The NSA also conducts five-year periodic reinvestigation polygraphs of employees, focusing on counterintelligence programs. Other sections concentrate on profiling, special interrogation techniques and polygraphs. Applicants who fail polygraphs may not gain employment with the FBI. Former CIA agent Robert Baer described the frequency of the polygraphs as rare. He altered recruiting and hiring to incorporate background checks and polygraphs. The agency polygraphs about 10,000 applicants annually. He refused to allow polygraphs, and ended the investigation. Hawkins & Peale lost money producing polygraphs. In the late 1980s Ivanova studied at the Bulgarian National College of Polygraphs and Photography. Voltaire and Diderot are examples of modern polygraphs. Lewis's children have volunteered to take polygraphs. They were introduced as "polygraphs" by Albert Burroni and as "computads" by Ross Street. She arranges for polygraphs for all those who had access to the prisoner. In the province of Ontario, the use of polygraphs is not permitted by an employer. The police wanted to give polygraphs to two members of Burchett's staff.