Archive Notice - OSHA Archive

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September 22, 1980

Mr. Wayne F. Alch, P.E.
Vice President/Manager
Brooks Erection & Construction Co.
9624 Mammoth
Baton Rouge, La. 70814

Dear Mr. Alch:

This is in reference to your request for a variance from Section 1926.451(a)(4), (5), and (10) Scaffolding, of the Safety and Health Regulations for Construction.

Our technical staff is reevaluation those situations involving the use of toeboards as required by Section 1926.451(a)(4). A number of variances have been granted to members of the Steel Plate Fabricators Association and others to eliminate toeboards from scaffolds during the construction of steel tanks and silos on those types of jobs which were isolated and involved a minimum number of employees. The variances were granted on the basis that employees were not exposed to the hazard or material falling from the scaffold. These variances were not intended to apply on large construction jobs where multiple tradesmen are involved in various tasks which could cause them to be subjected to an overhead hazard.

Therefore, on those tank erection jobs which are isolated situations involving a minimum number of employees from a particular trade (such as the boilermakers) where employees are not subjected to an overhead hazard toeboards would not be required. In these cases, the usual precautions shall be taken such as loose tools and equipment shall be kept in well-designed tool containers and the areas beneath and far enough away from the scaffold to be struck by anything that might fall from above shall be barricaded and posted with clearly visible signs stating "NO TRESPASSING DANGER OVERHEAD WORK".

Section 1926.451(a)(5) states that guard rail support shall be at intervals not to exceed eight (8) feet. On specialty type scaffolding which is system designed to accommodate a particular type of construction guard rail support (metal) may exceed the 8 foot intervals. However, these guardrails shall be at least of equivalent strength, stability and height as those required for the 8 foot intervals of 2" x 4" wood rails required by Section 1926.451(a)(5).

Finally, Section 1926.451(a)(10) requires that all planking shall be Scaffold Grade or equivalent and the maximum permissible span 2" x 10" or wider planks shall be no greater than 10 feet. In those instances, when specialty system designed scaffolding is used, such as in steel plate tank erection, the plank span may be extended to 10' 6" provided that the planks are rough full dimensioned 2" x 12" x 12' planks of Dense Select Structural Grade or equivalent. Three (3) planks with full thickness 2" x 10" x 12' dimensions may be used in lieu of two (2) 2" x 12" x 12' planks provided that they are clamped or bonded together at the midpoint of the span, in order to spread the weight of the employees.

Affected employees and their authorized representatives shall be notified of this clarification in the same manner they were informed of your request for a variance.

Accordingly, no further action will be taken on your request for a variance.


James J. Concannon
Office of Variance Determination