Episode 14 Watchdog Test House


Episode 14

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Take a look around your home.

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Can you be sure that every appliance is safe?

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Is everything a company tells you about a product true?

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And are you getting the best value for your money?

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With the help of the country's top experts, we're going to see

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what it takes to test the household products we use every day.

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We'll discover how they're pushed to their limits...

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..we'll put the makers' claims on trial...

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..and show you how to make your money go further.

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You'll find these products in any ordinary house,

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but this is no an ordinary house,

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and no ordinary street.

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This is the Watchdog Test House.

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Hello. We're deep inside one of Britain's leading science centres.

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Here at the Building Research Establishment, some of the products

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and materials that we use every day are put to the test

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to make sure that they're safe,

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environmentally friendly and that they don't fall apart.

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Coming up on today's programme,

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smoke alarms. A staggering one in four fail to go off in fires

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attended by the fire brigade.

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The smoke was coming out of the loft hatch quite severely,

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and the smoke alarms didn't go off at all.

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How do manufacturers try to ensure they're going to be fail-safe?

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Fitness trackers - they claim to count calories and steps.

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They're a fantastic motivation point. Track your calories

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every day and try and improve on it day after day, run after run.

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But how accurate are they? We put three products through their paces.

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And exploding oven doors - no stranger to Watchdog...

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..but aren't they supposed to be made of toughened glass?

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Smoke alarms - the best way you to protect you

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and your home against the threat of fire.

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The good news? About 85% of households have them installed.

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The bad news? They don't always go off.

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The upstairs of the house was full of smoke.

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I couldn't see where I was going.

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Darren King was spending a Sunday afternoon at home with his two

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children when his house caught fire.

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My two sons were out the front playing,

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and my eldest son came running in, just to say, "Daddy phone 999 -

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"there's smoke coming out the roof."

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When Darren went outside, he soon realised the fire was

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actually inside the walls of the house.

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The fire was actually started down in the bottom corner

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of the threshold.

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So I tried to put that out, and then when I came inside,

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I put my hand on here and noticed there was a lot of heat

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and I could hear crackling.

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I realised at that point then that the fire was going all

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the way up the cavity wall.

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Before long, the flames had reached the roof.

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That's how high the fire actually came up from the ground floor

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back door,

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and it's started burning through the wooden framework

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of the actual house.

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Darren called 999, and by the time the fire brigade had put

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the flames out, the house was full of smoke,

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but the smoke alarm was faulty and it never went off.

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Luckily the fire was in the afternoon and not in the evening,

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because if we'd been in bed, we wouldn't have noticed.

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The smoke alarms wouldn't have gone off,

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and we may not have got out of the house alive.

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Fire brigade statistics show that in more than one in four

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of the house fires they attend where a smoke alarm was present,

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it failed to go off.

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In Darren's case, the alarms were faulty,

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but there can be plenty of other reasons too.

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Smoke alarms have been going off, creating a false alarm,

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and people have actually taken the batteries out

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because of the nuisance factor, and forgot to put them back.

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There are also issues with inadequate siting within the homes.

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Smoke alarms must be sited where they can give adequate coverage

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and protection, so they can be heard.

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But of course that probably won't mean that it covers

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every room within a house.

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You also need to think about which type of alarm you buy.

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Broadly, there are two types - ionisation and optical,

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and fire and rescue services would recommend the fitting

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of optical-type detectors in all but specific circumstances.

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That's because optical detectors are safer in detecting

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a broader range of fires.

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Either way, you're better off with an alarm than without,

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as you're four times as likely to die in a house fire

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if you don't have a smoke alarm.

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And to make sure they operate effectively, every model

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on the market has to be thoroughly tested before going on sale.

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Later in the programme, we'll be at the British Standards Institution,

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to find out how.

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Now, fitness trackers.

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They monitor your activity throughout the day

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and tell how many calories you burn.

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They're marketed as the smartest way to stay active.

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But just how accurate are they?

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Well, Sophie, if you're anything like me and can't afford your own

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personal trainer to keep on top of your exercise regime, you may

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want turn to one of these nifty little gadgets for help.

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Just ask this lot.

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I just tell it I'm going running,

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and it'll basically keep track of how far I've gone,

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the speed that I'm going,

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and then it gives me a breakdown of my run at the end of the run.

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If you're the sort of person that likes to keep on top

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of things, see your progress and so on,

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I think these devices are excellent.

