Locations Where 350-400 psi/NH3 Rated Hydrostatic Relief Valves (Hydrostats) Are Required To Protect Permanently Assigned/Attached Hosing/Lines Between Shut-Off Valves:
- Single nurse tank unit with single hose/line:
- In the nurse tank withdrawal valve.
- Dual nurse tank unit:
- Single hose/line: In nurse tank withdrawal valve.
- Merged hoses/lines: In one nurse tank withdrawal valve provided that the only other shut-off valve is located at the opposite end/hose connection point.
- Crossover hose/line: In nurse tank liquid fill, vapor, or between other pairs of shut-off valves.
- Application/Toolbar Unit:
- The area that includes the withdrawal hose to the discharge side (female side) of the break-away coupling device.
- Any other locations:
- Permanently attached/assigned hose/line in which liquid ammonia can be isolated between shut-off valves.
Though not required, a hydrostat installed in nurse tank withdrawal valve and connections provides an added layer of protection for temporary assigned/attached hosing/lines.
Questions? Contact area NH3 Inspector or St. Paul Office
- Bob Rialson @ (507) 746-4483 Counties: Brown, Cottonwood, Faribault, Jackson, Lac Qui Parle, Lincoln, Lyon, Martin, Murray, Nobles, Pipestone, Redwood, Rock Watonwan, Yellow Medicine.
- Jeff Lorentz @ (320) 223-6547 Counties: Benton, Blue Earth, Carver, Dakota, Dodge, Fillmore, Freeborn, Goodhue, Houston, Isanti, Le Sueur, McLeod, Meeker, Mille Lacs, Morrison, Mower, Nicollet, Olmsted, Renville, Rice, Scott, Sherburne, Sibley, Steele, Wabasha, Waseca, Winona, Wright
- Jim Freilinger @ (320) 243-7382 Counties: Big Stone, Chippewa, Clay, Douglas, Grant, Kandiyohi, Kittson, Mahnomen, Marshall, Norman, Ottertail, Pennington, Polk, Pope, Red Lake, Roseau, Stearns, Stevens, Swift, Traverse, Wilkin
- Ed Kaiser @ (651) 201-6275 St. Paul Office.
