Maintaining a wind turbine often means working at heights exceeding 300 feet. Although a tool falling from any height is a problem, in the case of wind-power maintenance, an object falling several hundred feet endangers everything and everyone below. It is a site safety issue. A large, free-falling tool, such as a torque wrench, could kill someone. If it hits a blade or lands on a pump or bearing, the falling tool will do significant damage and cost a company in productivity, workmen’s compensation claims, medical bills, and equipment repairs.
Tool tethers are the best way to protect employees, their tools, and the work site. When the tool, employee, and application are correctly mated, working aloft becomes easier and more efficient. The safety engineer’s goal in correct Description: tethering procedures is to make sure the tool, application, and recoil-retraction force are in balance. When the tool is extended for use, only minimal force should be necessary so as not to cause worker fatigue or, in the reverse, a ”kick” when retracted. A tool is correctly tethered when its storage or use minimizes the dangers of entanglement, fatigue, and annoyance, and maximizes worker satisfaction and output.
A new safety engineer may ask: How do I know which type of tether to use in each application? There are at least three: retractable tool tether, coiled, or lanyard. That engineer may also wonder: Should the tether be attached to the worker or anchored to the structure? Do you need a quick release device to safely change out tools?
It can seem overwhelming, but when a tether is correctly matched with a tool, worker, and application, the work is safer, easier, and more efficient. Conversely, a poorly matched tether can become a safety hazard. The safety engineer’s challenge is to provide a tether that is user-friendly and appropriate for the work environment. The following overview describes a few tool and instrument-tethering options.
One size does not fit all
With such a high risk to workers’ safety, it’s unfortunate that little has been published on the subject of tethering equipment and tethering safety techniques. Many safety professionals are unaware of the available options. And most companies that sell safety equipment or personal fall-arrest systems fill their product line by importing a basic tether in two or three sizes. When tool tethers are ordered without specifications beyond the weight of the tool, chances are good the tether may not be appropriate.
In reality, safety engineers have thousands of choices from U.S. manufacturers specializing in tool, gear, and instrument tethers. Tethering systems can be specified for a variety of applications in a broad range of industries. Each application has its own set of criteria, such as standing up to saltwater, chlorine exposure, and high temperatures, or special mounting or attachment needs. Manufacturers like Hammerhead Industries Inc. and Snap-on Tool’s (snapon.com ), with its Tools-at-Height program, are addressing the importance of selecting a proper tether.
An appropriate lanyard and tether for each application
The objective of tethering is to secure tools to prevent injury and damage. But there are factors that may impact the safety of the worker using the tether or lanyard. An improperly mated tool and lanyard can inherently lead to lower productivity and exposure to injury. When the tethering device limits mobility, recoils too fast, or exerts too much resistance on extension, it can often backlash on workers. The general result is fatigue, annoyance, and often non-compliance in lanyard use.
The correct design philosophy is to provide a lanyard that has a low-stretch force. This helps eliminate or reduce user fatigue when it is at full extension and providing the proper amount of recoil. This is accomplished by sewing the elastic material inside the webbing during manufacturing instead of assembling it after the fact. In this manner, the elastic provides optimum retraction tension and low stretch force.
Tethers heavier tools to a structure–not a person
Tethering heavy tools, (generally over 5 lb) to a person is a significant safety concern. Instead, safety engineers should consider using anchor tethers. Anchored tethering transfers the shock load from by a dropped tool to the structure and not that worker. For heavier tools (over 10 lb), structure anchoring should be mandatory.
For tools less than 2 lb
Picture a worker using several small tools, say an electrician using screw drivers, pliers, and an amp meter. These tools and working conditions are poor choices for coil tethers or lanyards. But they are ideal for a retractable tether that safely permits attaching multiple tools to the worker with almost no risk of entanglement or snagging. Tool and gear retractable-tethering devices offer hundred’s of combinations of mounting systems, line technology, and shock-absorbing capabilities.
Quick-release fittings for several tools on a tether
Change the tool not the tether. A single-tool lanyard is sufficient when one tool is the only thing tethered. But what do you do when you have multiple tools to tether? It’s a common scenario. There are many options for worker safety in multi-tool tethering situations. Quick-Connect tethers offer easy tool change-out and are available in a large selection.
Unfortunately, there are none. Tool-tether ratings have not been established or standardized by either the tethering or safety industries. There are no universal specifications governing tool tethers as there are with fall-protection devices. As such, the safety engineer has no real basis for choosing proper tethers and thus arbitrarily makes a selection based on tool weight. Without additional specs, the safety engineer maybe creating a potentially dangerous situation.
Of greater concern is how some suppliers arbitrarily rate their lanyards so they meet customer’s requests. For example, when a safety engineer requests a tether for a 3-lb tool, the distributor may offer to send one rated for up to 15 lbs, for a higher safety margin. Although both supplier and buyer have good intentions, they may be setting up a potentially hazardous situation. For instance, using a tether rated for a much heavier tool will not operate effectively because its stretch and recoil are considerably out of scale for the lighter tool. The more serious problem is when a worker, assuming a lanyard is rated for 15 lbs, thinks he can connect a 15-lb tool to his tool belt. That’s a bad idea. The 15-lb tool, at a full-drop length, will generate in excess of 250 lbs of shock load, more than enough to knock a worker off his perch. A personal fall-protection device may not further protect that person. Safety engineers should explore practical tool tethering solutions with reputable manufacturers.
Make the employee your partner in tethering
For a successful tool and instrument tethering-safety program, employees and safety engineers must partner. A properly tethered tool or instrument makes work more efficient. It simplifies every repair, maintenance, or manufacturing project by keeping workers’ tools handy and accessible. Tethers that correctly complement the tool, worker, and application are conductive to advocates rather than antagonists.
Filed Under: Construction, News, Safety, Towers