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They're a fantastic motivation point. Track your calories

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every day and try and improve on it day after day, run after run.

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But just how reliable are these devices?

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To find out, we've come to Brunel University, where,

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with the help of Richard Godfrey - a lecturer in sports psychology,

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Tom - a triathlete...

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Hi, Tom. Nice to see you. I'm Richard.

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..and Chris - the lab technician,

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we're going to put two of their many claims to the test -

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calories burnt and the number of steps taken.

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Tom will be wearing three products chosen from the UK's

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leading on-line retailers -

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the cheapest we could find, the V-fit WSG pedometer,

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costing just over £6,

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a mid-range product, the Fitbit Zip, costing £49.99,

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wand the top-of-the-range Nike+ FuelBand

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which costs £129 -

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all of which claim to monitor both calories and steps.

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First up, calories.

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Chris inputs Tom's vital statistics into all three devices

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according to the manufacturers' instructions.

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Then it's time for the work-out.

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Three, two, one, go.

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He's first of all going to do ten minutes of walking

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at an easy pace, wearing the devices and having

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oxygen consumption measured at the same time.

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He'll then have a bit of a break before we get him to do

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another ten minutes, this time at a higher intensity, just a jog,

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slow jog, and then he'll have another break,

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after which we'll do another ten minutes, this time at a faster jog.

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As Tom exercises, his muscles use oxygen to burn fuel - or calories.

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The more oxygen consumed, the more calories burned.

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Therefore, by tracking Tom's oxygen consumption

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throughout his work-out, Richard will have a scientifically accurate

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measure of calorie expenditure.

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He can then compare that to what our three devices say.

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Five, four, three, two, one, stop.

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With the work-out complete

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and the calorie data captured from all three devices,

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it's on to the second part of the test...

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There we go. That's got to be better.

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..steps taken.

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For this, Tom moves onto another crucial bit of scientific kit -

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the fire escape.

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According to Government guidelines, it's recommended that you take

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around 10,000 steps in a normal day.

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That's roughly the equivalent of a five-mile walk.

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So having an accurate idea of how many you've taken is important.

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We know that it takes exactly 152 steps to go to the bottom

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and back to the top.

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What we don't know is how many steps our devices will think he's taken.

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So just to make sure we're accurate, we do the test twice.

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With the tests now complete,

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it's time for Richard to crunch the numbers.

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And we'll be bringing you the results later in the programme.

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Next, exploding oven doors -

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a sudden bang, with glass spraying out across the kitchen floor.

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It's enough to give anyone a fright.

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But why does this happen when oven doors are made from toughened glass?

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A question for Lynn Faulds Wood.

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ARCHIVE: 'Welcome to Watchdog. In tonight's programme...

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'All these people have written to us.'

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In the 1980s, oven doors made of glass were still a bit of a novelty.

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Now, you might not have noticed, but over the past few years,

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there's been a revolution in the way our cookers are designed.

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But by 1988, hundreds of Watchdog viewers were complaining

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that so-called toughened glass in their oven doors

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had shattered without warning.

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There was a tremendous crashing noise. I turned round to find

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that the front glass of the cooker had exploded out, and he was

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actually standing in all these small pieces of very hot glass.

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Imagine that happening in your kitchen.

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And we discovered it was down to the way the glass had been

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fitted into the oven door.

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We go to the bottom oven, the glass is held in with these clips and

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there's no seal underneath, so it's pressing metal on the glass on both

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sides. Finally, if I shut the door, I think you'll see the problem.

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LOUD SMACK

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That's not good enough -

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it's stressing an already badly fixed door.

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With criticism like that, no wonder manufacturers were persuaded

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to spend millions improving door seals, hinges

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and fittings to reduce the stress on the surface of the glass.

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Philips even asked me to fly to their Italian factory

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to see the changes they'd introduced.

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The slot here that the glass fits into, before it was just two metal

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pieces. Now it's a continuous metal piece all the way along. Much better.

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But what is it about toughened glass that makes it prone to shattering

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so spectacularly if fitted badly to the oven door?

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Toughened glass is used in all sorts of modern inventions,

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from patio doors to windows in your car,

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but its origins date all the way back to the 17th century.

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Prince Rupert of Bavaria came across the phenomenon by accident.

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He found dropping hot molten glass into cold water formed

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tadpole-shaped droplets.

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These "Rupert drops", as they became known,

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have remarkable properties.

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CLINK The fat end is surprisingly strong.

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As you can see, it has survived the impact.

