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Emergency Vents
One Year Manufacturer Warranty

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Morrison Brothers 244OM Emergency Vents

2 in. to 8 in. MNPT

Ships From Manufacturer

Select Model & Quantity:

Model # Description Price Qty
244OM-0020 AV 2 in. MNPT, 8oz/sq.in., Brass - for General Use, with O-Ring $70.20
244OM-0050 AV 3 in. MNPT, 8oz/sq.in., for General Use, with O-Ring $89.67
244OM-0060 AV 3 in. MNPT, 16oz/sq.in., for General Use, with O-Ring $95.81
244OM-0100 AV 4 in. MNPT, 8oz/sq.in., for General Use, with O-Ring $106.24
244OM-0170 AV 4 in. MNPT, 16oz/sq.in., for General Use, with O-Ring $118.86
244OM-0800 AV 5 in. MNPT, 8 oz/sq. in., for General Use, with O-Ring $151.15
244OM-0200 AV 6 in. MNPT, 8oz/sq.in., for General Use, with O-Ring $162.93
244OM-0400 AV 6 in. MNPT, 16oz/sq.in., for General Use, with O-Ring $202.38
244OM-0600 AV 8 in. MNPT, 8oz/sq.in., for General Use, with O-Ring $266.23
244OM-0700 AV 8 in. MNPT, 16oz/sq.in., for General Use, with O-Ring $332.48
244OM-0060AVEVR 3 in. MNPT 16oz/sq.in. with O-Ring, EVR Approved $95.81
244OM-0170AVEVR 4 in. MNPT 16oz/sq.in. with O-Ring, EVR Approved $118.86
244OM-0200AVEVR 6 in. MNPT 8oz/sq.in. with O-Ring, EVR Approved $171.07
244OM-0400AVEVR 6 in. MNPT 16oz/sq.in. with O-Ring, EVR Approved $212.49
244OM-0600AVEVR 8 in. MNPT 8oz/sq.in. with O-Ring, EVR Approved $279.54
244OM-0700AVEVR 8 in. MNPT 16oz/sq.in. with O-Ring, EVR Approved $349.70
244OM-0900 AV 5 in. MNPT 16 oz. with O-Ring $186.86
244OM-0900AVEVR 5 in. MNPT 16 oz. with O-Ring, EVR Approved $196.21
244OMA0030AVEVR 2 in. MNPT 16oz/sq.in. Aluminum Body with O-Ring, EVR Approved $83.75
244OMAS030AVEVR 2 in. MNPT 16oz/sq.in. with O-Ring, EVR Approved $92.74
244OMB0020 AV 2 in. MNPT 8oz/sq.in. BSP Threads, Brass, with O-Ring $70.20
244OMB0100 AV 4 in. MNPT 8oz/sq.in. BSP Threads, with O-Ring $106.24
244OMB0170 AV 4 in. MNPT 16oz/sq.in. BSP Threads, with O-Ring $118.86
244OMBS0020 AV 2 in. MNPT 8oz/sq.in. BSP Threads, with O-Ring, with Screen $79.20
244OMBSP0050 AV 3 in. MNPT 8oz/sq.in. BSP Male Thread, with O-Ring $89.69
244OMBSP0200 AV 6 in. MNPT 8oz/sq.in. BSP Threads, with O-Ring $162.93
244OMBSP0400 AV 6 in. MNPT 16oz/sq.in. BSP Threads, with O-Ring $202.38
244OMBSP0600 AV 8 in. MNPT 8oz/sq.in. BSP Threads, with O-Ring $266.23
244OMS0020 AV 2 in. MNPT 8oz/sq.in. with O-Ring, with Screen $79.20
244OMS0050 AV 3 in. MNPT 8oz/sq.in. with O-Ring, with Screen $117.04
244OMS0060 AV 3 in. MNPT 16oz/sq.in. with O-Ring, with Screen $123.19
244OMS0060AVEVR 3 in. MNPT 16oz/sq.in. with O-Ring, with Screen, EVR Approved $123.19
244OMS0100 AV 4 in. MNPT 8oz/sq.in. with O-Ring, with Screen $135.11
244OMS0170 AV 4 in. MNPT 16oz/sq.in. with O-Ring, with Screen $182.81
244OMS0170AVEVR 4 in. MNPT 16oz/sq.in. with O-Ring, with Screen, EVR Approved $147.43
244OMS0200 AV 6 in. MNPT 8oz/sq.in. with O-Ring, with Screen $205.15
244OMS0200AVEVR 6 in. MNPT 8oz/sq.in. with Screen, EVR Approved $202.01
244OMS0400 AV 6 in. MNPT 16oz/sq.in. with O-Ring, with Screen $245.80
244OMS0400AVEVR 6 in. MNPT 16oz/sq.in. O-Ring, with Screen, EVR Approved $243.44
244OMS0800 AV 5 in. MNPT 8oz/sq.in. BSP Threads, with O-Ring, with Screen $164.26
