Question: My boat is equipped with a nice retractable boarding ladder that is fitted into a cavity in the transom of my boat. The problem is that my children have trouble pulling the ladder out of the stowed position so that they can use it when they are swimming around the boat.
Answer: Great question! The answer is yes, there are standards that dictate boarding ladder safety requirements, in particular that the swim ladder should be deployable from the water. In the USA the ABYC Standard H-41 addresses this issue, and in UK and Europe a means of re-boarding is part of the EU's Recreational Craft Directive, which applies to boats built since 1996.
The problem in my view, though, is that the standard really doesn’t address the issue of what size person should be able to deploy the ladder. The US standard reads this way: “Means of unassisted reboarding shall be provided on all boats. The reboarding means shall be accessible to, and deployable by the person in the water.”
A child, or someone who is frail, might not have the strength necessary to actually perform this task, depending upon the design of the ladder arrangement. So, in many cases, and I suspect yours is a good example, the ladder should be deployed before the kids - or anyone else - jumps overboard.
Incidently, please make sure you aren’t letting anyone jump in the water around your boat while berthed in a marina and plugged into shore power, especially if your boat is in a freshwater marina. While anecdotally more common in north America than on this side of the Atlantic, shore power electrical leakage into the water at and around marinas is all too common and can be the cause of electric-shock drowning.