As is often the case, designers of these things don’t take into consideration sensitive matters like this.
However, I feel, to some extent, that users of the traditional toilets are at least partly to blame for the changeover to the automatic ones. I have frequently encountered UNflushed toilets in public restrooms, where someone was either in too much of a hurry to get out of there, or just too lazy to flush the darned thing so as not to gross out the next person who has to use it. There is nothing more unpleasant than to enter a stall and find that the previous user didn’t have enough consideration for others to flush their own waste. How much effort does that take, anyway? Even a kid can do it.
Another reason for installing toilets that flush automatically while one is still using them is to prevent clogging. If little bits are flushed as one goes along, it’s less likely the plumbing will get stopped up.
That said, the best way I can think of to reassure your kids that the commode isn’t gong to swallow them is to take them in with you when you go, and have them watch as the toilet does its thing while you’re on it, and see that it’s perfectly safe. Once they see it isn’t going to hurt you, they’ll probably feel more at ease when they use it. If it’s still a concern, then you can remain int he stall while it’s their turn, so they have the assurance that should anything happen, you’re right there. Once they find out nothing bad happens to either you or them, the problem might be solved.
As for the noise, just remind them that traditional toilets also make that sound when manually flushed, and this is really no different.
The only remaining shocker would be when the pressure is so strong that they get wet when the thing flushes. Not sure how to handle that one, except to lodge a complaint with whoever is in charge and see if they can get the pressures lowered. Good luck with that one – to even get somebody to listen.
While we’re on the topic of hostile commodes, one of my pet peeves are loose toilet seats that pinch when one turns on them to wipe oneself. It’s not that much trouble for maintenance people to tighten down the dang bolts so the seat stays secure. I’m sure if it was THEIR hind ends getting pinched, the problem would be remedied in a hurry! I have complained to management of several stores I’ve been in about this very problem, and have found that it goes in one ear and out the other. Next time I’m in their restroom – guess what – SAME THING. Nobody seems to give a hoot.
I won’t even start in on stalls that are so tiny that anyone of any size can barely move in them. That’s another insult, entirely.
And then there are the door locks that don’t work – or the total absence of locks! PRIVACY, ANYONE?
Hope some of these suggestions help.