by Katie Daniel | May 8, 2017 2:49 pm
by Andrew J. Miller, CSI, CDT
In the construction industry, falls are a major cause of workplace-related deaths, responsible for over a third of construction worker fatalities. Of fatal falls occurring between 1992 and 2009, one third total were from roofs, according to a study published in the Journal of Safety Research by the Center for Construction Research and Training (CPWR).
Several factors contribute to roof-related fatalities. A 2010 study in Ergonomics attributes roof falls to:
The study posits task-related, environmental, and personal factors should all be taken into account, in addition to the fall-protection measures employers typically put in place and those sanctioned by the Occupational Safety and Health Administration (OSHA).
OSHA named its standard 1926.501, Fall Protection, as its most frequently cited violation of 2015. (The 10 most frequently cited Occupational Safety and Health Administration (OSHA) standards can be viewed at www.osha.gov/Top_Ten_Standards.html.) Some of this standard’s requirements include:
OSHA updated its penalties for violating these regulations in August 2016. (An updated list of penalties is available at www.osha.gov/penalties.) The mandates are specific and binding, but it is important to note they are general requirements for fall protection systems, and compliance with them does not automatically merit approval from OSHA. Rather, it is independent testing agencies that verify whether employers follow the aforementioned standards.
Among fall protection systems for roof construction, the non-penetrating guardrail is one professionals should consider—not only for its ability to keep workers safe, but also for its potential to minimize general construction-related risks.
There are two types of fall protection systems: active and passive. Understanding what these are, as well as their implications for construction safety, is crucial to devising safety-related specifications.
Active fall protection systems
Active systems depend on the user to be effective. They typically involve tie-off anchors or harnesses—as in the case of personal fall arrest systems—and feature a variety of requirements. For example, tie-off anchors must be able to hold a 2268-kg (500-lb) load at minimum and be certified by a structural engineer. They should also be inspected and recertified on an annual basis, per the regulations covering the area where the project takes place.
Additionally, fall retrieval plans must be implemented so when an accident occurs, the victim can be attended to within a certain timeframe (usually 15 minutes). The earlier the victim is given medical attention, the more likely it is the treatment can take effect and prevent a fatality.
All personnel must also receive adequate training for use of active fall protection systems according to 1926.503, Training Program. This training should cover the types of fall hazards most likely to be encountered by workers, along with the procedures for using, maintaining, and inspecting fall protection systems, the role of every employee in the use of these systems, and the limitations of each type of fall protection equipment.
Employers must verify compliance with this provision by submitting a written certification record for every trained employee. Training documents should also be regularly reviewed and updated. Further, any review of tie-off systems should be done in the presence of the building owner’s environment, health, and safety (EHS) representative.
In OSHA 1926.502(d), Personal Fall Arrest Systems, OSHA sets out standards for such arrest systems. There are two primary points to be aware of:
Even with training, there is still risk inherent in using active fall protection systems. Since individual workers can use these systems as they please, it is possible they will fail to install them correctly and become more susceptible to fall-related injuries or fatalities.
This is not to suggest active fall protection systems should not be used at all. If these systems are the best solution for the project and circumstances at hand, then they should be utilized, with their specifications made as clear and accurate as possible. In fact, it is better if active fall protection systems are used in conjunction with their passive counterparts.
Passive fall protection systems
Passive systems can function without any action from users. Once installed, they protect construction workers for as long as they are up. Passive fall protection systems need little to no maintenance, and even workers with minimal training can install and benefit from them. Non-penetrating guardrails fall under this category, providing numerous advantages.
If penetrative fall protection systems are installed on roofs, employers run the risk of damaging the structure’s integrity and incurring additional, unnecessary costs. Non-penetrating guardrail systems minimize this risk. Given these systems’ ballasts are heavy enough to keep rails in place, but light enough to refrain from penetrating the roof—while meeting OSHA load requirements—non-penetrating guardrails protect both the workers and the structure.
