RF Exposure Utility Worker Safety and Small Cells September 23, 2016 Site Safe, Inc.
RF SAFETY Radio Frequency (RF) Safety is worker and general public safety around wireless transmitters September 23, 2016 Site Safe, Inc. 2
REGULATORY FCC AND OSHA OSHA General Duty Clause Employer shall furnish a safe workplace Employee has a right to know about hazards and shall comply with safety standards FCC - Rules, Part 1, Subpart I Exposure limits Rule 1.1310 Rules based on NCRP / ANSI / IEEE recommendations (consistent with International rules ICNIRP) Under review (2014 NOI) September 23, 2016 Site Safe, Inc. 3
EXPOSURE LIMITS FCC Exposure Limits - two levels of protection Occupational or Controlled Limits 10 time safety factor below known biological effects General Population or Uncontrolled Limits are 5 times additionally lower (total of 50 times safety factor) Occupational: personal who through training are aware of and can control their exposure Limits Based on Spatial & Time Averaging whole body exposure over time Partial Body (hands, head, etc.) exposure limits are higher September 23, 2016 Site Safe, Inc. 4
WHAT DOES IT MEAN? RF exposure at high levels can be dangerous Know where exposure exceeds limits RF Exposure Assessment (modeling / measurement) Knowing where it is safe to work will ensure safety If you have to work where exposure may or does exceed limits, take appropriate action Safety Concern - wireless sites with workers who may or must be close to antennas Relative Risk (versus High Voltage, Fall Protection, etc.) Medical Implants use the General Public limit unless approved by physician September 23, 2016 Site Safe, Inc. 5
RF AWARENESS TRAINING Training provided to make someone qualified to work in areas that exceed the General Public exposure limits. The goal of training is to allow a worker to be aware of and control their exposure. RF Basics Regulations How to Work Safely Specific for an installation or type of installations (DAS) General for working at (most) RF installations Expanded for managers, safety officers, designers A trained worker may work in areas that exceed the General Public Limit All Day September 23, 2016 Site Safe, Inc. 6
RF ALERTING SIGNS Blue Notice Sign This sign indicates an area where exposures may exceed General Public limits. RF levels may be greater than the General Public limits but they will be less than the limits for human exposure or the Occupational limits. Work can safely be done in this area with no time restrictions or need for personal monitors or other controls. Workers should be aware of antenna locations and understand that if they must work above the walking surface near antennas, additional precautions are required. Yellow Caution Sign This sign indicates an area where RF levels may exceed Occupational or human exposure limits.! CAUTION Workers should use personal monitors to determine if exposure in their work area exceeds limits, paying close attention to areas immediately in front of antennas. Reduced power or turning off transmitters may be required to work in this area for more than a few minutes.
RF ALERTING SIGNS Orange Warning Sign This sign is used to indicate areas which greatly exceed Occupational or human exposure limits and immediate harm may result. Typically, these signs are placed on broadcast or other high power installations. Working in areas with orange Warning signs must include coordination with the antenna owner, the power should either be reduced or turned off, and monitoring or lock-out-tag-out procedures must be employed. September 23, 2016 Site Safe, Inc. 8
RF MONITORS Only useful in combination with RF Awareness training Used to determine personal exposure right now Review manufactures specs is it right for your environment? some have limited frequency Ascertain if antennas that you are working near are active or not September 23, 2016 Site Safe, Inc. 9
UTILITY POLES Antennas at tops of poles have little exposure risk Different types of installations will have different distances to exposure limit perimeter Below the antennas, exposure levels are generally well below limits Disconnects can ensure no RF exposure September 23, 2016 Site Safe, Inc. 10
TRANSMISSION TOWERS Antennas at tops of poles have little exposure risk Climb or lift through - caution September 23, 2016 Site Safe, Inc. 11
OTHER SITES Behind antennas little exposure Microwave Dishes very little exposure Omni Antennas Land Mobile can cause levels to exceed limits (but are usually intermittent) Caution using lifts in front of antennas September 23, 2016 Site Safe, Inc. 12
MICROWAVES Microwave Dishes / Panels have high gain and typically little transmitter power For most there is no area that exceeds limits Follow signs Don t stand in front it will block the signal and make the microwave link fail! September 23, 2016 Site Safe, Inc. 13
SAFETY PRACTICE IN ACTION If workplace exceeds Occupational limits: shutdown antenna and verify with RF monitor (if no disconnect / lockout / tagout) Trained worker can be in area that does not exceed Occupational limits Trained workers may pass through area that does time averaging September 23, 2016 Site Safe, Inc. 14
QUESTIONS Matt Butcher, PE VP Engineering Site Safe, Inc. 200 North Glebe Road, Suite 1000 Arlington, VA 22203 U.S.A. Office: (703) 558-0502 Mobile: (703) 598-5490 Email: matt@sitesafe.com Website: www.sitesafe.com September 23, 2016 Site Safe, Inc. 15