2010-05-01 Soda bottle bombs

An open letter to our local CERT coordinator/instructor, who recently sent around a warning about soda bottle bombs that, among other things, referenced http://www.snopes.com/crime/warnings/bottlebomb.asp .

Hi, Bill,

This is going just to you, but feel free to send it back out to the group if you deem it appropriate.

I've got a solution to such things: Help kids, either your own, neighborhood, or otherwise by proxy, build and detonate such devices safely!

Childhood these days can be mind-numbingly boring, and the temptation to sneak around and build something like this that they've seen on the internet is overwhelming. The two incidents I'm aware of in Sonoma County seem like they were a case of a bunch of kids playing around with chemistry (in my opinion, something we should encourage, we need more kids interested in science!) who got interrupted by an adult and scattered, leaving a situation that would have been entirely manageable had the kids not been scared of discovery, or had the adults had a clue about what was going on.

Soda bottles bombs are, for all noise they make, and the potential damage they can cause, amazingly safe. When they explode the shrapnel slows very quickly, so if you're more than a few feet away from them you just feel the air shockwave, and if made with benign ingredients like dry ice (or just pumped air) there's no environmentally hazardous residue, and the loud "bang" is amazingly satisfying.

So kids are going to make them.

But if you end up with a situation where people are handling live ones directly then, yeah, there's a good chance people are going to end up with cuts or broken wrists.

I have a little bit of experience with them. Here's a video of me and a 15 year old (at the time) nephew blowing up a trash can with a soda bottle bomb created by drilling a hole in the cap, cutting a tire valve to fit in the cap, and pumping the whole thing up to 120PSI. Note that the effects of this explosion are muffled because we'd already blown up the trash can once, and had taped it back together and lined it with a trash bag:


We were doing the explosions in water because we didn't want to alarm our neighbors, because the first time we didn't and... well... it was really loud.

Since kids are going to make these things anyway, we can help them to both stay safe and keep us safe, by suggesting that they use controlled systems (ie: pumped air and mechanical detonation rather than chemical reactions, cap it up and pray it explodes and you don't have a live ordinance on your hands), by offering reasonable safety measures (eye protection, and hearing protection where appropriate), and by working up to the bigger stuff incrementally, so that they discover their limits before they, or someone else, lose a limb.

For instance:

This same nephew brought a couple of his friends over with the desire to make a bunch of ammonium tri-iodide, an extremely unstable high explosive (makes nitroglycerin look tame). I suggested we start with a pea-sized amount of it, so we did, and after it exploded semi-unexpectedly, doing little more than turning the coffee filter we were drying the substance on into a doily, they resisted my suggestions that we should make a bigger batch. Had they gone off and done it without adult supervision, you can bet that they'd have started with their original plans, been nervous about discovery, and there'd be all sorts of reasons for us to be nervous.

And there are lots of instructive and safe experiments we can do to both encourage kids to be inquisitive and want to learn on their own, and break up the monotony and boredom of a modern childhood. For instance, here's the explosion of a balloon filled with hydrogen, generated with pennies and common cleaning supplies, set off by two third graders from across the street (didn't include him in the video because I like to make sure there's consent for any public images):


So rather than spreading the fear, the "oh my, kids these days are doing dangerous things", I think we need to be saying "yeah, and if we take that creativity and funnel it in safe and exciting ways we can get them the heck away from the television and out into the real world, where they'll make our future *amazing*!"

And it's going to be those sorts of kids, the resourceful ones who understand physics and chemistry and how to jury rig stuff safely, who are the ones we're going to be wanting at our sides in a disaster situation.


Category: Dan Lyke life