Byline Matt Boulant, PE
West Division Diversified Fall Protection The General Duty Clause of the Occupational Safety and Health Act (Federal OSHA) requires employers to provide a workplace free from recognized hazards that may cause serious injury or death. This clause is often used by OSHA to enforce fall protection requirements. OSHA follows a hierarchy of fall protection controls, which prioritizes certain methods over others. Guardrails are considered one of the preferred methods of fall protection, alongside personal fall arrest systems (PFAS) and safety nets. They are often the first choice for providing passive fall protection.
Guardrails are designed to passively protect workers from falls. Design requirements and loading criteria for guardrails can be found in city adopted building codes. Where code allowed exceptions are met (such as the Occupancy of the building is type S and the occupancy load is less than 50), Federal OSHA regulations and California Division of Occupational Safety and Health (Cal/OSHA) regulations apply.
Federal OSHA regulations for guardrail are found throughout the country. However, Cal/OSHA regulations are only found in California along with Federal OSHA regulations. When guardrails are installed for worker safety in the state of California, Federal OSHA AND Cal/OSHA are the governing regulations that shall be followed. There are some differences in the specific regulations between the two regulations.
Unlike most adopted building code regulations (such as the International Building Code and California Building Code), Cal/OSHA provides additional safety requirements to those set by Federal OSHA rather than a full replacement. When designing guardrails in California, both Federal OSHA and Cal/OSHA shall be adhered to.
Federal OSHA regulations state that guardrails must be installed along any open-sided walking surface or platform that is 4 feet or more above a lower level. The top rail of the guardrail must be 42 inches (+/- 3 inches) above the walking surface, and the mid-rail must be installed halfway between the top rail and the walking surface. The guardrails must be able to withstand a force of at least 200 pounds applied in a downward or outward direction. When the 200-pound point load is applied, the top rail shall not deflect to a height of less than 39”.
Cal/OSHA regulations are similar, but there are some differences. Most importantly, Cal/OSHA states that guardrails shall be provided on all open sides of unenclosed elevated work locations where the elevation difference to the level below is more than 30 inches different. Cal/OSHA also requires that the top rail of the guardrail must be installed between 42 and 45 inches above the walking surface with a permissible height tolerance of 1 inch. Additionally, Cal/OSHA requires that the guardrails must be able to withstand a live load force of at least 20 pounds per linear foot applied in a downward or outward direction along the top rail in addition to Federal OSHA requirements.
The spacing of vertical posts differs between the two sets of code as well. When designing a guardrail system outside of California, the vertical post spacing is typically governed by the horizontal span of the top rail by applying a 200 lbs point load at the center. Federal OSHA does not specify a maximum post spacing but allows for calculations to optimize the layout. Cal/OSHA limits post spacings to 8 feet on center even if the posts and rails are capable of longer spans.
Toeboards are installed at the base of guardrails to protect from objects falling from between the guardrail posts. Both Federal OSHA and Cal/OSHA require toeboards to be a minimum of 3.5 inches tall as measured from the top edge of the toeboard to the level of the walking surface with no more than a ¼ inch gap between the bottom of the toeboard and the walking surface. Federal OSHA does provide an exception around vehicle repair, service, or assembly pits for the toeboard height to be reduced to 2.5 inches.
It's also worth noting that Cal/OSHA has additional requirements for guardrails in specific industries or situations, such as construction and scaffolding. Therefore, it's important for employers in California to be familiar with the Cal/OSHA regulations specific to their industry and work environment to ensure compliance and worker safety.