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The thin end, however, shatters

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at the slightest touch.

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The drop has disappeared. It has completely shattered.

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Why? When the hot glass is plunged into the cold water,

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the outside hardens really quickly.

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The glass on the inside, though, cools much more slowly, and like

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a coiled spring, it pushes against the already hardened outside layer.

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It's this tension between the inner glass pushing out against

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the already hardened outside surface that makes the droplet so strong.

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But if you damage that outside surface,

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the inner tension is released,

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and the droplet explodes into tiny, harmless fragments.

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And that's exactly the principles on which toughened glass is based.

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The glass is taken up to about 700 degrees

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and cooled very quickly with air jets.

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This has the same effect, where you get compressive layers

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under the surface and tension in the centre.

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At any point, if any scratch goes into that compressive layer,

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the glass will break.

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But it was its ability to be both strong and also break into harmless

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fragments that caught the attention of the car industry.

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This is what can happen with a windscreen

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made of toughened safety glass.

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As more cars came onto the roads in the '20s and '30s,

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the numbers of accidents increased,

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and with many injuries being caused by the windows breaking

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into razor sharp pieces, toughened glass seemed the perfect solution.

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The first British Standard for this glass in cars

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was introduced in 1939.

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Demand increased in the 1960s, as regulations were introduced actually requiring it

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to be used in cars and in certain windows in buildings.

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Today, wherever it's used, to meet current European standards,

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toughened glass needs to be strong enough

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to withstand the force of anything that might be thrown at it,

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and when I say anything...

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One, two...

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The weight of it, being 50kg,

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is very similar to a child running into a window, so it will

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demonstrate that that window or that patio door can survive that impact.

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But again, despite its vast strength,

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compromise that outer layer with a couple of scratches

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and it becomes extremely vulnerable

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and collapses into those harmless little cubes or dice.

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So looking back to those poorly designed oven doors,

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those exposed metal rims and clips that were

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pressing on the toughened glass were in fact compromising

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the surface in the same way as that scratch.

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And the result?

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Although the design of oven doors has much improved,

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toughened glass will always have the potential to become

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'compromised. But whether it's been scratched or chipped during

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'manufacture, or even as a result of aggressive cleaning...'

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At least you know with toughened glass

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that if it does shatter, it won't go into long, sharp shards

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but rather into something safer like this.

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If you're thinking about buying a car, there's certainly

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an awful lot to choose from,

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so where do you start, and is it ever good value to buy a new one?

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Well, Emma Butcher from What Car? is with us now. Is it?

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Well, surprisingly, sometimes it can, yes.

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Most people would think that buying new didn't represent good value

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at all over buying used, because, of course,

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when you drive away from the forecourts you get that massive

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hit of depreciation that can be up to 20% of the cost of the car.

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However, there are some amazing discounts out there at the moment,

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because manufacturers and car dealers,

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they really want you to buy a new car,

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and they're incentivising that, so that can be anything from a finance

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package with ultra-low interest rates, sometimes even 0% interest,

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to throwing in some free insurance or free servicing.

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So, potentially, you could be getting a better deal on a new car.

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What about the claims that car manufacturers make?

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Is it easy to compare them?

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Well, it's a bit of a lottery. You would think that you could

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benchmark them, but our research has found no,

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so those MPG figures that you see

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advertised basically come from Government-mandated laboratory tests

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which every car-maker must put its car through before they go on sale,

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but because they're conducted in a lab, that doesn't really reflect

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what happens when you're out in real traffic conditions.

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At What Car? we've tested about 400 different engines now,

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and we take cars out on the road, in real traffic,

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and work out their true MPG based on their tailpipe emissions,

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and we found that on average there can be

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a 17% shortfall from what is actually claimed that a car can do

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to what it actually achieves in real life.

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So when you're buying a new car, what should you look out for?

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First of all, make sure that you take the car out for a test drive.

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Don't ever buy without doing that.

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It's a really good idea to take someone with you who can

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distract the sales person so you can concentrate on the drive,

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and, similarly, you might want to leave the kids at home

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if you think they'll distract you as well, although do take

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along the buggies and the car seats to see what kind of a fit they make.

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-Emma, good advice. Thank you very much.

-Thank you.

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Earlier, we put three fitness trackers through their paces.

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From the cheapest to the most expensive, they all claimed

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to count the number of calories burnt and the number of steps taken.

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So how did they perform? Let's find out.

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First up, counting steps.

