E-Field detection keeps jobsites safe
By Lance Burney13 May 2019
When it comes to jobsite safety, high standards must be in place.
Proximity alarms and the science of E-Field detection have evolved to the point that cranes, fire trucks, ambulances, military vehicles and other heavy equipment can be made safer. The goal is always to alert the operator of the proximity to danger in enough time for him or her to move away from overhead power lines and prevent contact.
The science of E-Field detection allows proximity alarms to warn crane operators and ground personnel of danger.
Stopping crane-related injuries means staying abreast of the latest research. A leader in construction accident research, Dr. Jim Wiethorn is the principal engineer and chairman of Haag Engineering’s Crane Group, a failure and damage consulting firm based in Houston. Wiethorn has spent many years deconstructing incidents involving cranes to determine what happened and why.
According to Wiethorn’s research, more injuries occur when people are not involved in actual lifting operations than when they are. Moreover, a serious lack of communication often exists between crews and crane service providers. Dr. Wiethorn believes that bridging this gap is essential for preventing accidents. He also stresses the importance of OSHA requiring mandatory crane operator certification. Certified operators are essential to keeping workers safe on the job.
Crane accidents can be prevented if multiple layers of protection are used. Dr. Wiethorn stressed the importance of paying attention to mixing crews who have not worked together and addressing how things are done at the jobsite. Safety talks focusing on the protection available must be given prior to beginning any project. Finally, miscommunications should be addressed before work begins so there are no misunderstandings.
Recognizing that jobsite communication is essential, high voltage proximity alarms warn workers and bystanders of potential power line contact. These alarms work by alerting users when the device detects a certain voltage. An audio or visual alarm will sound, letting the crane operator know to take action. When correctly installed, these alarms let crane operators know where it is and isn’t safe to operate and stop accidents before they start.
The application of scientific knowledge has enabled Sigalarm to greatly improve jobsite safety conditions. One particular scientific advancement has been of utmost importance and that is the understanding of E-Field strength.
E-Fields are highly studied, measurable and documented by science. Electric field is defined as the electric force per unit charge. The direction of the field is taken to be the direction of the force it would exert on a positive test charge. These fields are invisible, however are detectable by proximity alarms. Simple adjustment of coarse and fine controls on the Sigalarm permit accurate and repeatable warnings.
Using wireless technology, proximity alarms can detect the E-Field present and provide a warning. To that end, companies need to make sure they are trained in using these alarms so operators can prevent injuries. Also, jobsites need to have evident boundaries that define work areas. By having the work area clearly marked, crane operators will know where it is and is not safe to go.
Cranes and power line video
Does your company operate cranes near or around power lines? Are your workers trained to the current OSHA standard (29 CFR Part 1926) for these operations? SC&RA has developed a 20-minute video and accompanying booklet that could help save lives. The video covers:
- Planning the assembly or disassembly of a crane near a power line
- Encroachment prevention measures
- When to use a spotter and alternative measures to spotters
- When operations can take place under a power line
- Working near transmitter towers
“The video and booklet are designed to be used as the curriculum for a training course and in planning meetings prior to bringing a crane onto a worksite,” said Beth O’Quinn, senior vice president, SC&RA. “The products show real world examples of conditions and situations crane operators, signal persons, riggers and construction workers encounter every day while operating near and around power lines.”
For information please visit www.scranet.org/powerlinesdvd