Most nationwide polygraph organizations do NO 'certifying'; they leave that up to 'local' polygraph groups.
Most local polygraph groups will 'allow' their PAID members to say that they are 'certified' for that year if they say they had a minimum of 12 hours of education that year-- and if they PAY THEM A FEE! Most members, receiving no credible education during that year, instead choose to attend that group's yearly social get-together: which (for a fee!) just happens to 'also' satisfy their minimum education hours to 'allow' them to say they are 'certified'!
PEOA (www.peoa.US) requires the highest hours in the lie-detection profession-- a minimum of 15 hours per year-- for their yearly 'certified' designation. Polygraph Examiners of America, the world's largest lie-detection network, makes available to its members a choice of venues for FREE continuing education hours every year.
If you are considering the hiring of an examiner who claims to be 'certified', you might ask him/her exactly what & when recent training he/she claims was the source of their CURRENT certification-- then verify it. If it came from a group that does not have its own phone number for such verification, then, oh well.
PEOA verifies its member's certifications at 818-883-6969.