Emergency Ambulance Services Access Assurance Act of 1999

Emergency Ambulance Services Access Assurance Act of 1999 - Amends the Public Health Service Act and the Employee Retirement Income Security Act of 1974 (ERISA) to require a group health plan, or coverage offered in connection with a health insurance issuer, if it provides emergency services coverage, to cover emergency services (and, if it provides coverage for emergency ambulance services, to cover emergency ambulance services): (1) without a prior authorization requirement; (2) whether or not the provider is a participating provider; (3) in a manner so that, if the services are provided by a nonparticipating provider without prior authorization, the participant, beneficiary, or enrollee is not liable for amounts exceeding the amount that would be incurred with a participating provider with authorization; and (4) without regard to most other conditions of coverage. Defines "emergency medical condition" by a prudent layperson standard. Amends the Internal Revenue Code to apply the same requirements and standard to a group health plan. Amends the Public Health Service Act to apply the same requirements to an issuer in the individual market.