K) Each gas-fired water heater contracted
after January 1, 2010, must be certified to the American National Standard/CSA
Standard for Gas Water Heaters, Volume III (ANSI Z21.10.3 CSA 4.3) and must
bear a label as proof of this certification.
(L) Each gas-fired pool heater contracted
after January 1, 2010, must meet one (1) of the following-
1. Be certified to the American National
Standard/CSA Standard For Gas-Fired Pool Heaters, (ANSI Z21.56 CSA 4.7) and
bear the label as proof of this certification; or
2. Commercial pool heaters applications that
do not have one hundred percent (100%) of pool loop water flow circulating
through the pool heater may be certified to the American National Standard/CSA
Standard for Gas Water Heaters, Volume III (ANSI Z21.10.3 CSA 4.3) and must
bear a label as proof of this certification, provided the unit must bear a
label from the manufacturer as evidence that the water heater has been approved
for commercial pool heating applications when installed per the manufacturer's
instructions. Additionally, the manufacturer must provide additional listed
temperature controls that will limit the water temperature delivered to the
pool from exceeding one hundred eight degrees Fahrenheit (108
oF) with details for the installation of
these controls.
(M) The
Code nameplates shall remain readily accessible at all times. Loose or missing
nameplates shall be replaced or reattached as provided for in the
National Board Inspection Code.
(N) Rental heating boilers, water heaters,
and fired jacketed steam kettles, used for temporary service, shall meet all of
the requirements of these rules. The internal inspection, required by
11 CSR
40-2.022, may be waived by the inspector, based on
documentation that a national board-commissioned inspector has evaluated the
internal surfaces of the object within the past twelve (12) months and found
the object acceptable for use. An external, in-operation inspection shall be
the basis for the inspection certificate. The inspection certificate shall
expire no later than twenty-four (24) months from the date of the last internal
inspection.
*Original authority: 650.215, RSMo 1984, amended 1990,
1993, 1995.