Liquid Level Gauging Devices

Section 215 Section 215.70  Liquid Level Gauging Devices a)         Each container, except those filled by weight, shall be equipped with an approved liquid level gauging device. b)         Each container or system covered in Sections 215.85, 215.110, and 215.115 shall be fitted with a liquid level gauge indicating the maximum level to which the container may be filled with liquid anhydrous ammonia at temperatures between 20°F and 100°F, except on containers provided with fixed maximum level indicators, such as fixed length dip tubes or containers that are filled by weight.  Marks shall be in increments of not more than 20°F.  See Section 215.60 regarding the requirement for thermometer well and thermometer. c)         Gauging devices that require bleeding of the product to the atmosphere, such as the rotary tube, fixed tube, and slip tube devices, shall be designed so that the maximum opening of the bleed valve is not larger than No. 54 (0.055 in.) drill size unless provided with an excess flow valve.  (This requirement does not apply to farm vehicles used for the application of ammonia as covered in Section 215.115.) d)         Gauging devices shall have a design pressure equal to or greater than the design pressure of the container on which they are installed. e)         Fixed maximum liquid level gauges shall be designed and installed to indicate a volumetric level not to exceed 85% of the container’s water capacity. Note: This does not apply to refrigerated storage. f)         Gauge glasses of the columnar type shall be restricted to stationary non-refrigerated storage installations.  They shall be equipped with shutoff valves having metallic hand wheels, excess flow valves, and extra heavy glass adequately protected with a metal housing applied by the gauge manufacturer.  They shall be shielded against the direct rays of the sun.