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That Hurts!

By David H. Glabe, P.E. / December 31, 2002

In the good old days, that is, prior to the present Occupational Safety and Health Administration, OSHA, scaffold standards, fall protection included toeboards. Old habits die hard and some people think that toeboards are still part of a fall protection system. Now, unless you are literally laying down on the job, a toeboard won’t do much to keep you from falling off a scaffold platform. In fact, the present scaffold standards clearly separate the fall protection requirements from the falling object protection requirements, which clearly what a toeboard is. What does this all have to do with fall protection? Nothing, except that both fall protection, and falling object protection help keep people from getting injured or killed.

 

While the theme this month is fall protection, falling object protection is rarely properly addressed and now is a good time to clarify protection against falling objects. First, a common misconception is that toeboards are always required on any scaffold platform. This is not true. What is true is workers, and others, must be protected from falling objects. A toeboard may work. Other things work too. My personal favorite is a barricade around the scaffold. That way nobody can get under the scaffold to get hit by falling objects. Unfortunately, a barricade won’t work for employees working directly below others. In this case a toeboard, canopy or other method of protection will be required.

 

If you choose to use a toeboard, it must meet certain minimum requirements. It must be at least 3-1/2 inches tall, taller if the objects on the platform can fall over the toeboard. This would suggest that a five gallon bucket may need a taller toeboard, screening, or paneling. If screening or paneling is used, it shall extend to the top of the toprail. Remember, there is no such thing as a toeboard being too tall. A 2×10 scaffold plank on edge works nicely as a toeboard. The toeboard must be strong enough to resist a 50 pound force. 2×4 lumber may not work at longer spans, so before assuming a 2×4 will solve all your problems, have your qualified person qualify your toeboard. The maximum gap between the bottom of the toeboard and the platform can be no more than ¼ inch. No big deal until the plank deflects under your weight. You may want to solve this dilemma by firmly attaching the toeboard to the plank or use fabricated planks that won’t deflect under load.

 

Frequently, canopies are used for falling object protection, particularly where people are to pass under the scaffold. However, be careful using a canopy to stop objects from hitting somebody; it may not work. The physics affecting falling objects is no different than the physics affecting falling employees. That means that falling objects pick up speed, and force, as they fall. For example, a 200 pound falling concrete block will generate a force of almost 2,400 pounds in just a drop from one scaffold platform 6’-6” down to another platform. That’s a lot of force! No scaffold plank will hold that load. That means a canopy constructed, for example, of scaffold plank and plywood, may be worthless, depending on what workers above are dropping. Keep in mind that constructing a pedestrian canopy from plank and plywood could have the same design inefficiencies.

 

On occasion, catch platforms and debris nets are used to stop falling objects. Because of the forces involved, they can become complicated to design and install. Therefore they must be, as with all components of a scaffold, be designed by a qualified person. Always install the catch platform as close as possible to the falling object so high forces are not developed.

 

The bottom line on falling object protection is to do whatever it takes to protect those below. Choices are available and only need to be employed where the hazard exists. A combination of methods can be employed, as determined by the qualified scaffold designer. The choice of method will depend on the type of scaffold, the work activity and the potential falling object. For example, a toeboard is a good choice for a mobile scaffold since the scaffold can be at various locations, adjacent to other workers, and objects on the platform may roll off during a move. As we say, look at the intent of the standard, and respond accordingly. If someone can get hit by objects falling off the scaffold platform, provide protection.

Tags: Fall Protection OSHA Standards & Regulations Resources toeboards

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