Published on: April 22, 2020
We often have customers ask us to put a lifeline or a guardrail on their roof to protect their employees and contractors. Both lifelines and guardrails can be an effective means to protect people working at height and each has its’ place and purpose. In this article we will be evaluating the criteria and considerations when deciding on which of these options to use on a roof. Asking the question if a lifeline or guardrail is best for a roof however is a bit of putting the cart before the horse. Before we can discover which is best there a bit of work to be done first.
Step 1 – Fall Hazard Survey
Your fist step should be to evaluate the risks and exposures to the employees and contractors on the roof. ANSI Z359.2 – Minimum Requirement for a Comprehensive Managed Fall Protection Program provides excellent guidance on how to perform and prepare a fall hazard survey report. Some of the criteria that are included in this survey are:
- Identifying all work tasks that expose workers to a fall.
- Evaluating Environmental factors that may increase the risk of falling. This is important for roofs as there are factors such as lighting (work at night), heat and ice that should be considered.
- Identification of work paths taken to and from the hazard area
- Risk ranking of the hazards based on frequency, risk of falling and severity of injury.
- This report will also commonly include recommendations on hazard abatement options.
Step 2 – Understand what OSHA requires
In 2017 OSHA provided a major update the general industry fall protection standard and provided much more clarity on what is required for fall protection on roofs, especially flat or low sloped roofs. Here is a summary of those requirements as they relate to roofs
- High Sloped Roofs – If a worker is on a roof with a slope or pitch greater than 4 on 12 he must be tied off. 4 on 12 means that for every 1 foot or 12 inches the roof pitch increases by 4 inches. Guardrails do not provide an adequate means of protection as the worker may slide through the railing. One option to consider on high sloped roofs to get away from tying off would be pitch corrected walkways with guardrails to provide a level working walking surface.
- Low Sloped or Flat Roofs – This one can get a little confusing. First determine if the work is both temporary and infrequent. Most tasks on a roof like changing a filter or replacing a motor would be considered temporary and infrequent. If the work is frequent or a permanent task the uses of a work rule described below is not allowed. The following is assuming that the work is both temporary and infrequent:
- 0’-6’ – Work that takes place at the edge or within 6’ of the edge requires a guardrail, safety net or tie off.
- 6’-15’ – Work between 6’ and 15’ requires the same as above and we can also include the use of a warning line set a minimum of 6’ from the edge.
- 15’+ – For work 15’ or farther from the edge of the roof we can use all of the above options and also allow for a work rule that requires workers to stay more than 15’ from the edge and no fall protection is required. The work rule would be a written administrative control measure where no fall protection is required.
- Other Considerations – The edge of the roof is not the only fall hazards we face on a roof. We are also required to:
- Protect ladder access points with self-closing gates
- Protect the area where a ladder is accessed from the roof if there is no parapet or the parapet is less than 42”
- Protect roof hatch access point with guardrails and gates.
- Protect from falls through skylights on the roof.
- Provide a safe means to crossover obstacles on the roof.
- Provide walk pads if there are slippery surfaces.
Now that we have evaluated the work tasks and fall hazards that exist on the roof and we understand what OSHA requires we can begin to think about what the best solution to the problem might be.
Step 3 – The Hierarchy of Controls
When evaluating fall hazards we should try to implement solutions higher in the hierarchy of controls first. What are the controls?
- Eliminate the hazard – This is best done during building design by minimizing the amount of equipment on the roof or increasing parapet heights to greater than 42” to act as a guardrail. The question we need to ask is can we eliminate the work task or relocate equipment to eliminate the need for workers to have to access the roof? One example we have seen is companies have elected as they replace old A/C units to install new ones at the ground level.
- Provide a means of passive protection – A guardrail is a good example of a passive means of fall protection. The worker doesn’t have to do anything or think about anything to be protected.
Provide a means of active restraint – Active restraint are tie off systems, often lifelines that are positioned a set distance, usually 15’ away for the edge and with use of length limited lanyard prevent the worker from falling when tied off. - Provide a means of active arrest – Active arrest fall protection systems will allow the user to fall and then arrest the fall once it occurs. The reason this is less preferred is obvious and many owners of active arrest systems overlook the complexities of these systems. Training is imperative. A rescue plan that works and can get the worker down in under 15 minutes is also critical.
- Administrative Controls – The work rule described above is an example of an administrative control. They should be a last resort and rely heavily on enforcement, acceptance and the worker doing the correct behaviors.
Step 4 – Picking the right solution
Now that we have identified the hazards, know what OSHA requires and the priority of the types of controls we should implement we can decide which is the best solution. Invariably, there are usually several options when it comes to solving a roof fall hazard issue and a lot of factors to consider. Here are the Pros, Cons and other factors to weigh when considering either a lifeline or guardrail for a roof.
