Rules & Regulations of the State of Tennessee
Title 0080 - Department of Agriculture
Subtitle 0080-05 - Markets
Chapter 0080-05-07 - Rules and Regulations Pertaining to Anhydrous Ammonia Storage and Equipment Act
Section 0080-05-07-.04 - BULK STORAGE OF ANHYDROUS AMMONIA

(a) Aboveground storage containers with a designed pressure of less than 200 psi for ASME shall be refrigerated to maintain the pressure below the pop off pressure. Refrigeration shall be accomplished as follows:

(a) Aboveground containers of less than 250 psi for ASME and not less than 200 psi for ASME, shall be provided with a shed that extends outward from and above the height of the container, at least 3', and roof shall be constructed of non-flammable, heat reflecting material. In lieu of the shed, a suitable sprinkling system may be installed.

(a) All underground containers shall be buried a minimum of 24" below the surface of the ground. All such containers shall be coated with one coat of red lead and two heavy coats of coal tar or asphalt. Any underground container that is not buried to a depth of 24" below the ground, or any container that is "mounded" over or showing above the earth shall fall under the classification of aboveground installation and must have the necessary protective devices required for such installation.

(b) Containers once installed underground shall not later be reinstalled aboveground or underground, unless they successfully withstand hydrostatic pressure retests at the pressure specified for the original hydrostatic test as required by the code under which constructed, and show no evidence of serious corrosion. Where containers are reinstalled underground, the corrosion resistant coating shall be put in good condition.

(a) Aboveground containers shall be mounted on substantial masonry supports, or structural steel supports on substantial masonry footings. These containers must be supported through a minimum arch of 120' if masonry supports are used. 1/4" insulation shall be placed between the masonry and the tank to prevent corrosion and protect the life of the support. All such containers shall be painted with a heat reflecting paint such as white or aluminum.

(a) All storage containers shall have their relief valves vented vertically and directly upwards to a point at least 15' above the ground. Vent pipe shall not be restricted or smaller in size than the relief valve it vents. All vent pipe shall have a suitable raincap that will allow free discharge of the vapor and prevent the entrance of water, and at the bottom of each vent pipe a small hole shall be cut to allow any moisture that may collect in the vent to escape. If housed in a building or sun-shade, openings shall be provided so that full advantage of a natural ventilation may be obtained. All vent pipes shall be properly guyed.

(a) All underground storage containers having a water capacity in excess of 1,200 gallons, shall have perforated drain tile 6" in diameter under each side of the tank, running parallel to the tank leading into a main drain tile which empties into a catch basin. The catch basin shall have a power driven pump operating automatically to keep water away from the tanks. A hand operated water pump shall be maintained in standby condition. All drain tile shall be at least the depth of the bottom of the container, with the containers resting on firm earth, the tile on two inches of slag, rock, or gravel and covered to a depth of at least 12" with the same material. Where there are more than one tank in the same underground installation, the tile may be arranged to drain the entire installation and not necessarily each tank individually.

(a) All areas occupied by a bulk storage installation belonging to a dealer shall be enclosed by a substantial wire fence. Fencing shall not be installed closer than 5' to any tank. All valves shall be equipped with locking devices. Said storage areas shall have warning signs cautioning against smoking, carelessness, and the presence of unauthorized personnel.

(a) Aboveground containers shall be grounded by an adequate and separate ground. This shall consist of a separate ground rod buried to a depth of 6' and connected to the tank by an approved type heavy cable, attached to the tank by soldering or other approved means for a good electrical bond.

(a) In case of multiple storage facilities, a plan must be provided to easily approach all shut-off valves used for isolating various parts of the storage facilities. This is imperative, otherwise a serious leak under certain weather conditions may blanket out completely the storage area and make approach impossible.

(a) Wherever condensers, pumps, and compressors are used, they shall be manufactured by a reputable concern and recommended by the manufacturer for use with ammonia.

(a) Approved type gas mask with refill charges.

(b) One pair of rubber gloves.

(c) One pair of rubber boots.

(d) One rubber slicker and/or rubber pants and jacket.

Easily accessible shower bath and/or 50 gallon open top drum filled with water.

(e) One pair tight fitting ventless type goggles.

(f) First aid kit.

(g) Fire extinguisher.