Ease of installation
Non-penetrating guardrails are designed to be assembled and disassembled as needed. Generally, their installation can be summed up in three steps:
The installation’s difficulty depends on the type of guardrail used. If workers need to accommodate uneven surfaces or equipment, individually adjustable rails should be used, though they may take more time and labor to install.
It is easy to transport non-penetrating guardrails from one place to another—a factor making them cost-effective and suitable for multiple construction projects over different locations. Some manufacturers even provide a special tool for this purpose.
Non-penetrating guardrails can be configured according to a project’s needs. This makes them suitable for a variety of buildings, including schools, offices, commercial spaces, government buildings, distribution centers, and manufacturing facilities.
When properly installed, non-penetrating guardrails provide an adequate amount of protection in compliance with OSHA’s guidelines. The qualities allowing them to meet those requirements are the placement of the top rails and mid-rails, the ballasted bases, and rails used as returns or outriggers at each start and end of the run. Rail sections that are used as outriggers stabilize the last portion of the rail section so it meets the 90-kg (200-lb) requirement.
Examining non-penetrating guardrail systems
As their name suggests, non-penetrating guardrails avoid penetration of the structures on which they are installed. They use a ballast or counterweight system to hold the guardrail in place instead of drilled structures.
Non-penetrating guardrails are typically used by maintenance personnel, contractors, inspectors, and workers with similar occupations. However, they are not intended for use with general public systems.
Like all fall protection systems, non-penetrating guardrails have their advantages and limitations. Design/construction professionals should consider:
Outside these concerns, non-penetrating guardrails involves little risk. They can be installed by personnel with only basic training, require minimal maintenance, and tend to be more cost-effective over the long run than their more-permanent counterparts.
Meeting OSHA requirements
Regardless of a fall protection system’s purpose, manufacturer, or other qualities, it must comply with OSHA’s guidelines. This can be ensured in a variety of ways.
These standards are set out under:
They must be included or referenced in the quality assurance section of guardrail specifications. Again, however, they are general requirements, and OSHA is not obligated to approve railings complying with them.
Architectural and owner requirements
In addition to basic safety, contractors should consider architectural intent and owner requirements when installing non-penetrating guardrails. These can include:
1. Areas to be covered
Ideally, fall protection systems should cover an entire roof edge, but as this is not always economically feasible, care must be taken to choose the best areas to protect (e.g. HVAC equipment, ventilation systems, surveillance cameras, and roof drain cleanouts). It is recommended an EHS or safety specialist be enlisted to review the fall protection plan. However, even with an EHS on board, the contractor may still be unclear on where to install guardrails—for instance, if the written specifications indicate the location of the fall protection system, but the drawings do not. If issues like these are not addressed, disagreements can occur between the EHS and contractor, compromising worker safety and wellbeing.
A fall protection system must be compatible with the design intent of the building. For example, the owner of an industrial facility may wish to use a highly visible yellow system to indicate a commitment to safety, while a downtown library with a vegetative roof might require a less obtrusive railing blending into the building’s architecture. There is nothing in OSHA standards denoting a situation where safety yellow is required—manufacturers provide rails in this hue to provide an additional safety element.
3. Placement of roof attachments
The parts attaching the guardrails to the roof must be carefully placed and meet load requirements. An engineering analysis should be conducted to ensure the railing meets OSHA standards.
Compared to permanent rail systems fabricated with metal, ballasted non-penetrating guardrails are less expensive over a long-term period. The type of material should also be considered in relation to the other criteria previously mentioned above. Non-penetrating systems are generally made of steel or cast steel (bases) with either a painted finish or galvanized finish, but at least one manufacturer offers polyvinyl chloride (PVC). Generally, many permanent, fixed-type railings are made from aluminum and some steel. With these types of systems, the railing connections often need to be coped and welded.
