Guardrails are made up of three major components: a top rail, a mid rail, and a toe board. The top rail is the vertical component that runs along the edge of the roadway. It provides protection for drivers who may lose control of their vehicles. The mid rail is the horizontal component that extends out from the top rail at a 45-degree angle. It provides additional protection for vehicles that have skidded off the road but not into the ditch. The toe board is the horizontal component that extends out from the mid rail at a 90-degree angle. It protects drivers who need to move their cars or trucks in order to exit the highway.
The type of guardrail used on a given project will depend on several factors, such as the grade of the roadbed, the safety characteristics desired by the highway department, and the cost effectiveness of various types of guardrails. Guardrail systems can be divided into three general categories: continuous, discontinuous, and hybrid.
Continuous guardrails consist of a single metal pole set back from the edge of the road about two feet with the upper section bent down over the edge of the roadbed. The bottom end of the pole is buried in the ground with only its tip showing above soil level.
A guardrail is a barrier intended to prevent a fall from an elevated area, such as a deck or balcony. When a guardrail runs the length of a stairwell (or a ramp with a rise larger than 6 inches), building rules will also require a secondary handrail. Guards and handrails are required by law on all exterior staircases in new construction and major renovations. Existing buildings must comply with current codes when they are renovated or rebuilt.
The purpose of a guardrail is to prevent people from falling off of their property. Handrails are used to provide additional support where guards won't go; they also serve as a safety device for people who might be using the stairs with objects in their hands. The National Safety Council recommends that any handrail on stairs be at least 1-1/4 inches thick. Thinner rails are more flexible and may not give enough support to be effective guardrails.
People who are afraid of heights should not use stairs as a means of access into buildings because it is impossible to stop once you've started down. Guardrails can only do so much to protect those who use them. If you use stairs, even if they're enclosed within a railing, you should still be afraid to walk up them.
In the construction industry, guardrails are the principal form of fall safety. It is a type of passive fall prevention that functions as a physical barrier to keep individuals from falling to lower levels. A guardrail is made by : The top rail is 42 inches (plus or minus 3) above the walking/working level. The bottom rail is 7 1/4 inches (plus or minus 3) below the ground line. Both rails must be free-standing and straight. They cannot be attached to any other structure.
The purpose of guardrails is to prevent people from falling off of structures such as roofs or balconies. Guardrails can also protect people from running into open areas where they might be hit by moving vehicles or injured by thrown objects. There are three main types of guardrails: metal guardrails, wooden guardrails, and plastic guardrails.
Metal guardrails are the most common variety and are usually made of steel with aluminum or vinyl coatings for weather resistance. These guardrails are designed to look attractive while still providing effective protection. They can be flat or curved, depending on what type of roof they are used on. Metal guardrails are available in a wide range of colors and styles; therefore, they can match any home exterior decor. They can be bent to fit around objects such as trees or posts for a custom look.
Guardrail systems must bear a force of at least 200 pounds (890 N) applied within 2 inches (5.1 cm) of the top edge in either outward or downward direction, at any position along the top edge, without failure. This means that the maximum load that can be supported by the guardrail system is 200 pounds (890 N). The minimum height required for adequate protection is based on this maximum load.
The minimum force that must be applied to the guardrail for it to protect adequately is also called its "breakaway force." The breakaway force of a guardrail is the combined weight of a vehicle traveling at 55 miles per hour (88 km/hr), a pedestrian weighing 150 pounds (68 kg), and a shield barrier designed to prevent head-on collisions with vehicles attached to a vehicle traveling in the opposite direction. This equals about 300 pounds (136 kg).
The guardrail must be capable of supporting this breakaway force within 2 inches (5.1 cm) of the top edge of the rail for it to provide sufficient protection.
The breakaway force increases as road hazards such as hills and curves are encountered by the moving vehicle. For example, if the same vehicle continues on its path down the hill, then the breakaway force would decrease to 100 pounds (45 kg).