Is that garbage can bear resistant? These bears will find out

FLORA LICHTMAN: Before we start the show, we are working on a story about a new trend in GLP-1 medications– microdosing. And we want to hear from you. Have you tried microdosing a GLP-1 drug? Tell us about it. Why? How did you get it? What was your experience like? Call us with your story or questions about microdosing GLP-1s at 877-4-SCIFRI. That’s 877-4-SCIFRI.

IRA FLATOW: Hey, it’s Ira, and you’re listening to Science Friday. Now, here’s a question you don’t think about every day, but bear with me. Have you ever wondered what it means for something to be bear resistant? You know, that cooler you take camping or the compost bin in your backyard that promises to keep hungry bears out.

Well, wonder no more. My next guest will take you inside the workplace of the grizzly bears, whose job it is to tear apart consumer goods. You’ll also find other creative experiments to test the safety of airplanes, skyscrapers, pill bottles, and more. Alex Davies is a journalist and author of the Kobuk the Destroyer– and Other Tales from the Wild, Unseen World of Test Engineering. Alex, welcome to Science Friday.

ALEX DAVIES: Hey, Ira. Thanks for having me.

IRA FLATOW: Until I read your book, I never considered that actual bears were used to test whether there’s– something that is bear proof. I mean, where did the bears come from? How do you hire them? How do they become product testers?

ALEX DAVIES: So the bears best equipped to do this work are what we typically call problem bears, which is a euphemism for bears who are accustomed to human food and are therefore looking for human food. So the story of Kobuk the destroyer, Kobuk was a cub in the Alaskan interior, and Kobuk’s mom was a classic problem bear, where she was used to human food. And she led her cubs onto an Alaskan rancher’s land and started killing and eating his free-range chickens.

And the rancher shot and killed Kobuk’s mother and one of her cubs. But Kobuk and his sister, who became named Nikina, were rescued. And what happens with a lot of problem bears is they’re either relocated more often, or very often they’re euthanized. But Kobuk and Nikina hit the lottery.

They got transported to Montana to a grizzly bear sanctuary, where their job is just to live happily, be there. But also they have to sing for their supper, so to speak. And these are bears that are used to test supposedly bear-resistant products. It’s important we don’t use the term bear proof because you can’t prove something is bear proof. Resistant is the gold standard here.

IRA FLATOW: You mean a bear can get into anything sooner or later.

ALEX DAVIES: Theoretically. I’m sure that in the world there is a bear-proof product. But I don’t think anyone wants the liability of saying there is no bear on Earth who can’t get into this thing.

IRA FLATOW: [LAUGHS] All right, you’ve got my interest. You have to walk me through how a bear tests a product.

ALEX DAVIES: So let’s say I’ve created a new kind of garbage can. You know those garbage cans you tend to see in national parks where the latch to open it up is under a little piece of metal? Those are made to keep bears out because their paws can’t get in there.

But let’s say I’ve got some clever new design that makes it easier for humans to open and that I’m pretty confident a bear can’t get into because I’ve thought about, OK, this is how strong a bear is. This is what it might do. But to actually get a little seal on it that says, This is certified as bear resistant by the Interagency Grizzly Bear Committee, which is a federal consortium of agencies–

IRA FLATOW: Thats a real thing.

ALEX DAVIES: That’s a real thing. I bring it to this grizzly bear sanctuary, and I fill it up with fish and honey and dog treats and all sorts of stuff that bears like and that they can smell and want to get into. You give it to the bear, and you give them one hour to get into it. And you let them do whatever they want to try and get into it.

And the metric you’re looking for here is bear contact time. This is a world full of little bits of jargon like that. Bear contact time counts if the bear is pounding on it, clawing it, mauling it, biting it, jumping up and down on it, or doing what’s called the CPR technique, which is where he puts his front paws on it and pumps up and down like you’re doing CPR on a person.

IRA FLATOW: No kidding.

ALEX DAVIES: All of that counts toward bear contact time. But if the bear just walks away or sits there licking it or just kind of stroking it, none of that counts. And if you get through one hour of bear contact time and your product survives unopened, you get the seal of approval.

IRA FLATOW: Besides the bear proofing or resisting of objects, one example in your book that flies off the page for me is how airplane engines are tested against birds flying into them. They use dead chickens, right?

ALEX DAVIES: So bird strikes are a massive problem for jet engines. And so what the FAA did some number of decades ago was they did a big survey of what kinds of birds were actually flying into airplanes and what kind of other animals were being hit by airplanes to figure out what the threat landscape looked like.

