9 CFR § 590.542 - Spray process drying operations.
(a) The drying room shall be kept in a clean condition and free of flies, insects, and rodents.
(b) Low-pressure lines, high-pressure lines, high- and low-pressure pumps, homogenizers, and pasteurizers shall be cleaned by acceptable inplace cleaning methods or dismantled and cleaned after use or as necessary when operations have been interrupted.
(1) Spray nozzles, orifices, cores, or whizzers shall be cleaned immediately after cessation of drying operations.
(2) Equipment shall be sanitized within 2 hours prior to resuming operations.
(c) Drying units, conveyors, sifters, and packaging systems shall be cleaned whenever wet powder is encountered or when other conditions occur which would adversely affect the product. The complete drying unit, including sifters, conveyors, and powder coolers shall be either wet washed or dry cleaned. A combination of wet washing and dry cleaning of the complete drying unit shall not be permitted unless that segment of the unit to be cleaned in a different manner is completely detached or disconnected from the balance of the drying unit.
(1) Sifters and conveyors used for other than dried albumen shall be cleared of powder when such equipment is not to be used for a period of 24 hours or longer.
(d) Powder shall be sifted and the screen shall be replaced whenever torn or worn.
(e) Accumulations of large particles or lumps of dried eggs shall be removed from the sifter screens continuously.
(f) All openings into the drier around ports, augers, high-pressure lines, etc., shall be closed to the extent possible during the drying operation to prevent entrance of nonfiltered air.
(g) Openings into the drying unit shall be closed when the drier is not in use, except when the drying unit has been completely emptied of powder and wet washed. This includes, but is not limited to, openings, for the air intake and exhaust systems, nozzle openings, ports, augers, etc.