# Is it dangerous to open a microwave door before the timer winds down? **URL:** \ **Category:** Factual Questions\ **Created:** [November 23, 2009, 2:25pm UTC](https://boards.straightdope.com/t/is-it-dangerous-to-open-a-microwave-door-before-the-timer-winds-down/518634 "2009-11-23T14:25:16Z")\ **Posts on this page:** 16\ **Page:** 1
**Author:** ![guizot](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/guizot/32/3636_2.png) [@guizot](https://boards.straightdope.com/u/guizot)\ **Post date:** [November 23, 2009, 2:25pm UTC](https://boards.straightdope.com/t/is-it-dangerous-to-open-a-microwave-door-before-the-timer-winds-down/518634/1 "2009-11-23T14:25:16Z")
A friend of mine freaked out when I did this recently. He acted as though doing this it lets radiation out that could be harmful. Setting aside that every microwave I know of turns itself off when you open its door, could “stray” microwave radiation really cause any harm? ---
**Author:** ![ftg](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/ftg/32/2801_2.png) [@ftg](https://boards.straightdope.com/u/ftg)\ **Post date:** [November 23, 2009, 2:36pm UTC](https://boards.straightdope.com/t/is-it-dangerous-to-open-a-microwave-door-before-the-timer-winds-down/518634/2 "2009-11-23T14:36:00Z")
[There is absolutely positively nothing to worry about.](http://www.repairfaq.org/sam/micfaq.htm#michldmeh) ---
**Author:** ![beowulff](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/beowulff/32/542_2.png) [@beowulff](https://boards.straightdope.com/u/beowulff)\ **Post date:** [November 23, 2009, 2:36pm UTC](https://boards.straightdope.com/t/is-it-dangerous-to-open-a-microwave-door-before-the-timer-winds-down/518634/3 "2009-11-23T14:36:14Z")
There’s an interlock that turns of the magnetron when the door is opened. If the interlock failed, you could get burned it you opened the door and got exposed to a full blast of microwaves. Still, I trust the interlock and do what you did all the time. ---
**Author:** ![Gyrate](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/gyrate/32/3588_2.png) [@Gyrate](https://boards.straightdope.com/u/Gyrate)\ **Post date:** [November 23, 2009, 2:37pm UTC](https://boards.straightdope.com/t/is-it-dangerous-to-open-a-microwave-door-before-the-timer-winds-down/518634/4 "2009-11-23T14:37:26Z")
I would be inclined to agree with you rather than your friend. Microwaves do not make your food “radioactive”; they just make it hot. Microwaves are “non-ionizing” radiation. Of course, if the oven is damaged in such a way that it continues to work with the door open, there’s always a risk of _you_ being “made hot” and getting burned (and then [this happens](http://i531.photobucket.com/albums/dd358/iwanttorentawombat/facemelt.gif)). But again, that’s a highly unlikely malfunction. ---
**Author:** ![HorseloverFat](https://avatars.discourse-cdn.com/v4/letter/h/8e8cbc/32.png) [@HorseloverFat](https://boards.straightdope.com/u/HorseloverFat)\ **Post date:** [November 23, 2009, 2:53pm UTC](https://boards.straightdope.com/t/is-it-dangerous-to-open-a-microwave-door-before-the-timer-winds-down/518634/5 "2009-11-23T14:53:33Z")
Even if we removed the off button on the door, it still wouldnt “let out dangerous radiation” or whatever nonsense your friend beileves. Microwaves generate -you guessed it- microwaves that excite water molecules so food gets warm. There’s no mysterious radioactive gas like in some Troma movie. The door is there so you dont get burned, just like your oven door. Dangerous radiation is typically ionizing radiation which is stuff like xrays. You dont own anything that makes dangerous amounts of xrays. ---
**Author:** ![guizot](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/guizot/32/3636_2.png) [@guizot](https://boards.straightdope.com/u/guizot)\ **Post date:** [November 23, 2009, 4:29pm UTC](https://boards.straightdope.com/t/is-it-dangerous-to-open-a-microwave-door-before-the-timer-winds-down/518634/6 "2009-11-23T16:29:55Z")
> [@HorseloverFat](#): > > You dont own anything that makes dangerous amounts of xrays. And what makes you so sure of that? Just you wait and see! ---
**Author:** ![Munch](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/munch/32/5281_2.png) [@Munch](https://boards.straightdope.com/u/Munch)\ **Post date:** [November 23, 2009, 4:41pm UTC](https://boards.straightdope.com/t/is-it-dangerous-to-open-a-microwave-door-before-the-timer-winds-down/518634/7 "2009-11-23T16:41:09Z")
> [@HorseloverFat](#): > > Dangerous radiation is typically ionizing radiation which is stuff like xrays. You dont own anything that makes dangerous amounts of xrays. Well, I do have a basement full of smoke detectors… ---
**Author:** ![beowulff](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/beowulff/32/542_2.png) [@beowulff](https://boards.straightdope.com/u/beowulff)\ **Post date:** [November 23, 2009, 4:45pm UTC](https://boards.straightdope.com/t/is-it-dangerous-to-open-a-microwave-door-before-the-timer-winds-down/518634/8 "2009-11-23T16:45:13Z")
> [@HorseloverFat](#): > > You dont own anything that makes dangerous amounts of xrays. [Maybe, maybe not.](http://www.time.com/time/magazine/article/0,9171,837185,00.html) ---