And based on that, they created a set of three tests that a jet engine has to pass. It has to be hit with a volley of 16 pretty small birds, a volley of eight medium-sized birds, and it has to be hit with one 4-pound bird. And if the jet engine survives these tests or retains some amount of its power, or at the very least doesn’t explode upon being hit, it passes the test.

And the way you recreate a bird flying into a jet engine at takeoff speed, because you’re not going to fly jet engines on planes into flocks of birds– it would be tricky logistically and also obviously super dangerous– what you do instead is you accelerate the bird. And the way you accelerate a bird is with a compressed air cannon. And they load a chicken typically is what represents that 4-pound bird. And they shoot it out at something like 220 miles an hour into the jet engine and see how it does.

IRA FLATOW: Why not geese or something like that?

ALEX DAVIES: Here’s where you get all of the little problems with what’s called the bird ingestion test. And it’s not just this test. These are the real tensions at the heart of all product testing, is that you have these balancing things you’re trying to do of what I call similarity and workability.

So similarity, the principle there is make the test as close to the real world as you can. And so that’s why you have a cannon shooting a bird at about 220 miles an hour because that’s roughly the speed of a jet at takeoff. So that’s good similarity.

Workability is make a test reproducible. You want to know that the test data you’re getting is fairly comparable between one test to the other, which is why you tend to use chickens, because it’s very easy to get a 4-pound chicken.

IRA FLATOW: Right. Right.

ALEX DAVIES: And the standard only calls for a 4-pound bird. So you’re not going to load a goose into the air because a goose is going to weigh more like 10, maybe 12, maybe 8 pounds, somewhere in there. And that’s a problem with the standard.

IRA FLATOW: Right. Let’s go to the other side of the spectrum because you visited a lab testing bird-proof glass. I mean, how do you do that test? Are you shooting birds out of a cannon again at the glass?

ALEX DAVIES: So this is about getting birds to avoid getting hurt rather than accepting that they’re going to get hurt. So this is about the development of what’s called bird-safe glass. So something like a billion birds in the US die every year from flying into glass. And this is a particular problem with skyscrapers, which are huge and have a lot of glass and often stand in the middle of bird migratory patterns or just the places where birds live.

The battle here is that building designers and the people actually putting these glass things in hate the idea of bird-safe glass not because they hate birds but because it tends to not look that great. They don’t like the idea of putting dots all over their windows. They want a clear, beautiful view.

So what they’re trying to do is create bird-safe glass that is visible to birds but isn’t terrible looking to humans. Some use little dots. Some use bigger dots or stripes. Or sometimes people are experimenting with ultraviolet markings, which some birds can see but not all birds can see. But at least no humans can see it.

And the way they test whether or not this works is they bring it to this lab in Chestertown, Maryland, and they have a bird testing tunnel, which looks like a shipping container. And at the far end of it are two panes of glass. There’s always one clear pane that represents standard glass, and on the other side of it is the test glass.

And the people running it capture wild birds with these little nets, and they put them into this tunnel. And the bird naturally wants to fly out, and it’s flying toward the clear glass. And they measure, does the bird go toward the clear glass? Or does it go toward the marked glass?

And for the record, they’re not flying into the glass. They’re netting a few inches in front of it. So they fly into the nets.

IRA FLATOW: No bird was harmed in this experiment.

ALEX DAVIES: Exactly. No, these people who run this test love birds. And if half the birds are flying toward the control and half the birds are flying toward the new design glass, you know it’s not working. But if all of the birds are flying toward the clear glass, that shows that they see the design as something they shouldn’t fly into, which means it is working.

IRA FLATOW: After the break, more on the wild world of test engineering. Don’t go away.

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So who comes up with the safety standards for a product? For example, let’s say a lawn mower. I mean, you don’t want to get your hands in there. Who comes up with the safety standard for it?

ALEX DAVIES: There is no one person. And very disappointingly, there’s no Moses coming down the Mountain with the tablets written down. This is very human, very messy work, and it’s almost always the result of compromise.

So you brought up lawn mowers, and this is a story I write about in the book, which is, soon after the creation of the Consumer Product Safety Commission in the early 1970s, they were charged with making all consumer products at least reasonably safe or not horribly dangerous, at least. And they looked at the problem of lawnmowers, which is that a lot of people were getting injured because they would mow their lawn. The shoot would get clogged up with wet cut grass, and they would reach in with their fingers–

IRA FLATOW: [INHALES]

ALEX DAVIES: –to clear it out. And then their fingers would hit–

IRA FLATOW: Oh no.

ALEX DAVIES: –the blade, and they would lose a fingertip or get a pretty rough laceration. And so the CPSC says, well, the obvious solution to this is a dead man stop, which is now, if you’ve used a lawn mower, you notice, if you take your hands off it, the blade automatically stops.

