Since when do landscapers need to worry about falling?

Let's say you own a landscaping business, you're familiar with green roof technology, and you're thinking of taking it and your employees – literally – to the roof. Have you also thought about a key safety issue facing your employees when they've reached the top?

For the uninitiated, green or eco-roofs – more properly known as vegetated roofs – are thin layers of living vegetation installed on top of conventional flat or sloping roofs. Many of these roofs are installed or maintained by businesses that specialize in green roofs, but traditional landscaping businesses have gotten involved, too.

Most landscapers probably know that Oregon Landscape Contractors Board regulates landscaping work in Oregon. Their jurisdiction includes licensing for installing landscaping on "roofs, walls, and structures and overseeing the installation of green construction elements such as plants and growing media, filters, drainage, aeration mats, and root barriers; the addition of nursery stock and elements to support that which is above the roofing membrane." The licensing exam also includes questions about worker safety, covering equipment, first aid, hazardous substances, and Oregon OSHA.

When do your employees need fall protection?

If your employees are going to be working on rooftops – installing an entire green roof or simply maintaining existing landscaping – you'll need to think about when and how to protect them from falling.

They'll likely need some form of fall protection if they're working on a roof that's 10 or more feet above the next lower level and has unprotected edges. Generally, "unprotected" means a roof edge without guardrails or parapets at least 39 inches high. Your employees also need to be protected from falling into exposed holes and skylights that are six feet or more above lower levels.

The safety requirements for your employees, including fall protection, may be specified by the general contractor if you're installing a green roof as part of a larger construction project. But don't assume that will happen. For example, the contractor might require roofers to set up guardrails around the roof perimeter while they install the roof membrane, but those same roofers might take the guardrails down when their work is done, leaving your employees exposed to falls when they install landscaping. And if there's no general contractor involved, you're on your own. The bottom line: know how to protect your employees when they're working on the roof.

How to protect your employees from falls

It doesn't matter whether your employees are installing a green roof – i.e., installing the landscaping above the membrane – or maintaining landscaping that's already there; they'll need fall protection if they're exposed to falls. If the roof perimeter lacks guardrails or parapets at least 39 inches high, they'll probably need protection. What are the options?

• Personal fall-arrest systems: A personal fall-arrest system consists of an anchorage, connectors, and a full-body harness that work together to stop a fall and minimize the arrest force. Your employees aren't permitted to tie off to anything on the roof that just looks secure; anchorages must support at least 5,000 pounds.
   
• Guardrails: Guardrails consist of a top rail (which must be at least 39 inches high), a midrail, and an intermediate vertical member. Guardrails must be capable of withstanding a 200-pound force applied within two inches of its top edge in any outward or downward direction. Screens and mesh are required when material could fall between the rails.
   
• Restraint systems: Unlike the personal fall-arrest system, which is designed to stop a fall, a restraint system prevents a worker from reaching an unprotected edge. The system consists of an anchorage, connectors, and a body harness or a body belt. The anchorage must support at least 3,000 pounds. Restraint systems may not be practical for those whose work requires them to move about the roof.
   
• Warning lines: A warning line made from rope, wire, or chain can be used to warn employees who are approaching an unprotected roof edge. It must be set up so that it keeps workers at least 10 feet back from the edge and must eliminate the exposure and the risk that a worker could fall over the edge. Oregon OSHA has a fact sheet that describes how to set up the warning line.
   
• Covers for holes: Simple and effective when they're properly installed, rigid covers will prevent your employees from falling through temporary holes and skylight openings in the roof. Covers must support at least twice the maximum expected weight of workers, equipment, and materials. Skylights are not considered covers unless they meet this strength requirement.

You'll find Oregon OSHA's fall protection requirements for general industry work (which includes landscaping) in Subdivision 2/I, Personal Protection Equipment [437-002-0134(5)].

Don't forget training

You can't assume your employees know how to protect themselves from falls, especially if they're working on a roof and using equipment such as personal fall arrest gear for the first time. They'll need to be trained about the hazards at the site so that they recognize them and know how to protect themselves.

As the employer, you can determine how to train your employees; however, the person who does the training must be a competent person – i.e., someone who can identify hazards at the site, who has management authority to control them, and who knows how to use and operate any fall-protection gear that your employees may need.