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We asked triathlete Tom to climb up and down

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this 152-step fire escape twice.

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The actual number of steps is 304,

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but how many did our devices record?

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Starting with our most expensive product, the Nike+ FuelBand,

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costing £129.

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It didn't do quite so well, counting 281 steps -

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23 under the actual number.

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Quite surprising for a device as expensive as it is.

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The Fitbit Zip, our mid-range product, costing £49.99,

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did much better - it was only out by two steps.

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As for our cheapest product, at just over £6, the V-fit WSG pedometer...

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In terms of counting steps, the pedometer did really well indeed.

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304 steps were taken and it counted 305,

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so that's really good for a relatively cheap device.

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Yes, our cheapest device actually performed the best.

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It miscounted by just one step over the course of the two tests.

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The pedometer's quite a simple device

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and it's therefore best at measuring simple linear movement,

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so simply counting steps is what it does very well.

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So if it's just counting steps you're looking for,

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a cheaper product may well be perfectly adequate.

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But how good were the devices at measuring calorie-burn?

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Now, remember, during his work-out Richard asked Tom to walk,

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jog and run. He monitored Tom's oxygen consumption

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throughout as a measure of fuel consumption

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and therefore a more accurate record of calorie-burn.

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He then compared that to what the three devices said.

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Three, two, one, stop.

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In terms of estimated calorie expenditure,

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the Nike+ FuelBand, the most expensive device, did the best.

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With our laboratory-based kit, we measured 248 calories.

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The Nike FuelBand measured 310, so 62 more, which is actually very good

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for a device of that type.

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Our cheapest product, the V-fit WSG pedometer, struggled.

0:19:220:19:27

Whilst our laboratory based kit measured 248 calories, the V-fit

0:19:270:19:31

only measured 125 - a difference of 123 calories.

0:19:310:19:35

But it was the mid-range product, the Fitbit Zip, that performed the worst.

0:19:370:19:41

It measured 432 - an overestimation of 184 calories.

0:19:430:19:48

None of the devices was completely accurate.

0:19:520:19:54

However, the Fitbit Zip was the worst one,

0:19:540:19:56

overestimating by almost half a chocolate bar.

0:19:560:19:58

So if you used that device, you'd actually think you'd expended

0:19:580:20:01

a lot more energy than you really had.

0:20:010:20:03

But according to Richard, it might not be all bad news.

0:20:050:20:09

Well, measuring calories is very useful, but being consistent

0:20:090:20:12

is also important, and the device has to measure consistently.

0:20:120:20:15

So you have to know that it's you that's improved in any change

0:20:150:20:18

that you see, and not some quirk of the device.

0:20:180:20:20

So, time for one final test - consistency.

0:20:220:20:25

We had Tom repeat the work-out to see if the devices gave

0:20:250:20:28

the same measurements for calorie-burn the second time around.

0:20:280:20:31

First up, our cheapest product, the V-fit WSG pedometer.

0:20:320:20:37

Although again it wasn't very accurate,

0:20:370:20:39

it was at least consistent, as it gave an almost identical

0:20:390:20:42

incorrect calorie reading on our second test.

0:20:420:20:44

Next, our mid-range product, the Fitbit.

0:20:450:20:48

Not only was it the least accurate

0:20:480:20:50

when counting calories, it was also the least consistent.

0:20:500:20:53

For both those work-outs, you'd expect to see

0:20:530:20:55

the same results - you want to see reproducibility.

0:20:550:20:58

That didn't happen. There was a big, big difference,

0:20:580:21:00

which means it's not a particularly reliable device

0:21:000:21:02

and it doesn't assess performance particularly well.

0:21:020:21:05

As for the Nike+ FuelBand, our most expensive product, not only was it

0:21:050:21:09

the most accurate, it was also the most consistent -

0:21:090:21:13

at least in our test.

0:21:130:21:14

The Nike FuelBand did much better. It showed greater consistency,

0:21:140:21:17

and that's exactly what we want in devices of this type.

0:21:170:21:19

That's the name of the game.

0:21:190:21:21

Fitbit told us they are surprised

0:21:210:21:23

and disappointed with the results of our test, which they say

0:21:230:21:26

do not represent the normal experience of their customers.

0:21:260:21:29

They say the tracker has undergone thousands of scientific tests,

0:21:290:21:33

should be at least 95% accurate,

0:21:330:21:36

and they do everything to ensure customer experience is positive.

