I would do the refresher on both. I would also do a scaled down version of the initial written tests on each truck. Also, I would have them replicate their day-to-day duties on both trucks as well, during the practical. They have been driving for some time now and have not killed themselves yet so I would not bother spending an entire day refreshing. According to our old CSA guidlines in Canada, 8 hours was the supposed norm for initial theory, but only 4 hours on the refresher.
Now, I am assuming that these refreshers are first-time 'refreshers' after the initial training. I would spend the morning on both machines, battery, break for lunch, propane if required, write scaled down tests, and then watch them drive. 6 hours at the max, even as little as 5 hours, but not a full 8 hours. remember, you have taught this stuff to them previously, and now you are just topping up, or reminding them on certain items that they may have forgotten, or they have become complacent.
The crunch comes when they are 3rd time refreshers, and they know what to do, and have not gotten into any incidents, and are very good at what they do. Now, what can you teach them, that doesn't sound like a broken record, and maintain their interests at the same time.
Danny
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