R307-355-8. Solvent Cleaning

  (1) Hand-wipe cleaning. Cleaning solvents (excluding water and exempt solvents) used in hand-wipe cleaning operations on aerospace vehicles or components shall meet one of the following requirements:

  (a) Have a VOC composite vapor pressure less than or equal to 45 mm Hg at 68 degrees Fahrenheit;

  (b) Have an aqueous cleaning solvent in which water is at least 80% of the solvent as applied; or

  (c) Have a low vapor pressure hydrocarbon-based cleaning solvent.

  (2) The following exemptions apply:

  (a) Cleaning during the manufacture, assembly, installation, maintenance, or testing of components of breathing oxygen systems that are exposed to the breathing oxygen.

  (b) Cleaning during the manufacture, assembly, installation, maintenance, or testing of parts, subassemblies, or assemblies that are exposed to strong oxidizers or reducers (e.g., nitrogen tetroxide, liquid oxygen, hydrazine).

  (c) Cleaning and surface activation prior to adhesive bonding.

  (d) Cleaning of electronics parts and assemblies containing electronics parts.

  (e) Cleaning of aircraft and ground support equipment fluid systems that are exposed to the fluid, including air-to-air heat exchangers and hydraulic fluid systems.

  (f) Cleaning of fuel cells, fuel tanks, and confined spaces.

  (g) Surface cleaning of solar cells, coated optics, and thermal control surfaces.

  (h) Cleaning during fabrication, assembly, installation, and maintenance of upholstery, curtains, carpet, and other textile materials used on the interior of the aircraft.

  (i) Cleaning of metallic and nonmetallic materials used in honeycomb cores during the manufacture or maintenance of these cores, and cleaning of the completed cores used in the manufacture of aerospace vehicles or components.

  (j) Cleaning of aircraft transparencies, polycarbonate, or glass substrates.

  (k) Cleaning and solvent usage associated with research and development, quality control, or laboratory testing.

  (l) Cleaning operations, using nonflammable liquids, conducted within five feet of energized electrical systems.

  (3) Flush cleaning. Cleaning solvents used in flush cleaning of aerospace vehicle or component parts, assemblies and coating unit components must be emptied into an enclosed container or collection system that is kept closed when not in use.

  (4) Spray gun cleaning. All spray guns used to apply coatings to aerospace vehicle or component shall be cleaned by one or more of the following methods:

  (a) Enclosed system that is closed at all times except when inserting or removing the spray gun. If leaks in the system are found, repairs shall be made as soon as practicable, but no later than 15 days after the leak was found. If the leak is not repaired by the 15th day, the cleaning solvent shall be removed and the enclosed cleaner shall be shut down until the leak is repaired or its use is permanently discontinued.

  (b) Nonatomized cleaning.

  (i) Spray guns shall be cleaned by placing cleaning solvent in the pressure pot and forcing it through the gun with the atomizing cap in place.

  (ii) The cleaning solvent from the spray gun shall be directed into a vat, drum, or other waste container that is closed when not in use.

  (c) Disassembled spray gun cleaning.

  (i) Spray guns shall be cleaned by disassembling and cleaning the components by hand in a vat, which shall remain closed at all times except when in use.

  (ii) Spray gun components shall be soaked in a vat, which shall remain closed during the soaking period and when not inserting or removing components.

  (d) Atomizing spray into a waste container that is fitted with a device designed to capture atomized solvent emissions.

  (e) Cleaning of the nozzle tips of automated spray equipment systems, except for robotic systems that can be programmed to spray into a closed container, shall be exempt from these requirements.