Safety and Health Audit Promotion and Whistleblower Improvement Act of 1999

Safety and Health Audit Promotion and Whistleblower Improvement Act of 1999 - Amends the Occupational Safety and Health Act of 1970 to revise provisions relating to audit reports and discrimination prohibitions.

(Sec. 2) Exempts safety and health assessments, audits, and reviews conducted by or for an employer from disclosure in enforcement actions, with specified exceptions.

Authorizes requiring disclosure of such records, reports, or other information to the extent they are sought: (1) as part of a criminal proceeding; or (2) to establish the cause of a particular alleged violation, but only if certain conditions are met. Makes such disclosed information admissible as evidence in any civil or administrative proceeding only to the extent that the Secretary of Labor establishes that the employer has not acted in good faith with respect to the audit for which such information was prepared or obtained.

(Sec. 3) Prohibits employer reprisals against employees based on certain employee conduct concerning safe and healthy working conditions.