What are the exceptions under EPPA to allow polygraph testing?

The exceptions under the EPPA allow polygraph testing under the following circumstances:?
Private employees who are working as consultants to, or are employees of firms that are contractors to federal national security intelligence operations;
Employers engaged in the provision of private security services, armored car services, or the installation and maintenance of security alarm systems may require polygraph testing of certain prospective employees;
Employers whose business involves the manufacture, sale, or distribution of controlled substances (drugs) are authorized to test employees who have direct access to the controlled substances; and
Employers who have a reasonable basis to suspect that employees may have been involved in an incident that resulted in economic loss to the employer may request that those employees take polygraph tests.