WAC 296-826-300 Design, construction and installation

For printing

YOUR RESPONSIBILITY:

To make sure containers and tanks used for storing, distributing, or transporting anhydrous ammonia meet design, construction and installation requirements

CONTAINER LOCATION AND MARKING

WAC 296-826-30005

General specifications

You must

• Locate containers either:
  • -In buildings or parts of the building provided for ammonia storage
    or
  • -Outside, away from densely populated areas.
• Locate containers according to Table 1, Minimum Distances for Container Location.

You must

• Make sure containers are located to meet all of the following:
  • -Away from readily ignitable materials such as weeds, long dry grass, and waste.
  • -So there's no adverse impact on employee health through unnecessary exposure.
  • -At least 50 feet away from dug wells and other sources of potable water.
  • -If the container is a part of a water treatment installation, then this requirement doesn't apply.
• Maintain legibility of all container and valve markings.

WAC 296-826-30010

Specifications for portable DOT containers

IMPORTANT:

This section applies to systems that use cylinders, portable tanks (DOT-51), or "ton containers" (DOT-106A, DOT-110A), constructed according to DOT specifications.

You must

• Locate containers aboveground, never buried below the ground.
• Put containers on firm ground or secure them.
• Guard against settling on the outlet piping by using a flexible connection or a special fitting.
• Protect containers from all of the following:
  • -Ignitable debris
  • -External damage including corrosion
  • -Heat sources, like radiant flames and steam pipes
  • -Moving vehicles.
• Prohibit the use of heat to raise the container pressure.

WAC 296-826-30015

Nonrefrigerated stationary containers

You must

• Construct and test containers according to the Unfired Pressure Vessel Code.
• Make sure the minimum design pressure of the container is 250 psig
• Make sure all containers with a capacity exceeding 250 gallons are constructed to meet one or more of the following:
  • -Stress relieved after fabrication according to the Unfired Pressure Vessel Code
  • -Have stress relieved cold-formed heads
  • -Hot-formed heads

WAC 296-826-30020

Refrigerated storage

You must

• Make sure the minimum design temperature is the same as the refrigerated temperature of the tank.
• Construct and test containers, with a design pressure exceeding 15 psig, according to the Unfired Pressure Vessel Code.
• Select construction materials from those listed from API Standard 620, 4th Edition 2002, Recommended Rules for Design and Construction of Large, Welded Low Pressure Storage Tanks.
• Construct tanks with a design pressure with 15 psig or less according to API Standard 620, 4th Edition, 2002.
• Use ASME Code as a guide in the selection of austenitic steels or nonferrous materials, if used at the design temperature.

WAC 296-826-30025

Systems mounted on trucks, semi-trailers, and trailers

You must

• Construct and test containers, when transported within the state of Washington, according to both of the following:
  • -A minimum design pressure of 250 psig
  • -The Unfired Pressure Vessel Code.
• Construct containers used for interstate transport according to DOT regulations.
• Make sure the shell or head thickness of any container is at least 3/16 of an inch.
• Make sure electrical lighting circuits meet all of the following:
  • -Have suitable over-current protection, such as fuses or automatic circuit breakers.
  • -Are suitably secured, insulated, and protected against physical damage.
  • -Have wiring with sufficient carrying capacity and mechanical strength.
• Use only electric light.

WAC 296-826-30030

Systems mounted on farm trucks or trailers for transporting ammonia

You must

• Construct and test containers, with a design pressure exceeding 15 psig, according to the Unfired Pressure Vessel Code.

WAC 296-826-30035

Systems mounted on farm equipment for ammonia application

You must

• Construct and test containers according to the Unfired Pressure Vessel Code.

WAC 296-826-30040

DOT containers

You must

• Make sure containers meet DOT specifications.

NONREFRIGERATED CONTAINERS

WAC 296-826-30045

Installation

You must

• Provide a minimum distance of 5 feet between aboveground and underground containers that have more than a 1,200 gallon capacity each.
• Protect containers from floating away, in areas with a potential for high flood waters, by providing either:
  • -Secure anchorage
    or
  • -Adequate pier height.
• Follow Tabel 2 for aboveground, nonrefrigerated containers.

You must

• Follow Table 3 for underground, non-refrigerated containers.

WAC 296-826-30050

Reinstallation

You must

• Prohibit the reinstallation of nonrefrigerated , previously installed underground, containers unless they meet both of the following:
  • -Pass a hydrostatic pressure retest using the original pressure specified by the Unfired Pressure Vessel Code under which the tank was constructed
    and

  • -Show no evidence of serious corrosion.
• Maintain a corrosion resistant coating on reinstalled underground containers.

REFRIGERATED STORAGE TANKS

WAC 296-826-30055

Installation

You must

• Support tanks on noncombustible foundations designed for the type of tank.
• Provide protection against flotation or other water damage, where high floodwater might occur.
• Prevent the effects of freezing and consequent frost heaving, in tanks used for product storage at less than 32°F, by providing either support or heat supply.
• Prevent accidental discharge of liquids from spreading into uncontrolled areas by providing, to the area surrounding a refrigerated tank or group of tanks, one of the following:
• -A drainage system provided with at least a one percent slope that terminates in an impounding basin with a capacity as large as the largest tank served
  
or
• -A diked enclosure with a capacity as large as the largest tank served.
• Meet, when using a diked enclosure or an impounding basin in a drainage system, the following requirements:
• -The wall is made of earth, steel, or concrete.   If made of earth, meet both of the following:
• The top is flat and at least 2 feet wide
  

  and

• There's a stable slope consistent with the angle of the earth used
• -Design the wall to be both:
• Liquid tight

  and

• Able to withstand the hydrostatic pressure and the temperature.
• Provide for drainage of rain water, that doesn't permit the release of ammonia, from diked or impounding areas.

• Shallow channels in the ground surface or low curbs of earth can help guide the liquid to these low areas without contacting a large ground area.

WAC 296-826-30060

Reinstallation

You must

• Make sure moved and reinstalled containers of a size to require field fabrication are reconstructed and reinspected to:
  • -Meet the original Unfired Pressure Vessel Code under which the tank was manufactured and do the following according to the same code:
    • A pressure retest
    • Any necessary rerating.