In a prior post about ANSI/ASSE 810.8-2011: Scaffolding Safety Requirements, we discussed a standard that is intended to protect both construction workers and pedestrians passing by structures as they are being built or remodeled. The main danger posed from this is that the buildings, while once complete, are being partially destroyed so that they can be enhanced in the future. This occurs with many kinds of construction and remodeling, and it exposes individuals to threats that they would regularly be buffered from. This is not unique to building construction.
Roadwork, much like maintenance on buildings, requires destruction of the material being worked, which can be either partially destroyed or in perfect condition prior to rebuilding. The intention with this deconstruction is to provide something that can enhance the future performance of the road, or to improve on something that is obstructed by the road but has no direct relation with it. For example, a recent storm could have damaged the pavement of the road and it needs to be filled in to reduce damage to car tires. There could also be gas pipes that can only be accessed through the road, which would require a perfectly fine road to be damaged and rebuilt. No matter how it is done, there will need to be a work zone. Traffic control work zones are covered in the Australian standard AS 1742.3-2009: Manual of uniform traffic control devices – Traffic control for work on roads.
Roadwork can lead to heavy traffic, especially on major roads. Roads are traditionally designed to achieve the most efficient traffic flow. This explains the traditional placement of stoplights and signs. Traffic delays can cause economic impact if this system is disturbed. Management of work zones can help to maintain some semblance of the proper movement of traffic. AS 1742.3-2009 establishes a set of guidelines that provide safety for drivers and construction workers, while taking into consideration the proper labeling of bike paths and walkways.
One of the primary differences between work on a building and work on a road is that the road often cannot be easily avoided. Sites containing scaffolding can be entirely separated from people, or pedestrians can walk through another road to reach their destination. On a road, sometimes the only other route involves traveling to extreme lengths. Creating easy accessibility for driving through work sites is one way to manage this unavoidable burden. AS 1742.3-2009 addresses this by recommending a competent person, who has been properly trained, to draft a traffic plan and install all signs and devices necessary to guide this procedure. Different scenarios in which this method can be executed are detailed in the standard.
Aside from traffic, provisions should be made for pedestrians, bicyclists, school children, and emergency vehicles. While these should minimize traffic and not limit public transport in any way, they need to retain regular safety conditions for all people. For safety of the workers, the standard recommends placing a barrier between them and oncoming traffic.
AS 1742.3-2009 is part of the Manual for Uniform Traffic Control Devices. Other standards in this include:
AS 1742.1: General introduction and index of signs
AS 1742.2: Traffic control devices for general use
AS 1742.4: Speed controls
AS 1742.5: Street name and community facility name signs
AS 1742.6: Service and tourist signs for motorists
AS 1742.7: Railway crossings
AS 1742.8: Freeways
AS 1742.9: Bicycle facilities
AS 1742.10: Pedestrian control and protectionAS 1742.11: Parking controls
AS1742.12: Bus, transit and truck lanes
AS 1742.13: Local area traffic management
AS 1742.15: Direction signs, information signs and route numbering