Tower rescue presents a completely different level of difficulty in planning and methodology. Whether 250-ft communications or transmission towers, they are often necessarily placed in remote areas, and usually inaccessible to conventional paramedic rescue vehicles. While it is each individual employer’s responsibility to make their own determinations on how rescues will be accomplished, the following may help in preplanning for these unusual rescue situations. Pre-planning for rescue in these situations must answer several questions.
911 plays a key role in surviving serious injuries on the job. If crews do not have direct radio communications with a phone-equipped dispatcher, cell service will be the most likely mode of communications in an emergency. And, while most providers have coverage maps available on their web sites, tower rescue planning should include driving the right-of-way to assure that communications is viable.
If working with helicopters to affect a tower rescue in construction or maintenance operations, pilots in the air have fairly good line-of-site radio communications with tower air controllers. The pilot can route calls via FAA towers to 911. In some cases, the helicopter may be too far from a tower for radio communications, but it only takes a few minutes of flight time to get back in range. Be sure to include helicopter crews in pre-work discussion of emergency procedures. If they are available they can be a key component of the rescue plan.
Locating the Remote Accident Scene
911 is an effective system, but some pre-planning through local providers may be needed. When planning, call 911 or the local county EMS and explain what your needs are. Find out if the typical dispatch protocol of the 911 system will be able to meet the need of a remote right-of-way rescue.
The most effective location method is an established numerical rendezvous address for 911 even if the numerical address is remote from the incident site. Crew members can then be deployed to meet the rescuers at that numerical address and guide them to the tower location.
Air rescue services will be equipped with land-based coordinate guidance systems. The pilot dials a coordinate into the system by longitude and latitude and the guidance system points the way. If each tower location does not have a ground- based coordinate location, an effective method is to have a “wilderness type” GPS available. These types of GPS are used by hunters and wilderness hikers to show their current position in land-based coordinates. Be careful to have the proper mode of coordinates displayed. Some GPS units default display in longitude and latitude while others may display in the international UTMG. Basic GPS and longitude and latitude coordinates should be taught in job-site safety training when these methods are used.
While You Wait
To professional rescuers, tower rescue is considered one of the most challenging scenarios. Even if it is possible for a system operator to “dump” a transmission line, parallel circuits in corridors assures that the line will still be dangerously energized through induction. Rescue planning, except where lines were grounded for personal protection, must assume energized conditions. A line crew trained in rescue rigging can be ready for immediate extraction without the need to wait for a team.
Blunt traumatic injuries require a special type of consideration when removing workers from a tower. A person with broken legs, for example, cannot be lowered through the maze of cross braces in a climbing harness. Rescuers must rig for rescue with a focus on effective delivery for treatment without causing further injury. High-angle rescue immobilization is accomplished using a collapsible stretcher known by its trade name as a SKED. If an injured worker can be “SKED rigged” before emergency personnel arrive or if crews can assist emergency personnel in rigging the SKED, the rescue can be much more timely. There are companies across the U.S. that specialize in training high-angle rescue and SKED rigging, several even specialize in electrical towers. SKEDS are not expensive and fit in a 36- by 9-inch roll. Learn more at www.skedco.com/documents/sked_instruction.pdf.
Rigging for Lowering
The drop from a tower is likely to exceed 125 feet, so rope and rigging are important considerations when planning for rescue. In most cases standard fall-arrest body harnesses such as those used in a bucket truck are not sufficient for tower work. Tower climbers should be wearing harnesses with pelvis loops and work poisoning D-rings as well as chest and dorsal loops to provide for several configurations of fall prevention and rescue rigging.
In typical rescue models, a line worker would rig a hand line rope—half wrapped over brackets or arms for descent speed control—to lower an injured worker. Work ropes rigged over tower steel for control of descent are not appropriate for the long drop of a high-angle rescue. Besides the weight of the rope, running a typical three strand poly work rope over a structural member will produce excessive heat and uneven stresses that will cause the rope to “knot-up” ahead of the steel before the injured person reaches the ground.
A Rescue-8 device used in rappelling and by high-angle rescue teams will provide braking control and at the same time protect a rope’s mechanical integrity and safely dissipate heat and stress on the rope while running under load. A tower crew should have a rope bag that includes at least 200 feet of 11mm diameter kernmantle type “static” rope, which has limited stretch for improved control of the rigged descent. Static ropes are used by high-angle rescue teams because they are low stretch and of sufficient strength to accomplish the task without knotting up or failing.
Rescue Rope Care
Static rescue ropes should be stored in a “fake-bag” for easy access and to protect them from the elements. Faking a rope is a rappel term that refers to zig-zag folding of a rope into a storage bag for reliable deployment. Inexpensive nylon backpacks make excellent fake-bags. Rescuers typically pull out the leading end of the rope, and after running the end through the rescue rigging, the bag can be dropped, cleanly deploying the rope.
When we think of aerial rescue, most likely our first thought is about the best way to get an injured worker down. When it comes to tower rescue, however, the method is only a small part of the planning. iP
Jim Vaughn is a Safety Supervisor with MYR Group’s Sturgeon Electric in the Arizona/New Mexico Line Division. As a former lineman with 20 years of transmission and distribution construction and maintenance
experience with both contractors, IOUs and Co-ops, his past 15 years have been dedicated to safety and training in the line industry. Jim has education related degrees from Baptist College and Georgia Tech, Safety, MYR Group/Sturgeon Electric and Arizona-New Mexico Line Department.
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