The title of this article is like a phrase, “Guardrail systems must be able to withstand”?
You can paraphrase the question thus –
- What should be the minimum capacity of your guardrail?
- What should be the minimum strength of your guardrail, or
- What should be the minimum requirements of your guardrail.
At the end of this article, you will have an answer to this question; any how its being framed or presented. The answer to this question is presented in the OSHA guardrail requirements.
Before we get to the main subject, let us have a brief discussion on the guardrail systems.
Guardrails systems is a system composition of stationary (or “fixed”) materials used to protect workers from falls when working at heights. They are a preferred means of protecting workers because the system does not rely on the worker to be trained to use, inspect, and wear a fall protection system.
Guardrails are typically composed of strong metals which are concreted into the ground or bolted down so that they cannot be moved by human force. They can also be considered as obstacles, and so the risk of placing them must be weighed against their protective properties. A guardrail will not stop the total impact should a vehicle crash into it, however, it does stop pedestrians being forced by crowds into the roads, and prohibits them from walking into the road where it is unsafe, or there is a steep drop.
There are some types of guard rails:
Types Of Guard Rails
The most common types of guardrails include:
W-beams are the standard traffic and highway safety rails and are constructed in high gauge steel. To protect against environmental conditions, this type of beam is fabricated with zinc coatings and weather (resistant) coated materials.
Curved guardrails feature a convex or concave-shaped rail and are used to provide protection on roadways and highways that have a bend radius to them. These units are usually prefabricated to fit the required dimensions of the site where they will be installed. Concave rails are those in which the rail curves in towards the vehicle, while convex rails are those that curve away from the vehicle.
Drop-in rails feature brackets that allow post sections to slide into the structure upon installation. This type of railing is easily accessible.
Bolt-on rails involve specific installation with hand tools and drills, though the hardware for this type of railing is typically included by the manufacturer. Single, double, or triple rails may be selected for an application.
Where Should Guard Rails Be Place:
Guardrails should typically be positioned in areas where there is risk of fall from height, the divide between pedestrians and traffic is small, or there are tight corners where vehicles are in close proximity to pedestrian areas at the edge of walkways. Wherever there is a high collision risk if pedestrians cross into the road, guardrails should be placed for the protection of pedestrians to reduce injuries if they were to walk out into the road.
OSHA Guardrail Requirements
Where workers on a construction site are exposed to vertical drops of 6 feet or more, OSHA requires that employers provide fall protection in one of three ways before work begins:
- Placing guardrails around the hazard area.
- Deploying safety nets.
- Providing personal fall arrest systems for each employee.
Many times the nature and location of the work will dictate the form that fall protection takes. If the employer chooses to use a guardrail system, he must comply with the following provisions:
- Top edge height of top rails, or equivalent guardrail system members, must be between 39 and 45 inches above the walking/working level, except when conditions warrant otherwise and all other criteria are met (e.g., when employees are using stilts, the top edge height of the top rail must be increased by an amount equal the height of the stilts).
- Midrails, screens, mesh, intermediate vertical members, or equivalent intermediate structures, must be installed between the top edge and the walking/working surface when there is no wall or other structure at least 21 inches high.
- Midrails must be midway between the top edge of the guardrail system and the walking/working level.
- Screens and mesh must extend from the top rail to the walking/working level, and along the entire opening between rail supports.
- Intermediate members (such as balasters) between posts must be no more than 19 inches apart.
- Other structural members (such as additional midrails or architectural panels) must be installed so as to leave no openings wider than 19 inches.
- Guardrail systems must be capable of withstanding at least 200 pounds of force applied within 2 inches of the top edge, in any direction and at any point along the edge, and without causing the top edge of the guardrail to deflect downward to a height less than 39 inches above the walking/working level.
- Midrails, screens, mesh, and other intermediate members must be capable of withstanding at least 150 pounds of force applied in any direction at any point along the midrail or other member.
- Guardrail systems must not have rough or jagged surfaces that would cause punctures, lacerations, or snagged clothing.
- Top rails and midrails must not cause a projection hazard by overhanging the terminal posts.
Now for the question we need to answer in this article – “Guardrail systems must be able to withstand”?
Guardrail Systems Must Be Able To Withstand?
According to OSHA – Guardrail systems must be capable of withstanding at least 200 pounds of force applied within 2 inches of the top edge, in any direction and at any point along the edge, and without causing the top edge of the guardrail to deflect downward to a height less than 39 inches above the walking/working level.
I believe the question has been answered with a little overview on the guardrail system. For questions and contributions, please use the comment box.