15.2.1.3 A thorough inspection of the operating area shall take place on an as-needed basis to help ensure that the equipment is in good condition and that proper work practices are being fol- lowed.
15.2.1.3.1 The inspection shall be conducted at least quarterly.
15.2.1.3.2 The inspection shall be conducted by a person(s) knowledgeable in the proper practices who shall record the find- ings and recommendations.
15.2.1.4 Operating and maintenance procedures shall be re- viewed annually and as required by process changes.
15.2.2 * Housekeeping.
15.2.2.1 A documented housekeeping program shall be es- tablished.
15.2.2.2 Fugitive metal dust shall not be allowed to accumulate to a level that creates a potential secondary explosion or flash-fire hazard.
15.2.2.3 Systematic cleaning of areas containing dust- producing equipment, including roof members, pipes, con- duits, and other components shall be conducted as fre- quently as conditions warrant.
15.2.2.3.1 The cleaning shall include machinery.
15.2.2.3.2 Cleaning methods shall be limited to those methods that minimize the probability of fire or explosion, as determined by a person knowledgeable in the properties of combustible- metal dusts.
15.2.2.3.3 Chips or powder sweepings shall be removed to a designated storage or disposal area.
15.2.2.3.4 Special attention shall be paid to areas utilizing powder for accumulations in crevices and joints between walls, ceilings, and floors.
15.2.2.4 Bulk Accumulations.
15.2.2.4.1 Spills shall be removed at once, using conductive scoops and soft bristle brushes that have natural fiber bristles.
Scoops shall be nonsparking unless otherwise authorized for the specific application.
15.2.2.4.2 Vacuum Cleaning.
15.2.2.4.2.1 Vacuum cleaning systems shall be used only for removal of dust accumulations too small, too dispersed, or too inaccessible to be thoroughly removed by hand brushing.
15.2.2.4.2.2 Vacuum cleaning systems shall be effectively bonded and grounded to minimize the accumulation of static electric charge.
15.2.2.4.2.3 * Because of the inherent hazards associated with the use of vacuum cleaning systems and portable vacuum systems for finely divided combustible metal dusts, special engineering analysis shall be given to the design, installation, maintenance, and use of such systems.
15.2.2.4.2.4 Portable vacuum cleaners shall be used only if rated or approved for use with combustible metals dust.
(A) They shall be permitted only for small amounts of re- sidual material remaining after preliminary cleanup.
(B) They shall be emptied at the end of each operational period or shift.
(C) They shall not be used as primary dust collectors.
15.2.2.4.2.5 Vacuum cleaner hose, nozzles, and fittings shall be made of conductive nonsparking material.
15.2.2.4.2.6 Assembled components shall be conductive and bonded where necessary.
15.2.2.4.2.7 Periodic test for continuity shall be performed.
15.2.2.4.2.8 Combustible metal dust picked up by a fixed vacuum cleaning system shall be discharged into a container or collector location outside the building.
15.2.2.4.3 Compressed-Air Cleaning Requirements. 15.2.2.4.3.1 Compressed-air blowdown shall not be permit-
ted, unless the conditions of 15.2.2.4.3.2 are met.
15.2.2.4.3.2 In certain areas that are otherwise impossible to clean, compressed-air blowdown shall be permitted under con- trolled conditions with all potential ignition sources prohibited in or near the area and with all equipment shut down