Performing their duties at-height in wind towers over 100 meters, it isn’t of a matter of if, but when tower technicians may be in need of rescue.
Falls, slips and trips, falling objects, electrical and mechanical issues, the fitness of workers, and weather conditions are all hazards that can play a part in accidents that may occur when working in and around wind turbines. Being well prepared and thinking through such scenarios in advance may make the difference between life and death.
The Occupational Safety and Health Administration (OSHA) requires that employers provide for “prompt rescue in the event of a fall or assure that employees are able to rescue themselves” to prevent the potential for suspension trauma. ANSI Z359.2-2007 also has guidance on rescue requirements, procedures and training that employers need to implement in their safety programs.
What Role Does Training Play in Being Prepared?
Accidents are bound to happen, but how workers react in such scenarios makes all the difference. Training is proven to substantially reduce workplace accidents. This should make ongoing training a high priority for maintenance crews.
Experience is always beneficial; however, when it’s based on poor work practices, comes from a poorly trained source, or results from the passing down of information that isn’t current with the most recent standards, experience can actually be a detriment to safe rescues. Staying up-to-date with current practices and standards is vital to ensuring workers are well-prepared in the event of an emergency.
Common Rescue Scenarios to Train and Prepare For
Here are some common rescue scenarios that can occur while working on wind towers:
1) Rescue from the ladder inside the tower which provides climbing access to the nacelle:
Although maintenance work is usually not performed on the ladders after the tower has been constructed, they provide workers with a means of access to the nacelle. That poses a potential threat to worker safety. This involves climbing to great heights, usually multiple times a day. Even though the climber can use the deck landings to rest, this climb can still be physically demanding, leading to cramping, fatigue, heat and cold stress, and more.
Other hazards in this scenario include slipping on an oily or muddy ladder, as well as the constant threat of items such as radios, cell phone and hardhats which can be dropped or fall, striking workers below.
Ladder rescues in this situation are challenging and must be planned from both the ground and from the nacelle. The size and portability of a complete rescue system is crucial, as it must be deployed and carried to the victim from the ground or down the ladder if it’s stored in the nacelle.
2) Rescue from the top of the nacelle roof
This scenario can occur if an emergency happens while working on top of the nacelle or if the worker slips while moving on the nacelle, possibly while trying to access the hub.
Non-entry fall protection rescue is reserved for injured workers who are suspended by fall protection, but are conscious, alert and can adequately protect themselves during a lowering operation. To perform such a rescue, the rescuer must have access to the victim’s anchor point, integrated lanyard rescue D-ring or harness D-ring.
It’s also possible that the victim in such a situation may be injured or unconscious on top of the nacelle. In this case, it would be necessary to lower the victim over the edge of the nacelle. In cases where victims fall over the side, there may be a need to pick them up off of their fall protection equipment.
Challenges in this rescue scenario include deploying and carrying the entire rescue system to the top of the nacelle. Normally, the rescue equipment would be stored there, but there’s still a need to get all the equipment through the top hatch to the top of the nacelle.
3) Rescue from inside the nacelle:
This scenario may occur at any time, as the worker is likely to be working inside the nacelle most of the time. Workers can encounter electrical hazards, sustain injuries from working on the heavy equipment, or experience medical conditions that leave them incapacitated.
This rescue may be challenging because the employee may be working under or around equipment away from the escape hatch. Further, the employee will likely be working without a fall protection harness. There may also be a need to lift the technician up from where he’s working, which may be down below the turbine housing or on the opposite end of the nacelle from the escape hatch. Putting the victim’s harness onto him is imperative to complete the rescue.
The victim must also be transported from his location, up over equipment to the escape hatch. Cross haul techniques are best used for this to allow a single person to perform the rescue. Multiple lifting systems make this process very simple and efficient. Pulley systems should be carefully monitored while in use. If increased resistance occurs during the process, operations should cease to check the victim for a trapped body part or equipment.
4) Rescue from inside the hub:
When a worker is inside the hub, rescue may be challenging, particularly if the rescue system is stored in the nacelle as it must be deployed and carried to the victim. Anchoring to pick the victim up may also prove difficult, meaning cross haul techniques must be used to move the victim’s body up and diagonally out of the hub. Multiple lifting systems make this process feasible.
The hub is a very dirty, greasy environment, so it’s important to ensure that the rescue system is not significantly affected by possible contamination.
5) Self escape in case of an emergency:
Emergency scenarios can occur when a worker may need to escape the nacelle to ensure his own safety. The hazard from which a worker may need to escape affects the choice of the escape point. If there’s significant heat in the nacelle the worker may be under major duress. In this case, ensure the rescue system operates with fire resistant rope.
Designing Effective Plans Before You Need Them
Designing effective rescue plans for each of these scenarios is critical to successful rescues. Rescue plans should include careful consideration of:
• Time, casualty management and first responder/medical help
• Direction of EMS to site/casualty or a central pick-up point
• Weather reports and site map made available to all employees and contractors on site
• Supplying local EMS with map coordinates of towers
• Clear marking of towers
• Arrangements for workers to direct EMS to accident tower site
• Drills involving EMS and tower hazards awareness. For example: Helicopter paramedics guided to a ground landing zone using green flares so as to avoid confusion with red FAA lighting
Proper planning can make a real difference in successfully rescuing workers when an accident occurs.
Putting it Into Action
The ultimate test of any rescue plan is in the execution. Of course, repetitive training is the key to ensuring workers take the correct actions when a real emergency occurs. Basic guidelines for responding to any rescue scenario always include:
• Don’t put yourself in danger
• Assess the situation
• Raise the alarm
• Now, begin the rescue
A well-developed plan, effective training and a step-by-step approach to executing a rescue all increase the likelihood of positive outcomes when rescue emergencies occur.
Impact Access LLC, Part of the MaxGear Group