Waterproof Watch with repeatable countdown timer?

[k_squared]

Part of my job as a lifeguard is dispatching guests at water slides at a busy amusement park.

Believe it or not, these people paid quite a bit to get in, and I actually care about them, so I would like to fire them off at the maximum rate possible. Sadly, I am responsible for timing this - I will create a real possibility for injury if I launch them too close together...

Does anyone know of a waterproof watch that will let me countdown repeatedly at the touch of a button? I know the safe interval designed into the ride, but I'd like to be able to launch them exactly when safe.

If at all possible, it won't beep too much, or it'll look like I'm just messing with my watch!

Thanks for any help here...

 

[lisab]

..."dispatch guests"...

Have you asked your employer for suggestions? Seems like this is more their problem than yours.

Would a lap swimming clock help?

 

[256bits]

... and I actually care about them, so I would like to fire them off at the maximum rate possible. ... a real possibility for injury if I launch them too close together...

... I know the safe interval designed into the ride, but I'd like to be able to launch them exactly when safe.

Safest interval is when the previous rider has exited the slide, and the exit area is clear. Anything other, and there is a possibility of injury due to one person colliding with another.

 

[russ_watters]

Most digital watches I've ever had have repeatable (automatic or manual reset/start) timers. Not sure about adjusting the alarm though.

 

[AlephZero]

Believe it or not, these people paid quite a bit to get in, and I actually care about them, so I would like to fire them off at the maximum rate possible. Sadly, I am responsible for timing this - I will create a real possibility for injury if I launch them too close together...

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