Guard rail

Park and garden railings commonly in metalworking feature swirls, leaves, plate metal areas and/or motifs particularly on and beside gates.

Handrails along stairways may be supported by balusters forming a balustrade, and catwalks (a type of footbridge) and balconies are also lined with them.

In the US this is typically built on-site from pressure treated lumber thus featuring a simplistic design of vertical baluster spaced every 3.5 inches (8.9 cm) demonstrating compliance with building codes (standards).

There are three exceptions according to the 2003 International Building Code Section 1012.3 which allow openings to not exceed 8 or 21 inches (20 or 53 cm) depending on occupancy groups or special areas.

As governments around the world courted the voting power of working people and trade unions in the 1980s, the health and safety rights of workers became of greater importance.

This set the governmental procedures in motion that would see a flurry of regulations and legislation around workplace safety being introduced in industrialized countries in the 1990s.

In the US, under OSHA Standard 1910.28(b)(15), employees who work on surfaces that are 4 feet (1.2 m) or higher off of the ground must have personal fall protection systems in place, such as handrails or guardrails.

The facility safety guardrails control in-plant vehicular traffic and protect areas where errant vehicle contact may cause harm to property or personnel.

The guardrail provides a safety barrier preventing lift trucks or other in-plant vehicles from traveling into equipment, building walls, or personnel.

In industrial and distribution facilities the steel guardrail systems provide solid protection for property and personnel by restricting and controlling where in-plant vehicular traffic may operate.

While a single rail safety guardrail located some 15 inches (38 cm) above floor level may be sufficient to control vehicle traffic, it could present a trip hazard to pedestrians since it is not as noticeable as a double or triple guardrail system where the top rail is some 40 inches (100 cm) above the floor level.

Each grade is suited to a different application which may be determined by size and type of vehicles used in the facility, the volume of traffic to be controlled, or the value/risk associated with the areas being guarded.

At the turn of the 21st century, several companies developed safety products constructed with polymer designed specifically for industrial environments and in 2001 a dedicated industrial alternative to steel guardrail was invented by A-SAFE, a British-based company, and thus the first fixed flexible polymer safety guardrail was introduced to the market.

In traffic engineering, a highway guardrail may prevent an errant vehicle from hitting roadside obstacles, which may be either man-made (sign structures, culvert inlets, utility poles) or natural (trees, rock croppings), running off the road and going down a steep embankment, or veering off the roadway into oncoming traffic (commonly referred to as a median barrier).

For instance the optimum height of the strong-post W-beam for a car might not keep a truck from toppling over it, while a motorbike might slip under a higher rail.

As a result, the Midwest Guardrail System (MGS) was developed and successfully crash tested per NCHRP Report 350 TL-3 criteria.

One other significant difference is that MGS rail splices occur at mid-span compared to at the posts like the strong-post W-beam guardrail.

A guardrail is effectively one strong band that transfers the force of the vehicle to the rail elements, posts, and end terminals or anchors.

Newer concrete barriers, while usually strong enough to withstand direct hits by cars, still work on a similar principle in deflecting heavier vehicles such as trucks.

Modern installations of guardrails are designed to allow the guiderail to deform under the load of the crash, and safely redirecting a vehicle back onto the roadway at a somewhat shallow angle.

Guardrailing must be installed so that it is not so rigid that the rail will fail upon impact or the posts will snap off at the point where they are embedded within the ground.

In addition to new research into end treatments, public awareness among both drivers and engineers has been gradually reducing injuries and fatalities due to guardrails.

While cheaper guardrail is the weakest, often being destroyed from the impact of a light vehicle, it is inexpensive and quick to repair, so this is frequently used in low-traffic rural areas.

On the other hand, concrete barriers can usually withstand direct hits from a larger variety of vehicle types, making them well suited for use on high volume routes such as freeways or ramps with sharp curves.

[27] This was after London's Royal Borough of Kensington and Chelsea did so and found that the rate of injury to pedestrians decreased three times faster than elsewhere in the city.

[27] The removal of barriers divorcing wheeled traffic from pedestrians is an essential of the shared space paradigm and philosophy in urban design.