Wash. Rev. Code § 80.36.560
By January 1, 1997, or one year after enhanced 911 service becomes available or a private switch automatic location identification service approved by the Washington utilities and transportation commission is available from the serving local exchange telecommunications company, whichever is later, any commercial shared services provider of private shared telecommunications services for hire or resale to the general public to multiple unaffiliated business users from a single system shall assure that such a system is connected to the public switched network such that calls to 911 result in automatic location identification for each telephone in a format that is compatible with the existing or planned county enhanced 911 system. This section shall apply only to providers of service to businesses containing a physical area exceeding twenty-five thousand square feet, or businesses on more than one floor of a building, or businesses in multiple buildings.
RCW 80.36.560
Findings-Severability-1995 c 243: See notes following RCW 80.36.555.