competent attendant shall supervise the transfer of liquids from the time the
connections are first made until they are disconnected.
(2) Pumps shall be of a material suitable for use with the solution being
handled and designed to withstand the working pressure.
(3) Air compressors may be used for transfer of nitrogen fertilizer
(a) The air compressor shall be protected with a back flow check valve in
the air line to prevent the flow of nitrogen fertilizer solutions or vapor from
the container into the air compressor.
(b) A relief valve large enough to discharge the full capacity of the
compressor shall be connected to the discharge before any shutoff valve.
(4) All storage installations shall be equipped with devices so as to
minimize tampering while installation is unattended.
(5) Containers shall be filled or used only upon authorization of owner or