0:21:360:21:40

But whatever the device you choose to wear,

0:21:400:21:42

according to Richard, there is at least one benefit they all share.

0:21:420:21:45

With these devices, they're incredibly motivating.

0:21:450:21:47

You can upload information, you can share it with family and friends,

0:21:470:21:51

you can introduce elements of competition -

0:21:510:21:52

all of this means these devices are motivating.

0:21:520:21:56

So maybe these little devices CAN be your own personal trainer -

0:21:560:21:59

just as long as you're not always expecting a precision calorie-count

0:21:590:22:02

along the way.

0:22:020:22:03

Back to smoke alarms now.

0:22:080:22:10

You're four times more likely to die in a house fire

0:22:100:22:14

if there is no working smoke alarm.

0:22:140:22:16

So what do manufacturers do to try to ensure they're fail-safe?

0:22:160:22:20

Test them, of course.

0:22:200:22:22

The British Standards Institution in Hemel Hempstead.

0:22:220:22:26

Here they don't just test products - they help write the rule book,

0:22:260:22:30

known as the Standards.

0:22:300:22:31

BSI was established in 1901.

0:22:310:22:34

At the time, it was the world's first national standards body,

0:22:340:22:37

and remains today the UK national standards body.

0:22:370:22:41

For a smoke alarm to meet current safety standards,

0:22:410:22:43

it has to pass more than 40 tests.

0:22:430:22:46

It's critical that these products do actually

0:22:470:22:50

perform the function that they're designed for.

0:22:500:22:52

The last thing you want is to have a smoke alarm fitted

0:22:520:22:55

in your house which doesn't go off in the event of a fire.

0:22:550:22:58

Today we're going to be demonstrating some of those tests,

0:22:580:23:01

using a mid-range smoke alarm currently on the market

0:23:010:23:04

for about £20.

0:23:040:23:06

We're starting with the most important piece of machinery -

0:23:060:23:09

the smoke tunnel.

0:23:090:23:10

We used to actually create real smoke for the tunnel,

0:23:110:23:15

using this heated bar, here.

0:23:150:23:17

Now we use atomised liquid paraffin.

0:23:170:23:19

It's a much more controllable way of producing simulated smoke.

0:23:190:23:24

So, in goes the alarm,

0:23:240:23:26

then the smoke is blown gently around the tunnel,

0:23:260:23:30

not that you'll be able to see it.

0:23:300:23:32

It's very, very small quantities.

0:23:320:23:33

So we're talking literally parts of a million, here.

0:23:330:23:36

So when the smoke alarms are actually triggered, you wouldn't

0:23:360:23:39

be able to see with the human eye the smoke in the atmosphere.

0:23:390:23:43

The thickness of the smoke is gradually increased in order

0:23:430:23:46

to measure exactly how much is needed to set the alarm off.

0:23:460:23:50

ALARM BLEEPS

0:23:500:23:53

What we're looking for here is to make sure it doesn't go off

0:23:530:23:56

at too sensitive a level, otherwise, obviously, it would

0:23:560:23:58

be going off at all hours of the night, and giving false readings.

0:23:580:24:02

Effectively, it has to trigger at a higher point than 0.2dB per metres,

0:24:020:24:07

and it triggered at 0.87, which is technically a pass.

0:24:070:24:11

What we have to do now is take five more measurements,

0:24:110:24:14

and then we'll assess the results to ensure

0:24:140:24:16

the ratio between the highest and lowest trigger point isn't too wide.

0:24:160:24:20

Effectively, what we're looking for here is to ensure that the product,

0:24:200:24:24

once it's operated once,

0:24:240:24:25

will operate again in the future at the same levels.

0:24:250:24:29

Checking the consistency of the alarm in this way

0:24:290:24:32

is called repeatability.

0:24:320:24:34

Next, they need to find out whether it has any weak spots.

0:24:340:24:37

This box is the ionisation chamber,

0:24:370:24:40

so this is the actual detector of the smoke.

0:24:400:24:43

We want to ensure that regardless of where the smoke's coming in,

0:24:430:24:46

it will reach that chamber and the alarm will trigger.

0:24:460:24:49

And you can see that if the smoke enters at this point, it has

0:24:490:24:52

a lot of electronic components that it has to negotiate before it

0:24:520:24:55

will actually reach that chamber and detect smoke.

0:24:550:24:58

We'll put the product back into the smoke tunnel,

0:24:580:25:01

and we'll turn it round at 45 degree angles.

