UL 209-2020 pdf free download.Cellular Metal Floor Raceways and Fittings. 4.2 The connection of a metallic duct, cell or raceway with a fitting shall be tested in accordance with the Grounding and Bonding Test, Section 13. 4.3 A sheet metal screw shall not be used for the connection of an equipment grounding conductor. 5 Protective Coating 5.1 Both the interior and exterior surfaces of a cellular floor unit and all broad surfaces of the accessories mentioned in 6.7 shall be protected against corrosion by a coating of zinc and tested to the requirements in Protective Coating — Zinc, Section 14. The lower element of a floor unit may be protected against corrosion on both the interior and exterior by an enamel coating complying with the requirements in 15.1 — 15.3 if it is: a) Integral with a structural member that protects it from below against physical damage during installation and b) Constructed of sheet steel not less than 0.067 inch (1.7 mm) thick. 5.2 Both the inside and outside surfaces of header duct or trench headers shall be protected against corrosion. If zinc is used, the coating shall comply with the requirements in Protective Coating — Zinc, Section 14. If a metal other than zinc or if a nonmetallic material is used, the corrosion protection afforded by the coating shall not be less than that of the specified zinc coating. If enamel is used, the coating, at any time up to one year from the time of manufacture, shall comply with the requirements in Protective Coating — Enamel, Section 15. 6 Cellular Metal Floor Raceways 6.1 A cellular floor unit shall be made of sheet steel. 6.2 No element shall be thinner than 0.034 inch (0.86 mm) when measured after fabrication but, if the upper element is thinner than 0.056 inch (1.42 mm), the following restrictions apply to the unit: a) If the upper element is thinner than 0.056 inch (1.42 mm), the installation instructions mentioned in 191 shall specify that the upper element is to be protected by at least 1 inch (25 mm) of concrete: b) If the upper element is thinner than 0.045 inch (1.14 mm), it shall be strengthened so that a representative sample of the complete unit complies with the Load Test, Section 10. The cell width and cross-sectional area need not be specified; C) If the upper element is thinner than 0.045 inch (1.14...
Download Address
Download