Emergency window latches and such

[Taz420]

So this is about my party bus. It is a 2003 Turtle Top TerraTransit 24 passenger, and since it is a commercial vehicle, the emergency windows are required (non-negotiable). However the latches on all four windows work themselves loose over the course of a ride (I open and reset them before every ride during pre-trip), and I am starting to get nervous that one could pop open - especially if someone puts weight on it. Every once in a while I have to yell at someone about opening the back door or the roof hatch too, so it would not be unfathomable that someone would open one purposely either (drunk people have the attention span of your average puppy). I seriously do not want to end up on the news for someone falling out of my bus, but safety requirements limit what I can do as far as making things hard to open.

I definitely need to replace the latches, and I thought of using the ones that have alarm switches (and building a little LED panel with a buzzer that shows any that are unlocked), but I had no clue there were so many different kinds. I have found some designs that have switches as an option but not all. I didn't think to snap a picture, I can do that tomorrow if it'll help, but they are the curved red handle that mounts to the SIDE of the movable frame - you lift it toward the front or back of the bus, and have a curved "blade" that engages the mounted frame. I haven't really looked further yet but how do I know which design/style or manufacturer I need? Many look similar but are obviously different (size, mounting holes, etc).

The back door has a jamb switch for the alarm, but I'm going to install a plunger switch on the vertical latch that'll tell me if it's not completely locked (since the jamb switch only tells me if the door is actually open, not if it's unlocked).. But maybe anyone more versed in regs could help here.. Is there anything on the books that dictates like, "maximum force" required to open an emergency exit? I was thinking I could put like a bungee or something on the latch swing arm with enough tension to keep it "pulled" down, and prevent it from being bumped or moved accidentally, but still allow it to be operated. I know it can't be deadbolted (has to be able to be opened from outside, in fact deadbolts require a starter interlock and alarm) or require any type of tool including a key, but I don't want to get an ironic safety violation while trying to keep my passengers safe.