This Operations Standard/Model Recommendation is published by the National Emergency Number Association (NENA) as an information source for the voluntary use of communication centers and is provided as an example only. It is not intended to be a complete operational directive. NENA reserves the right to revise this for any reason including, but not limited to, conformity with criteria or standards promulgated by various regulatory agencies, utilization of advances in the state of operational techniques or services described herein. It is possible that certain federal, state or local regulations may restrict or require modification of the recommendations contained in this document. Therefore, this document should not be the only source of information used. NENA members are advised to contact their legal counsel to ensure compatibility with local requirements. By using this document, the user agrees that NENA will have no liability for any consequential, incidental, special, or punitive damages arising from use of the document. NENA’s Operations Committee has developed this document. Recommendations for changes to this document may be submitted via email to firstname.lastname@example.org or via mail to
To submit an update or takedown request for this paper, please submit an Update/Correction/Removal Request.