Hi there , i have a question about the sleeping mattress, I know that inflatable mattress are not allowed but what about the self inflatable mattress which have polyurethane in it and once you open air cap the mattress swelled a little bit by itself and you dont need any pump or other device to inflate .it also only swelled to 6cm or 2.35 inch . Can we use it for kids sleeping. https://amzn.asia/d/iE44UU0 Thanks in advance ! Dan