Horizontal Lifeline
Pros
- Cost – Usually less expensive. Depending on layout and configuration it can be about 30% – 50% less than similar protection provided by guardrails. This is usually only the case with longer runs of lifelines. Much of the cost is in the end components.
- Less Visible – If aesthetics is important, lifelines are typically not visible from the ground.
- High Sloped Roofs – Can be used on high pitched roofs over 4/12
- Less dead load – on the roof. While a lifeline doesn’t add much weight the roof, the roof must be capable of support the required loads in a fall or for restraint.
- “Falls Through The Roof” – Can provide “fall through the roof” protection. We see this as a concern on some of the older more fragile asbestos type roofs.
- Less Materials to lift to the roof – Some roofs are very difficult to access with lifting equipment and lifeline materials can often be hauled up by hand, if required.
- Durability – Often made of stainless and/or galvanized components. A properly maintained horizontal lifeline can be expected to last for 25+ years of use.
Cons
- Roof Penetration – Typically requires roof penetration. More holes in the roof means more places a leak can occur. There are non-penetrating options available but are only realistically practical for standing seam roofs.
- Engineering – A qualified engineer must perform a structural analysis of the building to ensure the roof can support the loads imparted during a fall event. If you don’t have good structural building drawings this can be expensive.
- Training – Users must be authorized and trained on how to use the lifeline.
- Inspection – Requires an annual inspection by a competent person. This is typically done by the supplying fall protection company and can range from $1,500 to $3,500 a year.
- Installation – Horizontal Lifelines must be installed by trained and qualified technicians. A properly installed lifeline will be certified and tested in accordance with manufacturer and the designing engineers’ requirements.
- Recertification – Every 5 years the lifeline must be recertified by a qualified engineer. Depending on the quality and detail of the original design work this can range from $2,000 to $5,000 or more.
- Rescue – Requires a rescue plan to provide prompt rescue. You can not rely on calling 911. A rescue plan, equipment, training and retraining is time consuming and costly.
- Prone to Misuse – Is the harness being worn properly? Did they inspect prior to use? Are they using the right lanyards? Are they using the equipment correctly? All questions we need to be able to answer and are unfortunately common areas of misuse.
- Re roofing – In our experience, if a roof is going to be replaced the lifeline will likely get damaged because someone placed a pallet on the cable or got tar or overspray on the components.
Guardrails
Pros
- Viable Non-Penetrating Options – There are lots of options available for non-penetrating roof guardrail solutions. There are a few non penetrating lifeline options available as well, but are not nearly as practical in cost and application as guardrails. A word of caution here. Give careful consideration toward using a galvanized material finish at a minimum for guardrails. In our experience, yellow painted guardrails fade quickly and require frequent touch up and periodic repainting. If colored guard rail is required, consider powder coated color on top of galvanized. Costs a little more upfront but worth it long term.
- Idiot Proof – Short of someone climbing over the railing, there isn’t much risk of misuse and no additional training is required.
- Configurability – Lifelines work best with long straight runs. If we start adding a lot of corners, bends or obstructions it gets expensive and difficult to install and design. Guardrails, especially modular style ones using fittings are easy to configure around obstructions and corners.
Cons
- Aesthetics – If beauty is important or there are regulations sometime associated with historical buildings then guardrail might be a challenge. There are things that can be done to make a guardrail more appealing to the eye or less visible. The uprights can be leaned in towards the roof or curved. The railing can be coated to a specific color or infill panels can be added to give more visual appeal.Note: OSHA compliant guardrails are not designed to protect the general public. If your roof has a patio or space accessible by the public, specifically children, you must design the guard rail to also meet international building codes.
- Weight – Guardrails, especially those with weighted bases are heavy and add a lot of load to your roof. Typically, this load is applied near the edges of the roof where it is strongest, and the extra weight is not a concern. However, if there is any doubt an engineer should take a look at the additional loads and make sure the building can support them.
- Cost – The upfront cost of a guard, especially a ballasted or freestanding version can be high. The long-term cost of ownership versus a lifeline however will typically even out over the lifespan of the product. If your building has a parapet, you might consider saving costs by attaching a guardrail to the parapet. This works well on the outside of tilt wall or concrete buildings but is generally avoided if it requires any penetration of the roof material. On metal roof both lifelines and guardrails can be attached with similar methods involving S5! Clamps or rivets depending on the style of roof.
- Conclusion – If you can’t eliminate the need to get on a roof and the roof is flat or low sloped, guardrail or guardrail in conjunction with warning line should be your go to option. In special circumstances lifelines may be used, but careful consideration should be given to the added risk and recurring costs associated with them. On a high sloped roof, horizontal lifelines will likely be the best option, unless access can be provided by means of pitch corrected walkways with guardrails. We highly recommend using an industry expert to help you perform a fall hazard survey of your roof and follow the steps laid out here to provide a total roof fall hazard protection solution.