0:25:010:25:04

Once we've identified the worst point of access for the smoke,

0:25:040:25:08

we'll carry out the rest of the tests in that particular orientation

0:25:080:25:12

to ensure it's the worst-case scenario.

0:25:120:25:14

Once you know that an individual alarm works,

0:25:140:25:17

and in all positions, you need to be sure each one manufactured

0:25:170:25:21

is roughly the same. The way to do that?

0:25:210:25:23

Test another 20. And if they're sufficiently consistent,

0:25:230:25:27

it's time for extreme conditions.

0:25:270:25:30

What we're doing now is adjusting the temperature of the smoke tunnel.

0:25:300:25:34

We're going to do two tests in here.

0:25:340:25:36

We'll do a cold operational test at nought degrees C,

0:25:360:25:38

and a dry heat test at 55 degrees C.

0:25:380:25:43

If you have a product which is installed in a house and it's

0:25:430:25:45

a particularly cold night, we want to make sure that it will activate

0:25:450:25:49

when it's supposed to as well as it would do on a very hot, sunny day.

0:25:490:25:52

So once you know the alarm can sniff out smoke in all manner

0:25:520:25:55

of conditions, attention turns to sound.

0:25:550:25:58

And for that you'll need some peace and quiet.

0:25:580:26:02

This is one of our special test chambers.

0:26:040:26:06

It's called an anechoic chamber.

0:26:060:26:08

We're using it to measure the volume of the smoke alarm in this case,

0:26:080:26:12

and what we don't want to do is to have the sound

0:26:120:26:14

bouncing off the walls back to our measuring equipment.

0:26:140:26:17

We only want to hear it once, as it comes out of the actual alarm itself.

0:26:170:26:21

You can see the construction of the room here.

0:26:210:26:23

It's covered with these special foam cones,

0:26:230:26:26

which are designed to trap and absorb the sound.

0:26:260:26:29

It's a very strange feeling with the door shut,

0:26:290:26:31

because you literally can't hear anything.

0:26:310:26:33

You can hear the pulse of your blood in your ears,

0:26:330:26:35

and when you talk it sounds as though you're actually talking in your head,

0:26:350:26:39

because there's literally no echo at all.

0:26:390:26:41

HEARTBEAT

0:26:410:26:43

The perfect environment for accurately measuring noise.

0:26:430:26:46

ALARM BLEEPS

0:26:480:26:51

What we're looking for is a sound level in excess of 85 decibels

0:26:510:26:55

when measured at three metres from the alarm point.

0:26:550:26:58

What we can't do is exceed 110 decibels.

0:26:580:27:00

Basically, those parameters are set so that the alarm is loud enough

0:27:000:27:04

to be heard when it needs to be, but not so loud

0:27:040:27:06

that it becomes debilitating.

0:27:060:27:08

So, your smoke alarm detects smoke and makes the right amount of noise.

0:27:080:27:13

One last thing - is it robust?

0:27:130:27:15

Yes, that's our alarm being hit with a hammer.

0:27:150:27:19

What we're trying to do here is to replicate the kind of impact that

0:27:190:27:22

it might realistically experience during the course of its lifetime -

0:27:220:27:25

from the point of manufacture, transportation, installation.

0:27:250:27:29

You might drop it on the floor... All these things we take into

0:27:290:27:32

consideration, and we're trying to replicate the worst kind of impact

0:27:320:27:35

that it's likely to experience.

0:27:350:27:37

A single blow measuring 1.6 joules, to be precise.

0:27:370:27:42

And if it survives, you can always try shaking it to bits.

0:27:420:27:46

What we're doing is subjecting it to different

0:27:460:27:49

cycles of vibration in three different axes.

0:27:490:27:51

So forward and backwards, side to side, and up and down.

0:27:510:27:54

At the end of the vibration test, we'll do a visual inspection.

0:27:540:27:57

We need to make sure that the cover is still attached,

0:27:570:27:59

that the electronic components are still firmly fixed to the board.

0:27:590:28:02

And then what we'll do is put it back together,

0:28:020:28:05

put it into the smoke tunnel, and subject it to the same smoke tests

0:28:050:28:08

that we did previously, to make sure that it still activates

0:28:080:28:10

in accordance with the manufacturer's specification.

0:28:100:28:13

If you want more information on the safety of products in your home,

0:28:170:28:20

you can go to our website:

0:28:200:28:25

That's all for today. Thanks for watching.

0:28:280:28:30

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