Public Safety DAS Maintenance

Service Description

Public Safety DAS is installed to enable first responders within the building to communicate with each other and their base during an emergency. It is NOT to be confused with a commercial DAS system which provides signal from commercial carriers, such AT&T & T-Mobile. Public Safety DAS or (ERRCS) must be on a different spectrum from commercial wireless and covers the entire building, including basements and stairwells – areas where having commercial wireless signal is NOT critical. Public safety DAS must also have backup power in case of an outage. Critical Areas, such as a fire command center, fire pump room, exit stairs, exit passageways, elevator lobbies, standpipe cabinets, sprinkler sectional valve locations, and other areas deemed critical by the authority having jurisdiction are required to provide 99 percent floor area radio coverage for specific frequencies the first reponders in that jurisdiction use. While most cities have adopted this mandate and require a DAS system for first responders’ use, specifications for what is required vary from city to city. The most important variation is in frequencies to be included in a system since not all cities’ Fire and Police departments use the same frequencies. These variations also apply to codes adopted and applied to required infrastructure for the DAS or ERRCS provisions; for example, whether or not wiring pathway should be in conduit or whether or not it needs to be enclosed within a 2-hour rated assembly. Variations also exist in how often a given AHJ (assigned electrical and fire inspectors) enforce city adopted guidelines/codes in their review of the infrastructure. As a result, the AHJ for the project address is the best source of information for what specific guidelines are attached to a DAS system to be provided for the project. Even when all requirements for a Public Safety system are set and documented by the city, the interpretations of the AHJ inspectors assigned to the project ultimately decide what is specifically required.