No one disagreed with this, but the question was, how quickly does the blade have to stop? Does it have to stop in half a second? Does it have to stop in 10 seconds?

So the CPSC goes, OK, well, let’s take science to this problem. And they ran all these studies. They brought in people, and they had them push around fake lawnmowers. And they said, OK, now reach down to the chute.

And they would time how long it took them. And they ultimately said, we think about three seconds is a fair time to target. And we think it’s technically achievable with the technology we have now, and we think it shouldn’t add too much cost to do this. And then they bring it out for public comment.

And what always happens with standards and public comment is consumer advocates and say, three seconds, are you crazy? It should be 1.5 seconds most. And the industry says three seconds. Are you crazy? It should be 7 at least.

And we end up with three because it’s kind of a negotiated standard. It’s between what’s the best thing possible and what’s the most reasonable thing for business. And depending on the era, this was a time when government regulations actually had a lot of force, before Reagan came in and Clinton came in and we got a lot of deregulation around this stuff.

So politics plays a role. Economics plays a role. Cultural mores play a role. And oftentimes the big question is, who’s at risk here? And how grave is the risk?

IRA FLATOW: One safety feature that is ubiquitous– and this actually drives me crazy. I’ll tell you a secret– is the kid-proof medicine bottle because, when you get to be seniors, I know a lot of seniors my age, they cannot twist open a kid-proof medicine bottle because they have arthritis or their fingers are not working. Well, what kind of testing goes in to figuring out how to make a bottle that’s hard for kids to open and I wouldn’t say easy for adults, just possible for adults, to open?

ALEX DAVIES: Well, there are two tests there. One is you give it to a bunch of kids, and the other is you give it to a bunch of older people.

And the test with kids is pretty simple. You bring in a panel of 50 or so three, four, five-year-olds. And they’re told, see if you can open this. And you give them 10 minutes or so, and you just time them and watch them.

And if they don’t get in after 10 minutes, you can pause and say, oh, you can use your teeth. Or the adult opens it in front of them and closes it in front of them to represent what’s actually going to happen in the household. And so the standard there is 85%.

If that thing can keep out 85% of these kids, it passes. And the 85% there is going to feel pretty low to a lot of people, including me, as the father of a baby who’s about to turn one-year-old and likes to put things in her mouth. That doesn’t feel quite high enough, but it can’t go much higher because then you’re going to make the second test almost impossible to pass because you could make something that no kid can open but not that someone who’s 75 years old with arthritis can open.

And so that’s where the second test comes in, is a new design has to be tested by kids to make sure they can’t get into it and also by adults to make sure they can get into it. And the reason you don’t push that 85% up much higher is, one, it would make it harder for adults to open. But if it went much higher, there are people who say, well, you introduce a whole new kind of risk, which is that it’s so difficult for an adult to open that, when they do get it open, they’re not going to close it again because they don’t want to go through that pain again.

And so it’s all a compromise. No one wants kids to get into these things. But you have to make sure that it’s practical enough for the person who actually needs to get into there, that they can do it and they can do it easily enough that they don’t mind doing it.

IRA FLATOW: Earlier, we talked about the meticulous testing airplanes undergo, and you wrote about it even in more detail in the book. But I can’t help but think about what happened a couple of years ago when a door blew off a Boeing 737 MAX while it was in flight. Has the golden age of test engineering come and gone?

ALEX DAVIES: I think it’s here. And I think we’re better than ever at testing things. The problem is that testing doesn’t happen within a vacuum. Testing is a social process.

But I think what happened with Boeing is that the test engineers didn’t have as much clout as I think they did at an earlier time in Boeing’s history. And so it’s not that we’re past the golden age of testing. It’s that maybe we’re past the golden age of listening to test engineers.

IRA FLATOW: All you have to do is remember back to the shuttle disaster and the o-rings that engineers warned about and no one listened to them.

ALEX DAVIES: Listen to your engineers.

IRA FLATOW: Well, this is a really fascinating book for geeks like me who love to see how things work, love to test them. I want to thank you for taking time to be with us today, Alex.

ALEX DAVIES: Yeah, thanks so much for having me.

IRA FLATOW: Alex Davies, journalist and author of the Kobuk the Destroyer– and Other Tales from the Wild Unseen World of Test Engineering. This episode was produced by Shoshannah Buxbaum. We’d love to what you think of the show, or if you have any burning scientific questions you want us to help answer, give us a call at 877-4-SCIFRI. That’s 877, the number 4, SciFri. Our listener line is always open.

I’m Ira Flatow. We’ll catch you next time.

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