But perhaps the biggest advantage of the wireless PA system is that it enhances response times due to its “ability to make announcements through the two-way radios from a non-specific location.” Orr said.  Now, any radio-equipped personnel can access the wireless PA system to make an announcement.  Previously, personnel would have had to travel to one of the hardwired PA stations – assuming that they knew where the closest one was located – and then make the announcement.  Given the size of the facility, this travel time could be critical in an emergency situation.  Now, with the ability to make announcements from any radio, the travel time is removed—and emergency messaging can occur in real-time.  

Messaging is simple with the wireless PA system, and adherence to the local custom of employing a dual tone to announce the coming of an announcement easily was accomplished.

Other challenges solved

With portions of this plant built in the 1920’s, there are many areas which proved a challenge for locating PA speakers.  There also are portions of the plant which have been deactivated, but through which personnel routinely travel, so these are included in the “messaging footprint.” 

“I was walking through these areas to locate speakers, and it would be pitch black,” Orr said.  “Every once in a while I’d run across someone and startle them because they were not expecting to see me.”

Orr recalled some areas of the cavernous facility where the flexibility of the wireless speaker installation really came into play.  Some are large open areas; to services these, he was able to locate speakers on alternate floors and still achieve adequate coverage.  In other instances, there are rooms within rooms where speakers could be located, which allowed him to deal with some areas in a more intimate, individualized manner.

The ability of each system receiver to support two wireless PA speaker horns also was helpful in customizing areas with appropriate sound levels.  When two speaker horns installed, effective sound pressure level (SPL) is reduced by half; however, each speaker can be positioned independently, i.e., 180 degrees from each other, providing added coverage flexibility to cover more areas with a single installation point. 

Each receiver can be fine-tuned for volume as well, depending upon ambient noise and environmental conditions.  Orr originally set the volume at 90% for the 225 speakers installed to date, though those in office areas or control rooms were much lower.

“We got some complaints that the speakers were too darn loud and please come turn it down” Orr said.  “We wanted to get those complaints to see where the sensitive areas are.” 

He figures they’ve turned down the volume in four or five areas—mainly job trailers and control rooms—while those in areas like the gas-turbine facility continue to blast their messages at a high level because of the high level of ambient noise. 

Conclusion

Cardinal Wireless was awarded the project in November 2012 and the deployment—which included the installation of 300 wireless PA speakers—was completed in January, 2013. 

The facility uses approximately 100 portable radios, with two or three repeaters providing four or six talk paths. The wireless PA system uses one analog repeater, which provides communication capability throughout the facility based on its strategic location.

The wireless PA system has been so successful in delivering messages that it has supplanted the hardwired system that it was originally intended to augment.  It was installed in much less time and at a fraction of the cost of a traditional hardwired PA system. 

In addition to delivering audible messaging throughout the 200-acre, multi-building facility—each receiver is fine-tuned to the ambient noise and working environment in which it is located.  This allows delivery of routine and emergency messages—in real-time—to all of the facility’s hundreds of employees, regardless of where they work. 

Finally, though the aforementioned time and cost savings are important, the ability to safeguard their employees is the most important aspect of the new system.

Steve Rice is president of Carmel, Ind.-headquartered Ritron Wireless Solutions manufacturer of the LoudMouth wireless PA system.