# Measuring "Controlled Explosions" **URL:** \ **Category:** Factual Questions\ **Created:** [May 15, 2016, 3:38pm UTC](https://boards.straightdope.com/t/measuring-controlled-explosions/754848 "2016-05-15T15:38:45Z")\ **Posts on this page:** 7\ **Page:** 1
**Author:** ![Kiber](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/kiber/32/317_2.png) [@Kiber](https://boards.straightdope.com/u/Kiber)\ **Post date:** [May 15, 2016, 3:38pm UTC](https://boards.straightdope.com/t/measuring-controlled-explosions/754848/1 "2016-05-15T15:38:45Z")
For those who don’t know - todays Manchester United game was cancelled after a suspicious package was found at the stadium. Apparently this is the first time a Premier League game has been cancelled for security reasons. This [news feed](http://www.telegraph.co.uk/football/2016/05/15/manchester-united-game-abandoned-after-suspect-package-found/)notes that the package (some combination of pipes / cell phone) will undergo a controlled explosion. My question: Can they measure the force of the controlled explosion to determine if the suspicious package had explosives in it? I’m imagining something like a scaled up [bomb calorimeter](https://en.wikipedia.org/wiki/Calorimeter#Bomb_calorimeters)that could measure the energy of the explosion, compare it to the amount of explosives added by the police, and determine how much extra energy, if any, was present. Or at least, at a high level, determine if there was likely more energy than the police added. Surely it must be useful for the police to know if there was actually any explosive in the suspicious package. ---
**Author:** ![Baron\_Greenback](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/baron_greenback/32/48_2.png) [@Baron\_Greenback](https://boards.straightdope.com/u/Baron_Greenback)\ **Post date:** [May 15, 2016, 5:22pm UTC](https://boards.straightdope.com/t/measuring-controlled-explosions/754848/2 "2016-05-15T17:22:50Z")
The point of a controlled explosion is to separate the device into its component parts. It’s a bad day at the office if the suspect device actually goes off. ---
**Author:** ![smithsb](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/smithsb/32/12107_2.png) [@smithsb](https://boards.straightdope.com/u/smithsb)\ **Post date:** [May 15, 2016, 7:49pm UTC](https://boards.straightdope.com/t/measuring-controlled-explosions/754848/3 "2016-05-15T19:49:05Z")
Real world testing, we’d use a couple of strings of pressure sensors, high speed film cameras, fragment throw analysis, and maybe ground shock measurement. That’s for testing buildings, barricades, and configurations of material. Base testing of the explosive compound is at the laboratory level and scales pretty well. Here, they have an accurate picture of the device (good); they’ll estimate the quantity of contained explosives; add in their contribution; and assume the worst (everything goes instead of interruption); figure up a safe area for shock wave and fragment throw and have a go at it. They may not know the exact explosive (if it’s red mercury, all bets are off) but there isn’t a huge difference between what’s available to a terrorist. They should probably assume it’s TATB which is pretty potent. They would do an analysis of tragment later to determine the compound used. As for a measurement of the explosive/explosion - no. Not in the cards for a short time event like this impacting civilians. Any results from filming, debris fields, compounds would be added to databases of known IEDs or bombings. ---
**Author:** ![PastTense](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/pasttense/32/14550_2.png) [@PastTense](https://boards.straightdope.com/u/PastTense)\ **Post date:** [May 15, 2016, 11:19pm UTC](https://boards.straightdope.com/t/measuring-controlled-explosions/754848/4 "2016-05-15T23:19:00Z")
> [@](#): > > A suspicious item found in Manchester United’s Old Trafford stadium ahead of a key soccer game was actually a training device, police said on Sunday. > The discovery of the “incredibly lifelike explosive device” Sunday prompted the evacuation of United’s game against AFC Bournemouth, which was then canceled. > “Following today’s controlled explosion, we have since found out that the item was a training device which had accidentally been left by a private company following a training exercise involving explosive search dogs,” Assistant Chief Constable John O’Hare of the Greater Manchester Police said in a statement. > **[Man Utd: ‘Bomb’ scare cause dubbed ‘fiasco’ | CNN](https://edition.cnn.com/2016/05/15/world/uk-manchester-united/)** > > Greater Manchester Mayor Tony Lloyd calls for inquiry as to how an “incredibly lifelike explosive device” was left at Manchester United’s Old Trafford stadium. Anyone here would probably label a training device clearly so no one would get confused wouldn’t they? ---
**Author:** ![Joey\_P](https://avatars.discourse-cdn.com/v4/letter/j/919ad9/32.png) [@Joey\_P](https://boards.straightdope.com/u/Joey_P)\ **Post date:** [May 15, 2016, 11:36pm UTC](https://boards.straightdope.com/t/measuring-controlled-explosions/754848/5 "2016-05-15T23:36:37Z")
Explosive search dogs? > [@PastTense](#): > > [http://edition.cnn.com/2016/05/15/world/uk-manchester-united/](http://edition.cnn.com/2016/05/15/world/uk-manchester-united/) > > Anyone here would probably label a training device clearly so no one would get confused wouldn’t they? Or better yet, the training devices should have been counted/recounted after the private testing company left the facility so they could make sure they brought them all back with them. Hindsight is 20/20 and all, but you don’t want a real terrorist to be able to right “FAKE BOMB” on the side of a real bomb and have someone just move it to a closet with plans of dealing with it next week. Of course, now that I think of it, maybe fake/testing bombs could somehow be registered with the jurisdiction that they’re in and be given some kind of unique number or seal that stays with it so in this scenario the bomb squad could have shown up and recognized it right away. ---
**Author:** ![Isilder](https://avatars.discourse-cdn.com/v4/letter/i/cc9497/32.png) [@Isilder](https://boards.straightdope.com/u/Isilder)\ **Post date:** [May 17, 2016, 4:26am UTC](https://boards.straightdope.com/t/measuring-controlled-explosions/754848/6 "2016-05-17T04:26:14Z")
OP … yes they have a video camera record the explosion. The shock wave itself measures the explosion… its obvious from the video of the explosion in slomo how the controlled explosion went. News today… the head of the security firm said two things today - it was labelled, with HIS mobile phone number on it. He wasn’t called, and no one connected up the training excercise in the last week with the little package labelled “Training … ACME SECURITY, please call ACME !”. - The head himself counted the number of training devicie recovered, he checked his bag, he counted one, he returned one. The mistake was that when he took his bag to the site, he had a device was already in it, so when he checked he had one, he didn’t recover the one actually used in training. This is a repeat of the sydney ferries fiasco… Oh, oops, it was a training device left behind… well its happened other times too… training/test packages left in travelers luggage, and all that. ---
**Author:** ![Kiber](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/kiber/32/317_2.png) [@Kiber](https://boards.straightdope.com/u/Kiber)\ **Post date:** [May 17, 2016, 7:31am UTC](https://boards.straightdope.com/t/measuring-controlled-explosions/754848/7 "2016-05-17T07:31:18Z")
Thanks all for the responses. I hadn’t realized so much could be learned from high speed video and ground shock analysis. But it makes perfect sense. As an aside - the match will be made up tonight. If Manchester United can win by 19 goals or more, they will finish in the top 4 of the Premiere League. Should be quite a game . . . 😉