35. All wires are to be run in standard steel conduit, except those that are so short as to be self-supporting, and these are to be cord wrapped or otherwise protected. No wire smaller than No. 8 to be used.
36. All material and workmanship to be strictly first class. Electrical work must show an insulation resistance of at least 1 megohm, and to be in strict accordance with the latest edition of the “National Electrical Code.”
37. Dust Separator. There shall be one dry separator located where shown on plans, having a volume not less than 3 cu. ft.
38. The interior arrangement of the separator shall be such that no part of same will receive the direct impact of the dust. Cloth bags or metal screens if used in this separator shall be so placed that nothing but the very lightest of the dust can lodge thereon, and that same may be easily cleaned without dismantling the separator. It must be so constructed that it shall intercept not less than 95% of the dust entering same.
38a. Separator tank shall be constructed with steel shells, with either cast iron or steel heads, and be fitted with suitable bases or floor stands for support and proper openings for cleaning same. Separator shall be fitted with iron-column mercury gauge reading 50% in excess of operating vacuum.
39. Pipe Lines. All pipe lines shall be of the sizes and run as indicated on drawings.
40. Pipes. All pipe conveying air is to be standard black wrought-iron or mild-steel screw-jointed pipe, and is to be smooth inside, free from dents, kinks, fins, or burs. Ends of pipe to be reamed to the full inside diameter and beveled. Bent pipe to be used in mains where necessary and where shown on plans.
41. Care must be taken in erecting pipe to maintain as nearly as possible a smooth, uniform bore through all pipe and fittings.
42. Fittings. All fittings to be tough gray cast iron, free from blowholes or other defects; smooth castings in all cases.
43. All fittings on vacuum lines must have inside diameter through body of same size as pipe bore, and all fins, burs, or rough places must be removed.