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New Program Evaluates Labs for Emergency Communications Tests

To help ensure that first responders, public safety officers and military personnel can always talk with each other no matter what communications equipment they are using (a characteristic known as interoperability), the National Institute of Standards and Technology (NIST) and the Department of Homeland Security (DHS) have teamed up to create the Project 25 Conformity Assessment Program (P25 CAP).

The latest milestone of the recently launched program is the publication of the 2009 edition of NIST Handbook 153, Laboratory Recognition Process for Project 25 Compliance Assessment. The guide details the procedures by which independent testing laboratories can be evaluated for their ability to determine how well public safety and emergency communications devices meet the performance standard for interoperability known as Project 25 (P25).

NIST Handbook 153 – Laboratory Recognition Process for Project 25 – Compliance Assessment, January 2009 may be downloaded from the OLES documents Web site at….

Initially, P25 CAP focuses on the most mature of the nine interoperability standards that will eventually make up the P25 suite—the Common Air Interface (CAI). The CAI is the standard that describes the physical and logistical characteristics of a link between the two stations that make up a radio communication system—the base and mobile handsets. A radio using P25 CAI should be able to communicate with any other P25 CAI radio, regardless of what manufacturers produced the two units.

As other interfaces become better defined, they will be added to the testing lab assessment criteria.

NIST's Office of Law Enforcement Standards (OLES) designed the P25 CAP protocols that are being used by DHS's Office of Interoperability and Compatability (OIC) to recognize independent laboratories across the country capable of offering interoperability testing of equipment to manufacturers and users.

The P25 suite of interoperability standards is being developed by representatives from local, state and federal public safety associations and agencies. It is administered by the Telecommunications Industry Association.

Laboratories wishing to be reviewed for their P25 testing ability should contact Dereck Orr, dereck.orr [at] (dereck[dot]orr[at]nist[dot]gov), (303) 497-5400. For more information on the P25 CAP, contact Orr or Luke Berndt, DHS, at luke.berndt [at] (luke[dot]berndt[at]dhs[dot]gov), (202) 254-5332.

Released March 24, 2009, Updated January 12, 2023