Aerials: Safety around powerlines
Firefighters being electrocuted by a powerline while on an aerial device is largely preventable; make sure your department is taking these safety steps
The recent tragedy in Campbellsville, Ky. that injured four firefighters, one critically, underscores the great care that must be exercised when operating aerial devices — and all ladders as well — near energized electrical lines.
All fire departments should use this incident to review their standard operating guidelines and training processes regarding the use of aerial devices in close proximity to energized power lines to avoid these preventable events in the future.
This latest incident is not without precedence. On Jan. 6, 2008, a 40-year-old male career fire captain was electrocuted after coming into contact with a 12,400-volt overhead powerline.
The victim and a firefighter had been assigned to ventilate an apartment building roof and were using an elevating platform fire apparatus to gain access to the roof. The victim was in the process of maneuvering the platform beneath a three-phase powerline when he contacted one of the lines with his neck and back.
The Centers for Disease Control's National Institute of Occupational Safety and Health investigated and reported on this incident. In their May 11, 2009 report, NIOSH investigators concluded that to minimize the risk of similar occurrences fire departments follow these six steps.
- Develop, implement and enforce written SOGs or SOPs for all aspects of firefighting operations, including procedures for working in proximity to overhead powerlines.
- Maintain a distance of at least 10 feet (3 m) between aerial devices and overhead powerlines.
- Use an incident safety officer, independent from the incident commander, when incidents escalate in size and complexity.
- Ensure that firefighters receive periodic safety training specific to all tasks they are expected to perform. The report goes on to specify safety training for operating aerial apparatus near energized powerlines.
- Use of proximity warning devices to detect electrical current when working near exposed potentially energized parts as a secondary means of protection.
- Follow apparatus manufacturer's safety warnings.
There have likely been similar incidents and near misses since 2008. In the intervening six years, what have we learned about safely operating aerial devices in close proximity to energized powerlines? And most importantly, how will our behaviors change so that preventable accidents like these do not happen in the future?
In a 1994 NIOSH Alert: "Preventing Injuries and Deaths of Fire Fighters," NIOSH identified the need for fire departments to establish and follow firefighting policies and procedures. The document further stated that fire departments should develop, fully implement, and enforce guidelines and procedures to be effective.
The alert went on to state that periodic refresher training should be provided to assist firefighters in remembering and understanding departmental SOGs or SOPs.
How often do you and the members of your team conduct initial and refresher training for all of the potential hazards that exist in your community?
Returning to contents of the 2009 NIOSH fatality report, the authors stated that fire department SOGs or SOPs should include hazardous energy control procedures.
The risk associated with operating aerial devices in proximity to energized powerlines is not limited to direct contact between the aerial device or personnel and the energized powerline.
The electrostatic field that extends from any alternating-current powerline is equally capable of energizing the aerial device or causing injury to personnel. This was the circumstance in the Campbellsville incident.
According to NIOSH, proximity warning devices provide audible and visual warning signals to alert the operator and attendant or ground personnel when the boom comes within the proximity of an energized high-voltage power line. These devices can help verify that lines are de-energized. However, they should not be relied upon as the sole or primary means of verifying whether powerlines are de-energized.
Any fire department's SOGs or SOPs regarding hazardous energy control procedures should include the use of AC detectors to verify that powerlines are de-energized or to identify the scope of the electrostatic field emanating from the source.
AC detectors can detect unshielded AC through snow, ice, and many solid objects. These battery-operated devices are handheld wands similar in size and shape to a police officer's baton.
In the presence of an AC electrostatic field, they emit an intermittent beep; the more rapid the beep, the closer the source is. The distance from the source at which the wand detects the current varies with the strength of the AC source as well as weather conditions — high relative-humidity levels can help increase the size of the electrostatic field. In general, the higher the voltage, the greater the ranges will be.
All departments should use the lessons learned and recommendations in NIOSH fatality reports to improve their individual SOGs or SOPs. When we don't fully use that information to our maximum advantage we are also taking for granted the expenditure of resources by NIOSH necessary to conduct those investigations and create the comprehensive reports.
We do a great disservice to our brother and sister firefighters when we do not take every action possible to learn from their sacrifice and take meaningful steps to ensure that a similar tragedy does not happen to our people.
Let us make a commitment today that the incident in Campbellsville involving an aerial device and energized powerlines will be the last of its kind. Our brother firefighters in Campbellsville deserve nothing less.