Here in the states, I have heard 2 months for record retention for paper pre-shifts and I was told once 4 years! I found out later the 4 years was based on a miss-applied ANSI standard written for aerial lift equipment record retention. All the time frames I've heard over the years given by an OSHA office is not based on any applicable law or standard, just a local recommendation. Listening to your local OSHA office recommendation makes a lot of sense. Those are the individuals you will hope to satify in an accident investigation if something happens. I agree with the previous posts saying written or documented pre-shift inspections are not required by the CFR 1910.178. But, OSHA in accident investigations have asked operators if they do pre-shift inspections and what items they inspect. OSHA officers have asked for training information used for training operators and then look for pre-shift inspections to be covered in training. I have heard and read about OSHA officers being satisfied by electronic pre-shift inspections like we see offered by Shockwatch or pre-shift inspection points lists posted on the machine (not dated, just a decal) or maybe a pre-shift list posted on a wall in a battery charging station to help an operator to not forget an item. An employer must have something to point to that supports pre-shift inspections are important, part of their culture, and are being done when OSHA gets involved. A dated, daily, or every shift piece of paper is not required by law. As pointed out in previous posts, dated documentation can have tremendous value in civil cases. Unfortunately in the states, we do not benefit from "loser pays" and every election tort reform never seems to be a real campaign issue. So, just about anything can happen in a civil case. The more documentation you have the better. But, when you do dated daily documentation you have to be perfect. You can't have missed days or missed shifts if the machine was in use. If you have missing records you might have been better off to have no dated records at all! Missing dates or shifts is now documentation that you are not doing pre-shift inspections. The most important thing is that pre-shifts are done. It is foolish to get on a 9000lbs machine, start the engine, release the park brake, throw it in gear, and stomp the accelerator getting the machine up to top speed. That is absolutely a foolish thing to do! Why? Did I say the operator made sure the brake pedal didn't go to floor before putting it in gear? Everybody wins when good pre-shift inspections are completed. Pre-shift inspections should be about common sense first and the question of documentation or not... last. If the employer decides to document, check with your local OSHA office and get their recommendation for suggested record retention.