Under the guidelines of the Occupational Safety and Health Administration, the contractor is responsible for the safety of scaffolding--even if it's rented, even if the equipment is defective or mislabeled. OSHA has very specific requirements for the performance of scaffold planking.
  • it must be able to support its own weight and at least four times the intended load.
  • when fully loaded, the plank cannot deflect more than 1/60 of the span

Solid-sawn wooden planks used as scaffold planking must be inspected and graded by a certified inspector. Manufactured planks are also acceptable and are to be used as recommended by the manufacturer. If you use what OSHA recommends, you will pass your safety inspection (assuming the boards are in good condition). If you use any other lumber for planking, you may have to demonstrate that they meet the performance requirements. A much more important reason to follow the OSHA suggestions on scaffold planking is your workers' safety. Fortunately, there are alternatives to solid-sawn wooden planks: manufactured (or engineered) lumber planks, steel or aluminum planks, and platforms. This article focuses on engineered lumber planks. Manufactured wood scaffold planks come in three configurations:

  • Laminated veneer lumber
  • Glued laminated lumber (glulam)
  • Pinned planks

Engineered lumber plank has gained in popularity over the past few years because of several advantages over solid-sawn:

  • Longevity
  • Stiffness and strength
  • Certification
  • Cost

The scaffold system is only as safe as its components. Plank selection, maintenance, and storage are critical. Regular inspection of the planks by your competent person is an OSHA requirement. Overall, about 70% of scaffolding is rented. The manufacturers are the best sources of information on engineered planks. The article also includes information on laminated veneer lumber and a chart comparing properties of various manufacturers' scaffold planks.