Pesticide and Fertilizer Management Division, Ph: 651-201-6275, Fx: 651-201-6117 FACT SHEET
Anhydrous Ammonia Truck/Nurse Tank Riser Area Pull-Away
Protection - Construction and Design Specification Requirements
TRUCK AND RISER FLOW PROTECTION EXCEPTION: Because of the difﬁculty of employing sufﬁcient
bulkhead protection, riser excess ﬂow valves are an exception.
DEVICES AND FUNCTION OF BULKHEADS
In such cases automatically operating emergency shutoff
Backﬂow check, excess ﬂow, and emergency shutoff valves protected by a bulkhead or shear/weakness ﬁttings must
valves provide ﬂow control protection (FCP) in the event supplement the riser excess ﬂow valves.
of a hose rupture or pull away incident. In the truck unload
area, a backﬂow check valve is required for each liquid
line outlet and a properly sized excess ﬂow valve for each
To afford adequate protection of system piping and FCP
vapor line outlet. Each liquid and vapor riser line outlet
devices, the bulkhead must remain fully intact during a
(nurse tank loading) must be equipped with a properly
pull- away incident. Depending on the direction of the
sized excess ﬂow valve.
pull-away, a truck unload area bulkhead must withstand a
pull of approximately 5,000 to 10,000 pounds in contrast to
FCP devices must be installed in the facility piping so
2,000 to 3,000 pounds for a riser area.
that any break will occur on the side of the hose or swivel
connection. This is where bulkhead pull-away protection
Another consideration in the design of a bulkhead is the
for the truck unloading and riser areas come into play. A
reduction factor. The reduction factor takes into account
bulkhead is deﬁned as the entire above and below ground
some of the construction, environmental, or material
structure that protects system piping and FCP devices. To
speciﬁcation that relates to the construction of a bulkhead,
afford adequate system protection, FCP devices, valving,
and its ability to withstand a pull away. A reduction factor
piping, and other system appurtenances must be positioned
of .66 is used in determining the material speciﬁcations
behind the bulkhead structure.
listed in the Tables 1 through 4.
In accordance with the Americans with Disabilities Act, an alternative form of communication is available upon request. anhydrous amm truck riser.indd
TTY: 1-800-627-3529. MDA is an equal opportunity employer and provider. 05/06
WHEN BULKHEAD PROTECTION MAY NOT TIME TABLE FOR COMPLIANCE
BE REQUIRED The installation of additional ﬂow protection devices and
A bulkhead may not be required when the truck or riser bulkhead protection must be completed within two years of
piping is equipped with suitable weakness or shear ﬁttings the effective date of Minnesota Rules, Part 1513.0200, or by
capable of breaking on the side of the hose or swivel September 2, 1998.
connection. In the event of a pull away incident, the
weakness or shear ﬁttings would only require sufﬁcient For more information, contact the Minnesota Department of
bracing, as speciﬁed by the manufacturer, to maintain the Agriculture at 612/201-6275 or e-mail ekaiser@ mda.state.
condition of the system piping and other FCP devices. mn.us