Calling from a Private Telephone System or PBX

Private telephone systems, such as PBX’s, do not interface to the Enhanced 9-1-1 system in many cases. Citizens served by these telephone systems may be denied the benefits of the Enhanced 9-1-1 system, such as the automatic location and number identification and selective routing features. When a 9-1-1 call is made from a telephone connected to a private telephone system, the location information which is displayed at the 9-1-1 center may not be correct. In some cases, the address which is displayed is the address where the telephone switch is located, not the location of the 9-1-1 caller. In addition to the incorrect display of location information, the 9-1-1 call may not be routed to the appropriate 9-1-1 communications center as a result of the incorrect address. Especially in situations where the caller is unable to communicate and give their location, responses to these 9-1-1 calls may be delayed, or not possible.

There are currently no national standards which address the incompatibility issues between private telephone systems and Enhanced 9-1-1 systems. In an effort to work towards the resolution of this issue, the Washington State Legislature passed Substitute Senate Bill 5089 in 1995, and this bill was signed into law. The bill requires private telephone system which serves citizens in settings where risks are highest to interface to the enhanced 9-1-1 system by providing a call back telephone number and correct location information. The areas which are covered by this legislation are: residences served by shared telecommunications service providers; common and public schools; and some settings where multiple unaffiliated businesses are served by a commercial shared telecommunications service provider from a single switch. In addition to this legislation, all local exchange companies offering service in the State of Washington are required to provide the capability of interfacing private telephone systems to 9-1-1. Private telephone system owners should contact their local exchange company and their switch vendor for information.

Even though only certain types of private telephone systems are currently required to interface to Enhanced 9-1-1 systems, all private telephone system owners and users should be aware of the incompatibility issue and of the potential delay in 9-1-1 response this situation creates.

Residential Customers
All shared telecommunications service providers serving customers who reside in Uniform Building Code Occupancy Group Classification R-1 must assure that their telecommunications system is connected to the public switched network such that calls to 0-1-1 result in accurate Automatic Location Identification for each residential unit.

The residential customers included in this classification are persons living in single-family or multi-family dwellings (e.g. condominiums, apartment buildings and complexes, retirement and nursing homes and dormitories). Persons detained in jails and persons who are temporarily hospitalized are not included in this classification.

The minimum information requirements for Automatic Location Identification for residential customers are:

• Customer Name
• Street Address and City
• Dwelling unit identifier (i.e. apartment number)
• Call back telephone number

Also included in this classification are residential customers in congregate residences, hotels and motels.

Common and Public Schools
All common and public schools as defined in RCW 28.A.150.010 and .020 must provide persons using school facilities direct access to telephones that are connected to the public switched network such that calls to 9-1-1 result in accurate Automatic Location Identification for each telephone during all times when the school facility is in use. Schools are not required to modify or replace their existing telephone system. This requirement could be met by installing pay phones or single-line phones in areas that are always accessible to persons using school facilities.

Multiple unaffiliated businesses
Any commercial shared telecommunication service provider of private shared telecommunications services for hire or resale to multiple unaffiliated business users from a single system must assure that the system is connected to the public switched network such that calls to 9-1-1 result in accurate Automatic location Identification for each telephone. This requirement only applies to providers of service to businesses containing a physical area exceeding 25,000 square feet, or businesses on more than one floor of a building or in multiple buildings. This requirement does not apply to a business that owns a private telephone switch which serves only their own business or affiliated businesses.

Voluntary Compliance
Other private telephone systems that are not included in the above definitions as being required to interface to Enhanced 9-1-1 systems may obtain a certification of voluntary compliance.

The minimum information requirements for Automatic Location Identification for voluntary compliance are:

• Customer Name
• Street Address and City
• Building Unit Identifier or specific location information
• Call back telephone number

Further information may be found by contacting the King County E-9-1-1 Program Office (206) 296-3911.

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