Hi Charlie,
If memory serves me correctly, When we first designed the wood restoration course, This art of cleaning and sealing wood was very knew to the industry. Chemicals and techniques were just being discoverd and changing at a rapid rate. We didn't know that it would take off as well as it has. Because I was the guy who did the course originally I personally felt that 3 years was a good idea to keep guy's n girls abreast of the changes.
I personally think anywhere from 3 to 5 years is acceptable, The big plus to have people return every 3 years for recertification is that they get to come to another PWNA convention. They always learn something new and meet knew friends. Plus the revenue generated by the schools helps the organization financially.
I'm certainly not opposed to increasing the certification time, but would hate to decrease the dollars coming into the org.
If the wood certified people (members) as a whole feel this certification should be extended, we could certainly put it to a vote, then of course we would have to do what ever the members vote on.
Charlie, thanks for asking...
Chris Detter