Louisiana Administrative Code › Title 55 - PUBLIC SAFETY › Part V - Fire Protection › Chapter 50 - Boiler Construction, Maintenance, Inspection and General Use › Subchapter C - Existing Installations- Power Boilers › Section V-5042 - Safety Relief Valve Requirements for Hot Water Heating and Hot Water Supply Boilers

Current through Register Vol. 50, No. 6, June 20, 2024
A. Each hot
				  water heating and hot water supply boiler shall have at least one ASME/National
				  Board stamped and certified safety relief valve set to relieve at or below the
				  maximum allowable working pressure of the boiler. Each hot water supply boiler
				  shall have at least one ASME/National Board stamped and certified safety relief
				  valve of the automatic reseating type set to relieve at or below maximum
				  allowable working pressure of the boiler. Safety relief valves ASME/National
				  Board stamped and certified as to capacity shall have pop action when tested by
				  steam. When more than one safety relief valve is used on either a hot water
				  heating or hot water supply boiler, the additional valve or valves shall be
				  ASME/National Board stamped and certified and may be set within a range not to
				  exceed 6 psig above the maximum allowable working pressure of the boiler up to
				  and including 60 psig and 5 percent for those having a maximum allowable
				  working pressure exceeding 60 psig. Safety relief valves shall be spring
				  loaded. Safety relief valves shall be so arranged that they cannot be reset at
				  a higher pressure than the maximum indicated in this Paragraph.
B. No materials liable to fail due to
				  deterioration or vulcanization when subject to saturated steam temperature
				  corresponding to capacity test pressure shall be used for any part.
C. No safety relief valve shall be smaller
				  than 3/4 inch nor larger than 4-1/2 inch standard pipe size, except that
				  boilers having a heat input not greater than 15,000 BTU per hour may be
				  equipped with a safety relief valve of 2 inch standard pipe size. The inlet
				  opening shall have an inside diameter approximately equal to, or greater than,
				  the seat diameter. In no case shall the minimum opening through any part of the
				  valve be less than 1/4 inch in diameter or its equivalent area.
D. The required steam relieving capacity, in
				  pounds per hour, of the pressure relieving device or devices on a boiler shall
				  be the greater of that determined by dividing the maximum output in BTU at the
				  boiler nozzle obtained by the firing of any fuel for which the unit is
				  installed by 1,000 or shall be determined on the basis of pounds of steam
				  generated per hour per square foot of boiler heating surface as given in Table
				  EHB-6. In many cases, a greater relieving capacity of valves will have to be
				  provided than the minimum specified by these rules.
E. When operating conditions are changed, or
				  additional boiler heating surface is installed the valve capacity shall be
				  increased, if necessary, to meet the new conditions. The additional valves
				  required because of changed conditions may be installed on the outlet piping
				  provided there is no intervening valve.
F. Safety relief valve capacity for each
				  boiler shall be such that, with the fuel burning equipment installed and
				  operated at maximum capacity, the pressure cannot rise more than 10 percent
				  above the maximum allowable working pressure. When more than one safety relief
				  valve is used, the over pressure shall be limited to 10 percent above the set
				  pressure of the highest set value allowed.
G. If there is any doubt as to the capacity
				  of the safety relief valve, an accumulation test shall be run (see ASME Code,
				  Section VI, Recommended Rules for Care and Operation of Heating
				  Boilers).
H. No valve of any
				  description shall be placed between the safety relief valve and the boiler, nor
				  on the discharge pipe between the safety relief valve and the atmosphere. The
				  discharge pipe shall be not less than the diameter of the safety relief valve
				  outlet and fitted with an open drain to prevent water lodging in the upper part
				  of the safety relief valve or in the discharge pipe. When an elbow is placed on
				  the safety relief valve discharge pipe, it shall be located close to the safety
				  relief valve outlet or the discharge pipe shall be securely anchored and
				  supported. All safety relief valve discharges shall be so located or piped as
				  not to endanger persons working in the area.
AUTHORITY NOTE:
					 Promulgated in accordance with
					 R.S.
					 23:531 and
					 R.S.
					 51:1424.