**Author:** ![Machine\_Elf](https://avatars.discourse-cdn.com/v4/letter/m/82dd89/32.png) [@Machine\_Elf](https://boards.straightdope.com/u/Machine_Elf)\ **Post date:** [November 23, 2009, 5:28pm UTC](https://boards.straightdope.com/t/is-it-dangerous-to-open-a-microwave-door-before-the-timer-winds-down/518634/9 "2009-11-23T17:28:23Z")
> [@beowulff](#): > > [Maybe, maybe not.](http://www.time.com/time/magazine/article/0,9171,837185,00.html) I doubt many people own TV sets from 1967 anymore. ---
**Author:** ![robby](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/robby/32/11048_2.png) [@robby](https://boards.straightdope.com/u/robby)\ **Post date:** [November 23, 2009, 6:43pm UTC](https://boards.straightdope.com/t/is-it-dangerous-to-open-a-microwave-door-before-the-timer-winds-down/518634/10 "2009-11-23T18:43:39Z")
> [@beowulff](#): > > There’s an interlock that turns of the magnetron when the door is opened. If the interlock failed, you could get burned it you opened the door and got exposed to a full blast of microwaves. Still, I trust the interlock and do what you did all the time. True enough, but it was ingrained into me when I was in the Navy that you should **never** depend on an interlock. I always hit the “off” button before opening the microwave door. ---
**Author:** ![johnpost](https://avatars.discourse-cdn.com/v4/letter/j/f17d59/32.png) [@johnpost](https://boards.straightdope.com/u/johnpost)\ **Post date:** [November 23, 2009, 6:52pm UTC](https://boards.straightdope.com/t/is-it-dangerous-to-open-a-microwave-door-before-the-timer-winds-down/518634/11 "2009-11-23T18:52:20Z")
on devices with a mechanical timer the timer will still run after you shut the microwaves off by the off button or the door open button (which shuts off the microwaves if the interlock is working). ---
**Author:** ![Anne\_Neville](https://avatars.discourse-cdn.com/v4/letter/a/b9e5f3/32.png) [@Anne\_Neville](https://boards.straightdope.com/u/Anne_Neville)\ **Post date:** [November 23, 2009, 7:03pm UTC](https://boards.straightdope.com/t/is-it-dangerous-to-open-a-microwave-door-before-the-timer-winds-down/518634/12 "2009-11-23T19:03:25Z")
> [@robby](#): > > True enough, but it was ingrained into me when I was in the Navy that you should **never** depend on an interlock. > > I always hit the “off” button before opening the microwave door. If the interlock did fail, how bad would it be to be hit with microwaves from a typical microwave oven for a few seconds? Presumably, if this happened, you’d notice that the microwave was still on and hit the off button a second or two later. Would it make a difference if you were wearing metal (watch, jewelry, buttons, etc) or not? ---
**Author:** ![johnpost](https://avatars.discourse-cdn.com/v4/letter/j/f17d59/32.png) [@johnpost](https://boards.straightdope.com/u/johnpost)\ **Post date:** [November 23, 2009, 7:05pm UTC](https://boards.straightdope.com/t/is-it-dangerous-to-open-a-microwave-door-before-the-timer-winds-down/518634/13 "2009-11-23T19:05:25Z")
> [@guizot](#): > > Setting aside that every microwave I know of turns itself off when you open its door, could “stray” microwave radiation really cause any harm? the microwaves in the oven cavity no longer exist to stray anywhere before the door opens if the interlock is operating correctly (if the fan, light and carousel motor shut off then so do the microwaves). ---
**Author:** ![johnpost](https://avatars.discourse-cdn.com/v4/letter/j/f17d59/32.png) [@johnpost](https://boards.straightdope.com/u/johnpost)\ **Post date:** [November 23, 2009, 7:09pm UTC](https://boards.straightdope.com/t/is-it-dangerous-to-open-a-microwave-door-before-the-timer-winds-down/518634/14 "2009-11-23T19:09:24Z")
> [@Anne\_Neville](#): > > If the interlock did fail, how bad would it be to be hit with microwaves from a typical microwave oven for a few seconds? Presumably, if this happened, you’d notice that the microwave was still on and hit the off button a second or two later. Would it make a difference if you were wearing metal (watch, jewelry, buttons, etc) or not? for a few seconds it probably wouldn’t matter to your hand. metal wouldn’t change that. people have been exposed to much larger doses accidentally or foolishly without damage as i recall. ---
**Author:** ![beowulff](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/beowulff/32/542_2.png) [@beowulff](https://boards.straightdope.com/u/beowulff)\ **Post date:** [November 23, 2009, 8:46pm UTC](https://boards.straightdope.com/t/is-it-dangerous-to-open-a-microwave-door-before-the-timer-winds-down/518634/15 "2009-11-23T20:46:11Z")
> [@Joe Frickin Friday](#): > > I doubt many people own TV sets from 1967 anymore. You haven’t met my friends… ---
**Author:** ![Anne\_Neville](https://avatars.discourse-cdn.com/v4/letter/a/b9e5f3/32.png) [@Anne\_Neville](https://boards.straightdope.com/u/Anne_Neville)\ **Post date:** [November 23, 2009, 9:00pm UTC](https://boards.straightdope.com/t/is-it-dangerous-to-open-a-microwave-door-before-the-timer-winds-down/518634/16 "2009-11-23T21:00:50Z")
> [@beowulff](#): > > You haven’t met my friends… Or my parents. I don’t actually know how old their TVs are. If they did date back to the 60’s, I wouldn’t be a bit surprised. You think that’s why I don’t need a night light, I can see by my own glow? 😉