Beyond OSHA compliance
Manufacturer specifications and compliance with OSHA standards are not the only considerations for specifying non-penetrating guardrails.
Types of non-penetrating guardrails
Non-penetrating guardrails feature two primary types of railing system: sized rail sections and mechanically assembled systems. Mid-rails are welded on sized rail sections, while mechanically assembled systems use fittings secured by fasteners. Also, sized rail sections are prefabricated from structural steel tubing at fixed lengths ranging from 0.9 to 3 m (3 to 10 ft.). This allows for automated construction and low-cost mass production.
Most applications can be accommodated by these ready-made rails. However, if a construction project requires custom-length sections, some manufacturers offer rails that can be cut and fitted to the desired length. Since sized rail sections have top rails at 1066 mm (42 in.) and mid-rails at 533 mm (21 in.), they comply with the minimum requirements set by OSHA.
Other options for sized rail sections include:
1. Collapsible railings
If contractors wish to keep sized rail sections unobtrusive, collapsible railings are a good option. They have pivot points on each rail leg, making it easy to fold down the rails and keep them out of sight. To maximize fall protection, outriggers are placed at the start and end of collapsible railings’ runs, positioned at 90-degree angles on the ‘danger side’ of each end.
2. Rails with different leg lengths
Sized rail sections with different leg lengths can adjust to different roof heights without interrupting a run.
3. Customizable safety gates
A gate can be installed to allow access into runs and make it easier for workers to move between the sections divided by rails.
4. Adjustable mid-rail
As the name suggests, an adjustable mid-rail can be fitted to accommodate equipment on roof-line ventilation pipes, stairs, and similar areas. This ensures workers are protected even in areas where rail installation would otherwise be difficult.
5. D-rails or finish rails
D-rails’ cantilever finish allows them to butt up against other surfaces smoothly and avoid jutting edges with the potential to cause injuries.
A thorough description of these structural tubings and fabrications should be included when specifying sized rail sections. Any changes in rail type should be accommodated, especially when considering the different stages a construction project will undergo.
Mechanically assembled or fastened systems are constructed onsite with fittings and fasteners. A section of pipe is used as the vertical stanchion, while the horizontal rail is made of several lengths of pipe joined by connection sleeves. Fittings are used to support the horizontal rail at the stanchions.
Some manufacturers offer inclined or curved pipe stanchions in addition to the vertical variety—these allow the rail to be adjusted according to the architectural design of a building, reducing visibility of it from lower sightlines. When specifying mechanically assembled or fastened systems, a description of the pipes and fittings used should be included.
Base support systems
Most non-penetrating guardrails have a base system ballasting the railing. These systems are unique to each manufacturer, so rails from different suppliers cannot be used for the same base. However, a single base can support different rail systems if all are from the same manufacturer.
Bases are the literal backbone of a non-penetrating guardrail system, providing the anchoring mechanism for the rails to meet OSHA’s minimum 90-kg load requirements. They can be manufactured out of cast steel, or can implement PVC pads as a counterbalance.
Bases come in a wide variety of configurations, many of which:
Having knowledge of these types of base support systems makes it possible to specify the application of the base with understanding of how the rails and base connect to each other and how the base can be used to do more than support the rails. (For example, hinge posts can be inserted into the receiver posts, to which self-closing gates can be attached.) Most importantly, the base system best fitting current construction needs can be determined.
For sized rail sections, one important consideration is finish. Most manufacturers offer various solutions for this, although a ‘safety-yellow’ powder-coat finish is considered the standard. Colors matching common roof and trim finishes are also available for a slight upcharge. If the rail section’s finish needs to be matched with non-standard hues, additional matching fees and setup charges may apply.
If an area needs additional corrosion resistance, galvanized finishes are recommended. Specifications outlining both custom paint and galvanized finishes are not uncommon—often, specifiers will list both in the master specifications and forget to remove whichever they are not using. However, custom paint over a galvanized finish is rarely required and is generally not cost-effective.
