Section 7104 Of Article 1. Floors And Walls From California Labor Code >> Division 5. >> Part 3. >> Chapter 1. >> Article 1.

. If a span of a floor on a building exceeds 13 feet, an intermediate beam shall be used to support the temporary flooring, but spans not to exceed 16 feet may be covered by three-inch planks without an intermediate beam. The intermediate beam shall be of a sufficient strength to sustain a live load of 50 pounds per square foot of the area supported.