Parapets Are an Important Safety Measure for Fall Protection and Prevention
We often hear the word “parapets” when referring to architectural features on buildings. A parapet wall is defined as a dwarf wall or heavy railing around the edge of a roof, balcony, terrace, or stairway designed to prevent individuals behind it from falling over the side..
While often meant for design purposes, parapet walls play an important function when it comes to preventing falls both during construction and after, when maintenance or other personnel are required to access the rooftop.
Parapet Walls Help Prevent Falls
Construction and maintenance workers often come close to roof edges and can be exposed to fall hazards when accessing building roofs during construction and for operation and maintenance tasks after the building has been completed.
The OSHA Fall Protection regulation for construction (29 CFR 1926 Subpart M) requires fall protection be provided whenever a worker is exposed to a fall 6 feet or more above a lower level. Fall protection can be provided in the form of guardrails, safety nets, or personal fall arrest systems. A parapet wall acts as a guardrail when it meets the guardrail requirements outlined in the standard (29 CFR 1926.502(b)). The top rail of a guardrail system must be 42 inches high, +/- 3 inches. Therefore, a parapet wall must be at least 39 inches in height to be considered adequate fall protection during construction.
Watch Compliance Consultants, Inc.’s CEO, Terri Collins, show a real-life example of an OSHA compliant parapet wall on the roof of a construction site.
Additional Parapet Design Options
Parapets do not necessarily have to be constructed walls. There are several options for creating a rooftop parapet barrier.
One such system is a parapet wall clamping rail which grips the existing parapet.
Guardian: Parapet Clamp for Guard Rail Systems
Prefabricated powder coated or galvanized steel railings slide into receiving posts and are tightened to the existing structure. This is a great solution if your existing parapet wall does not reach the minimum 39-inch height requirement.
This type of parapet fall protection system can be used as a temporary or permanent roof fall protection system. Furthermore, the installation of this parapet wall clamping product provides needed fall protection for an OSHA compliant workspace.
Interim Design Solutions for Construction
Typically, the decision to add parapets or to extend the height of a planned parapet is made during the conceptual design of a building.
Since workers often need to access the rooftop during construction of a building, they can be exposed to fall hazards before parapets can be completed.
During this time, the following interim measures may be needed to protect workers from falls:
- Job-built or commercially available guardrails that meet OSHA height and strength requirements
- Properly designed anchor points with appropriate personal fall arrest or restraint systems
- Safety nets
- Warning line systems
After parapets are finished, they can serve as fall protection for the remainder of the building construction. They are considered to be a passive fall protection system, meaning workers are protected without the need for additional action.
Prevention Through Design
Safety professionals regularly think about hazard mitigation by using the hierarchy of controls.
Here is a chart for the Hierarchy of Controls
Elimination of a hazard is the most effective means at our disposal. While we can’t keep construction and maintenance workers on the ground at all times, we can think in terms of isolating them from the hazard through the use of engineering controls. A parapet wall that meets OSHA’s height and strength requirements of a guardrail system is one such engineering control.
Thinking about fall prevention at the design stage is critical. Designers, architects, and engineers should work collaboratively, thinking not only about the end user of the space, but also how to protect workers during construction and future maintenance personnel as well. Think ahead and consider all potential upcoming needs, conditions, and uses, and design accordingly.
Additional considerations should also be taken into account to prevent falls from rooftops:
- Ensure that the parapet can withstand a force of at least 200 lbs.
- Install a capstone over masonry parapet walls to prevent cracks from water
- Consider the design of drainage systems, roof access, and insulation to accommodate parapets
- Plan ahead for other uses for parapets during the design stage, such as anchorage for personal fall arrest systems and support for window-washing
- Ensure that the parapet has the same fire rating as the wall below
- Thoroughly evaluate snow loading and roof ponding loads when considering a parapet wall. Additional roof loading may require re-design or extensive modifications to the roof structure. Consult local building codes.
Cost Savings Potential of Parapets
The use of parapets can save costs in several ways. Parapets may increase the overall costs of the project for things such as labor and additional materials, but most often these costs can be offset over the lifetime of the building.
Additionally, the potential of an injury or even death and possible ensuing OSHA citations and lawsuits are mitigated or avoided, potentially saving hundreds of thousands of dollars, or being put out of business.
Parapets allow for greater use of overall roof top space. By eliminating a 15-foot setback from the roof edge for things like vents, access and equipment workers have a safe space in which to operate. It is recommended that equipment, vents, access points, etc., be placed 15 feet back from the roof edge to reduce the risk of falling during servicing and maintenance. This would no longer be necessary if parapets are installed.
If properly designed (39-inch or taller) parapets are in place, fall restraint systems would no longer be needed for maintenance work within the perimeter of the parapet.
However, fall protection would still be required for work on roof-top equipment/design features at heights greater than 6 feet, over the edge of the parapet, on the face of the building, and for work near unguarded roof openings and skylights.
Parapets Are a First Line of Fall Protection – Know the Requirements
Parapets are worth their additional costs but they must be done correctly to provide the necessary fall protection for rooftop workers. Don’t take shortcuts or guesses on what you need to protect your workers during and after construction.
Interested in learning more about preventing falls on your jobsite? Compliance Consultants, Inc. can walk through your site and consult with you to identify possible solutions.
Contact Us Today to Get Started!
Resources:
https://www.osha.gov/laws-regs/regulations/standardnumber/1926/1926.502
CDC:
https://www.cdc.gov/niosh/docs/2014-108/pdfs/2014-108.pdf
(This document is in the public domain and may be freely copied or reprinted. NIOSH encourages all readers of the Workplace Design Solutions to make them available to all interested employers and workers.)
