Redundancy remains a key priority of mass notification system design. The objective is to provide immediate and automatic system backup necessary to achieve maximum levels of failsafe operation and monitoring. Decentralizing control of the system produces higher levels of redundancy as well as enhances intelligibility and ease of use.
Integrating disparate mass notification systems effectively automates hazardous monitoring and warning functions, thereby assuring failsafe operation and accelerated response times.
While IP-based interoperable technology has had a powerful impact on emergency mass notification and continues to show substantial promise for the future, it does have possible limitations that should be considered. These deficiencies become evident in any discussion of the need for redundant system backup and monitoring, particularly as it relates to integration with more-traditional emergency warning systems and devices.
As recently illustrated by public safety emergencies like on campus shootings and natural disasters, there remains a possibility infrastructure for local telecommunications and Internet access could become overtaxed during a catastrophic incident. At a chemical processing facility, either this or a similar deficiency could seriously impair the ability to initiate both conventional and automated telephone, text messaging, paging and e-mail notification of employees as well as local officials and the general public. A fully integrated system that offers reliable backup of additional alert systems, i.e., sirens, horns, loudspeakers, signal beacons and warning lights, ensures redundancy is built in at all levels of emergency mass notification.
Interoperable communications is playing an increasingly important role in emergency mass notification. However, reliance on telecommunications and Internet infrastructures that recently have proven inadequate emphasize the need for automated backup by more traditional warning systems such as sirens and signaling beacons.
Keep it Simple
This is the formula for success in emergency mass notification. Complex warning alerts and messages or an excess number of scenarios and action plans could well add to confusion of an emergency situation.
In laying out a strategic emergency plan, limiting the number and simplifying the complexity of warnings and alerts is critical. For example, at the world's largest liquefied natural gas production facility, a single alert tone is used for all emergency situations. Although the system can provide hundreds of different tones, relying on a single tone eliminates the need for employees to memorize, interpret and react to multiple tones and their associated meanings. Once the tone sounds it's immediately followed by more-detailed voice instruction broadcast over the public address system — but by that time the entire facility has been alerted to the need for immediate action.
In another example, an isomerization plant at a major Texas refinery employs a slightly more complex warning system — four warbler siren blasts: one for testing, two for work stoppage, three for evacuation of nonessential personnel and a continuous blast for total evacuation.
Limiting the number and complexity of emergency warning signals is an effective way to minimize confusion and assure immediate and effective response during a catastrophic incident involving hazardous chemical materials.
Considering human life may be at stake, a plant must strive to base it's emergency mass notification strategy on best practices. So, let's look at how these are evolving.