LOS ANGELES Broadcasters may become more enthusiastic about complying with radiofrequency radiation exposure limits now that it appears the RFR safety issue is moving up on the FCC’s enforcement priority list.
The commission’s Notice of Apparent Liability for Forfeiture against four licensees for RFR violations at the Mt. Wilson antenna farm near Los Angeles could lead to other high-profile inspections, particularly at mountaintop multi-use sites, observers believe.
The commission leveled $10,000 forfeitures against each of the stations for violating the maximum permissible exposure limits of radiofrequency radiation at a multi-user site. While the power density level produced by each individual licensee was within acceptable limits, the cumulative effect exceeded the limits, and that’s why the stations were fined, the commission stated in the related notice.
Fined were FM stations KBIG, KKBT and KRTH as well as television station KWHY. The licensees are Clear Channel, Radio One, Infinity and Telemundo, respectively. Final action on the proposed forfeitures is pending.
The investigation and subsequent fines were the result of an FCC surprise inspection at the Mt. Wilson telecommunications and antenna farm site in July of 2002.
According to the commission’s report, “FCC agents were able to access the site without encountering protective fencing or warning signs on three sides of the area.”
Many broadcast engineers consider Mt. Wilson one of the busiest and largest antenna farm in the nation. Located approximately 25 miles northeast of downtown Los Angeles in the San Gabriel Mountains, Mt. Wilson is home to 25 FM and 20 television transmission facilities. Most L.A.-area FM and TV station transmission facilities are there.
Several engineering consultants contacted by Radio World said that having an accurate RFR field study, especially in cases of multi-use facilities, should now be a top priority for broadcasters.
“Clearly, the FCC is now enforcing its rule that holds all stations jointly responsible for achieving compliance with its RFR limits,” said Bob Weller, senior engineer with consulting engineering firm Hammett and Edison.
“The FCC’s field staff have visited a number of high-profile, multi-use sites the past two years. Those with obvious RFR problems could now be targeted for formal follow-up inspections.”
Weller said any station that creates 5 percent or more of the maximum power density permitted at a given location is regarded by the FCC as a significant contributor to the problem and is eligible for a citation if the aggregate power exceeds the proscribed limit.
The FCC’s NAL in the Mt. Wilson RFR incident states, “All licensees found producing power density levels significantly greater than 5 percent of the FCC’s public limits for its particular transmitter share responsibility to ensure compliance to limits. Specifically in this case, KBIG contributed 81.75 percent, KKBT produced 11 percent, KRTH produced 11.75 percent and KWHY(TV) contributed 10.5 percent.”
The FCC declined to comment for this story. A spokeswoman said the commission was still waiting for responses from the licensees and had not moved toward any final action.
Licensees filed for an extension until mid-December to make their replies to the commission. Weller said they have three options: accept the liability and pay the fine; ask for a reduction in the fine due to extenuating circumstances or inability to pay; or show they did not violate the rules and ask for the dismissal of the NAL.
The FCC will consider the replies and then either issue a Notice of Forfeiture, which reaffirms the fine, ask for additional information or dismiss the penalties, Weller said.
“With the timeline being uncertain due to the holidays, I would not expect a final decision until early next year,” said Weller, a former commission field engineer and member of the RF Exposure subcommittee for the International Committee on Electromagnetic Safety.
The radio broadcasters involved in the RFR incident failed to return messages seeking comment for this story.
Most observers think the Mt. Wilson RFR exposure episode is far from an isolated case.
James Hatfield, partner in the consulting engineering firm Hatfield and Dawson, said, “We are aware of numerous mountaintop sites in the western U.S. where RFR levels are relatively high. It would seem prudent that licensees monitor these sites and have the areas restudied if changes have been made.”
The digital TV conversion has yielded additional concerns and problems for multi-use sites, said Robert Reymont, president of Double R. Consulting, an engineering services provider.
“I travel the country and see many multi-use sites and observe similar operations and crowding,” said Reymont. “This is a wake-up call for broadcasters to take RFR compliance more seriously.”
Reymont, who also is technical committee chairman for South Mountain near Phoenix, home to nearly 50 TV and FM radio stations and translators, said, “In light of the citations issued for Mt. Wilson, we are addressing our site RF plan revisions.”
The FCC invoked more restrictive radiofrequency radiation maximum permissible exposure limits in 1997 and established a deadline of Sept. 1, 2000, for broadcaster compliance.
The maximum RFR exposure standard for the general public is 0.2 milliwatts per square centimeter in the frequency range of 30 to 300 MHz. The occupational exposure rate is five times greater than the public exposure limit.
The FCC is considering even further modifications to its RFR guidelines. A Notice of Proposed Rule Making (ET Docket 03-137) was issued earlier this year that could change the commission’s rules for routine evaluation of compliance with exposure guidelines. Comments were due by Dec. 8.
RFR maximum permissible exposure limit violations have been few to this point. NALs were issued in 2002for KWNZ(FM) in Carson City, Nev., and KTMN(FM) in Cloudcroft, N.M., for $10,000 and $28,000 respectively. Yet the commission has determined that an appropriate base penalty amount for violation of the RFR MPE limits is $10,000, noting the public safety nature of the rules.
Cooperation at multi-use sites is key
Broadcast engineers familiar with the Mt. Wilson site believe a lack of cooperation between broadcasters in 2002 during the installation of a new antenna for KDOC(TV) resulted in the FCC’s inspection at Mt. Wilson.
One Los Angeles-based broadcast engineer said cooperation among broadcasters on Mt. Wilson has increased since the initial FCC inspection.
“Requests from stations to reduce power are now being honored. There is no longer an element of pleading or threatening,” the source said.
He said additional safety measures have been added to the Mt. Wilson transmission complex.
“There are more RF warning signs and fewer shortcuts from building to building because of additional fencing now, though the area is still not entirely fenced.”
One of the unique features of the Mt. Wilson antenna farm is its proximity to public areas, Weller said. The entrance to Mt. Wilson Observatory and Park is approximately 350 yards from one of the “hot spots” from 2002, and a post office is within 100 feet.
Despite stepped-up security at Mt. Wilson, this September a commission inspector found an open gate that leads to one of the sites entrances. As a result, the commission asked the licensees to submit their plans to ensure fences surrounding the antennas are shut and gates secured with their responses to the NAL.