ASTM ( American Society for Testing and Materials)

ASTM A568 — Standard specification for steel, carbon and high-strength; low alloy hot-rolled sheet; hot-rolled strip; corl-rolled sheet.

ASTM A525 — Standard specification for steel sheet, zinc-coated (galvanized) by the hot-dip process.

ASTM A386 — Standard specification for zinc-coatings (ho-dip) on assembled steel products.

ASTM A153 — Standard specification for zinc coatings (hot-dip) on iron and steel hardware.

NEC (National Electrical Code)

NEC Article 318 — Cable Trays.

NEMA (National Electrical Manufacturers Assosciation)

NEMA — VE1 (current issue)
PERFORMANCE STANDARDS and CLASS DESIGNATIONS

VE 1-3.01 WORKING (ALLOWABLE) LOAD CAPACITY
The working (allowable) load capacity represents the ability of a cable tray to support the static weight of cables. It is equivalent to the destruction load capacity, as determined by testing in accordance with par. VE 1-4.01, divided by a safety factor of 1.5
NEMA Standard 3-14-1979

VE 1-3.02 LOAD/SPAN CLASS DESIGNATIONS
There shall be three working load catagories of cable tray:*

1. 50 lb./lin. ft. (Symbol A)
2. 75 lb./lin. ft. (Symbol B)
3. 100 lb./lin. ft. (Symbol C)

and, four support span catagories of:

1. 8 ft.
2. 12 ft.
3. 16 ft.
4. 20 ft.

Utilizing thses, the load/span designations of Table 3-1 shall apply.

* For deflection, see par. VE 1-601, NEMA Standard 3-14-179