244OMS0900 AV 5 in. MNPT 16oz/sq.in. BSP Threads, with O-Ring, with Screen $209.48
244OMS0900AVEVR 5 in. MNPT 16oz/sq.in. BSP Threads, with O-Ring, with Screen, EVR Approved $218.82
244OMSB0100 AV 4 in. MNPT 8oz/sq.in. BSP Threads, with O-Ring, with Screen $135.11
244OMSB0200 AV 6 in. MNPT 8oz/sq.in. BSP Threads, with O-Ring, with Screen $205.15
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Morrison Brothers 244OM Emergency Vents
The 244 Series Emergency Vent (pressure relief only) is used on aboveground storage tanks, as a code requirement, to help prevent the tank from becoming over-pressurized and possibly rupturing if ever exposed to fire. The vent must be used in conjunction with a normal vent. Correct application of this vent requires proper vent size and selection for the tank system in order to meet the specific venting capacity requirements. The new design increases protection against weather, improves manufacturability and helps limit and control dust accumulation.
Fig Suffix Size Description Weight
244OM 0020 AV 2" 8oz/sq.in. Emergency Vent - Male Thread - Brass - w/O-Ring - UL & ULC Listed 1
244OM 0050 AV 3" 8oz/sq.in. Emergency Vent - Male Thread - w/O-Ring, UL & ULC Listed 7
244OM 0060 AV 3" 16oz/sq.in. Emergency Vent - Male Thread - w/O-Ring, UL & ULC Listed 11
244OM 0100 AV 4" 8oz/sq.in. Emergency Vent - Male Thread - w/O-Ring, UL & ULC Listed 10
244OM 0170 AV 4" 16oz/sq.in. Emergency Vent - Male Thread - w/O-Ring, UL & ULC Listed 19
244OM 0800 AV 5" 8 oz/sq. in. Emergency Vent - Male Threaded w/O-Ring - UL&ULC Listed 15
244OM 0200 AV 6" 8oz/sq.in. Emergency Vent - Male Thread - w/O-Ring, UL & ULC Listed 20
244OM 0400 AV 6" 16oz/sq.in. Emergency Vent - Male Thread - w/O-Ring, UL & ULC Listed 37
244OM 0600 AV 8" 8oz/sq.in. Emergency Vent - Male Thread - w/O-Ring, UL & ULC Listed 34
244OM 0700 AV 8" 16oz/sq.in. Emergency Vent - Male Thread - w/O-Ring, UL & ULC Listed 63
WARNING: DO NOT FILL OR UNLOAD FUEL FROM A STORAGE TANK UNLESS IT IS CERTAIN THAT THE TANK VENTS WILL OPERATE PROPERLY. Morrison tank vents are designed only for use on shop fabricated atmospheric tanks which have been built and tested in accordance with UL 142, NFPA 30 & 30A, and API 650 and in accordance with all applicable local, state, and federal laws. In normal operation, dust and debris can accumulate in vent openings and block air passages. Certain atmospheric conditions such as a sudden drop in temperature, below freezing temperatures, and freezing rain can cause moisture to enter the vent and freeze which can restrict internal movement of vent mechanisms and block air passages. All storage tank vent air passages must be completely free of restriction and all vent mechanisms must have free movement in order to insure proper operation. Any restriction of air flow can cause excessive pressure or vacuum to build up in the storage tank, which can result in structural damage to the tank, fuel spillage, property damage, fire, injury, and death. Monthly inspection, and immediate inspection during freezing conditions, by someone familiar with the proper operation of storage tank vents, is required to insure venting devices are functioning properly before filling or unloading a tank.