When custom colors are requested, using sized rail sections is recommended. Mechanically fastened systems can be custom-painted, but because they are cut to fit onsite, galvanized finish is recommended to keep the cuts from showing corrosion. Painting over galvanized finish also requires additional steps in the finishing process, as well as special handling during assembly to avoid scratching the painted surface.
Mechanically assembled or fastened systems are often specified in a galvanized finish due to the work required for the pipes. For bases, a safety-yellow powder-coat finish is most appropriate, as bases are not usually visible. If the base requires corrosion resistance, however, a galvanized finish may also be used.
Layout is one of the areas most often overlooked by architects and specification writers. At the points where non-penetrating guardrails start and end, enough room should be provided for the system to withstand the 90-kg load requirement.
For systems where bases are placed directly under the rail sections, the base runs perpendicular to the leading edge for stabilization of its end. Having a rail outrigger also helps define the ‘safe’ area within the rail section. If the bases are located behind the rail system, components are added to the base to meet the load requirement.
In some instances, outriggers or counterbalancing mechanisms are not required—for instance, when the rail system is ‘closed’ (i.e. when the start and end points are the same) or when the end of the run is directly attached to the building.
Outriggers have the potential to be trip hazards, but most manufacturers use the rail as the element tying the outriggers’ bases to the system, preventing this. Some systems also use counter-balance components that could pose a trip hazard.
Other factors to consider when positioning a rail system include equipment, vents, drains, crickets, seams, and roof undulations on the construction site. The system should be able to accommodate these not only during installation, but also throughout the project’s duration and the life of the building.
Bases should never be positioned on a surface preventing them from staying flat, like seams and crickets. This is especially important with non-penetrating guardrails, which can be derailed if their location is unable to physically support them.
If other concerns arise regarding how a system should be laid out, it is best to contact the manufacturer for assistance.
Even with OSHA’s tightened standards, falls continue to be one of the leading causes of fatalities in construction. Thus, every stakeholder in the industry—including contractors, workers, engineers, architects, specification writers, and safety specialists—must devise ways to keep fall-related hazards at a minimum.
Non-penetrating guardrails are a strong contender among the many possible solutions to fall-related fatalities. When using this method, type should be chosen according to the project and the specific circumstances, and the system’s capabilities and limitations should be carefully weighed.
|The following list shows factors to be included in non-penetrating guardrail system specifications, with examples in parentheses to give readers a clearer idea of how such specifications can be written.
1. Reference standards.
2. Structural load.
3. Rail height.
4. Rail material and construction.
5. Support base material and construction.
6. Receiver post.
9. Surface protection pads.
In most cases, guardrails comprise only a short descriptive paragraph of specifications. It is hoped emphasizing the importance of choosing the right guardrail and demonstrating what a full specifications guide for guardrails can look like will facilitate creation of a separate section for guardrails, to be used in future specifications.
Where to write specifications
Non-penetrating guardrails are made of metal or PVC, so it might seem the most logical course of action is to place them under Division 05. On the other hand, they are temporary implements on roofs, so placing them under Division 11 or Division 07 (specifically, 07 72 00) is a sound idea, too.
The railings referred to in this article can be used either as temporary railings (i.e. for occasional use while working on a roof, or for protecting openings) or—more commonly—permanently placed railings for industry applications. Railings used during construction could meet the requirements of Division 01 at the discretion of the contractor.
Ultimately, where the specifications should be written depends on how the architect feels the product has been used on the project. This is why it is important to ensure adequate communication between the parties involved—this way, misunderstandings and, more importantly, safety hazards to workers can be avoided or minimized.
Andrew J. Miller is the founder and president of Dakota Safety, which specializes in passive fall protection systems and safety products. He is an active member of the Minneapolis St. Paul Chapter of CSI and has more than 30 years of experience in construction product representation, sales, and marketing. Miller can be reached via e-mail at email@example.com.
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