N.J. Stat. § 34:19-4
The protection against retaliatory action provided by this act pertaining to disclosure to a public body shall not apply to an employee who makes a disclosure to a public body unless the employee has brought the activity, policy or practice in violation of a law, or a rule or regulation promulgated pursuant to law to the attention of a supervisor of the employee by written notice and has afforded the employer a reasonable opportunity to correct the activity, policy or practice. Disclosure shall not be required where the employee is reasonably certain that the activity, policy or practice is known to one or more supervisors of the employer or where the employee reasonably fears physical harm as a result of the disclosure provided, however, that the situation is emergency in nature.
N.J.S. § 34:19-4