Questions You Have Asked About OSHA

By David H. Glabe, P.E. / July 31, 2000

What is a scaffold?

A scaffold is “any temporary elevated platform (supported or suspended) and its supporting structure (including points of anchorage), used for supporting employees or materials or both.” (OSHA 29CFR 1926.250) This includes frame scaffolds for example, and also two planks supported by two barrels or concrete blocks.


What is a limited access zone?

A limited access zone is established whenever a masonry wall is being constructed. It is an area that is established on the side of the wall which will be unscaffolded and its purpose is to eliminate the hazard of the wall, while being constructed, and before it is braced, from falling on employees. For more information, see Subpart Q of the OSHA Construction Industry Standards, 29 CFR 1926.


What is a qualified person, as it pertains to scaffolding?

A qualified person is one of two types of individuals. The first individual has a degree, certificate, or professional standing. The second individual has extensive knowledge, training, and experience. In either case, the individual must be able to demonstrate an ability to solve or resolve scaffold related problems.


What is a competent person, as it relates to scaffolding?

In the words of OSHA: “A competent person must have had specific training in and be knowledgeable about the structural integrity of scaffolds and the degree of maintenance needed to maintain them. The competent person must also be able to evaluate the effects of occurrences such as a dropped load, or a truck backing into a support leg that could damage a scaffold. In addition, the competent person must be knowledgeable about the requirements of this standard. A competent person must have training or knowledge in these areas in order to identify and correct hazards encountered in scaffold work.”


What are the five most serious scaffold hazards?

Based on accident statistics, the five hazards are: 1) Falls; 2) Unsafe Access; 3) Struck by Falling Objects; 4) Electrocution; 5) Scaffold Collapse.


Is it necessary to train scaffold erectors?

Yes; it is required by law.


Is it necessary to train scaffold users?

Yes; it is required by law.


Does Federal OSHA require all scaffolds to be designed by a qualified person?



What is ANSI?

ANSI is the American National Standards Institute. It is an organization whose members include individuals from academia, industry, and government who develop industry consensus standards for products and processes. The scaffold standard is A10.8-1988. The aerial platform standards are in the A92 series. Several SIA members are also members of ANSI committees and subcommittees and the SIA is the secretariat for the Aerial Platform Standards.


What is a safety factor in scaffolding?

A safety factor is an adjustment to the load rating of a scaffold component. In the case of scaffolding, the minimum safety factor is 4. For certain components, such as the suspension ropes for suspended scaffolds, the minimum safety factor is 6. For shoring equipment, the safety factor ranges from 2 to 3. Generally, the safety factor is applied to account for unknown factors.


Has training always been required by OSHA?

Yes. Training requirements can be found in Subpart C, General Safety & Health Provisions of the Construction Industry Standards. When the scaffolding standards were updated, specific training requirements for scaffold users, erectors, inspectors, maintainers, and others, were included. These specific training requirements do not replace the original training requirements but rather enhance and clarify the training requirements for the scaffold industry.


Does OSHA have a web site?

Yes. It is www.osha.gov.


How much does the wind affect erected supported scaffolds?

The effect of the wind on scaffolds is varied based on many factors, including the height of the scaffold, the location of the scaffold, the surrounding environment, the shape of the structure, and whether the scaffold is enclosed, to mention a few. The OSHA minimum tie-in requirements are exactly that: a minimum requirement. Doubling up ties when a scaffold is enclosed seldom is adequate. The only reason more scaffolds don’t fall over is because the wind hasn’t blown very hard and/or the safety factor is compromised.


If a supported scaffold is enclosed, and the ties are installed according to the OSHA minimum requirements, what is the potential force on each tie?

Depending on conditions and location, it can be near zero, (no wind,) to 9,000 pounds.


Is continuous cross bracing required on all frame scaffolds?

No. While it is a good idea to install continuous bracing, and manufacturers recommend it, continuous bracing is not required provided proper bracing is installed. If you don’t know what proper bracing is, install continuous bracing.



Who determines what is proper bracing?

The qualified person determines what proper bracing is. Typically, the bracing requirements are shown on the design. In some cases, general guidelines, such as those developed by manufacturers, can be developed for a given scaffold.


If a cross brace is missing from one bay of a continuous bay scaffold, is this in violation of the OSHA standards?

Not necessarily. The standards require that all supported scaffolds be braced to “prevent swaying and displacement.” This can be accomplished by a combination of cross, diagonal and straight braces, in combination with sufficient tie-ins.


Are clamp-on ladders considered “fixed” ladders and consequently must comply with Federal OSHA Subpart X standards?

No. Clamp-on ladders are a scaffold component and consequently are addressed in the scaffold standards, Subpart L. Clamp-on ladders are not fixed ladders.


Does OSHA have any guidelines for the compliance officers pertaining to the enforcement of the scaffold standards?

Yes; it’s OSHA Instruction CPL 2-1.23 (Directive) and can be found on the OSHA website.

Tags: Scaffolding ANSI limited access zone OSHA Standards & Regulations qualified scaffold person Resources Safety Hazards scaffold training factors

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