# Why are some farts silent? **URL:** \ **Category:** Factual Questions\ **Created:** [January 23, 2003, 6:53pm UTC](https://boards.straightdope.com/t/why-are-some-farts-silent/150502 "2003-01-23T18:53:47Z")\ **Posts on this page:** 11\ **Page:** 1
**Author:** ![Muad\_Dib](https://avatars.discourse-cdn.com/v4/letter/m/35a633/32.png) [@Muad\_Dib](https://boards.straightdope.com/u/Muad_Dib)\ **Post date:** [January 23, 2003, 6:53pm UTC](https://boards.straightdope.com/t/why-are-some-farts-silent/150502/1 "2003-01-23T18:53:47Z")
Is there a difference between “noisy” and “silent” farts? In all seriousness, what is the difference between them? Is it random? Is it chemical? Is it physical? What causes it? ---
**Author:** ![Q.E.D](https://avatars.discourse-cdn.com/v4/letter/q/51bf81/32.png) [@Q.E.D](https://boards.straightdope.com/u/Q.E.D)\ **Post date:** [January 23, 2003, 6:59pm UTC](https://boards.straightdope.com/t/why-are-some-farts-silent/150502/2 "2003-01-23T18:59:23Z")
Mostly it has to do with two factors: the tightness of the anal sphincter and the pressure of the gas behind it. The tighter the sphincter, and the higher the gas pressure, the noiser the flatulence. If anyone else cares to speculate on the factors that affect sphincter tightness, feel free. This is as far as I go! 😃 ---
**Author:** ![Bearflag70](https://avatars.discourse-cdn.com/v4/letter/b/8e7dd6/32.png) [@Bearflag70](https://boards.straightdope.com/u/Bearflag70)\ **Post date:** [January 23, 2003, 7:01pm UTC](https://boards.straightdope.com/t/why-are-some-farts-silent/150502/3 "2003-01-23T19:01:57Z")
I agree. If you blow air slowly into a trumpet without puckering your lips, the air wil just flow through without “trumpeting”. If you pucker up and increase the air pressure, you will get sound. ---
**Author:** ![MSU\_1978](https://avatars.discourse-cdn.com/v4/letter/m/ac8455/32.png) [@MSU\_1978](https://boards.straightdope.com/u/MSU_1978)\ **Post date:** [January 23, 2003, 7:46pm UTC](https://boards.straightdope.com/t/why-are-some-farts-silent/150502/4 "2003-01-23T19:46:07Z")
Why is it that dog farts never make noise? ---
**Author:** ![lieu](https://avatars.discourse-cdn.com/v4/letter/l/c2a13f/32.png) [@lieu](https://boards.straightdope.com/u/lieu)\ **Post date:** [January 23, 2003, 7:54pm UTC](https://boards.straightdope.com/t/why-are-some-farts-silent/150502/5 "2003-01-23T19:54:51Z")
I agree that [flappage](http://boards.straightdope.com/sdmb/showthread.php?threadid=143292&highlight=talking+out+your) is key to the equation. Maybe dogs can’t hold farts in very well and they never have to chance to build up enough pressure to do the anuslap. ---
**Author:** ![CrankyAsAnOldMan](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/crankyasanoldman/32/11670_2.png) [@CrankyAsAnOldMan](https://boards.straightdope.com/u/CrankyAsAnOldMan)\ **Post date:** [January 23, 2003, 8:15pm UTC](https://boards.straightdope.com/t/why-are-some-farts-silent/150502/6 "2003-01-23T20:15:31Z")
My basset hound sometimes farts going up the stairs, and the farts literally squeak out. So I can’t say dog farts “never” make noise. ---
**Author:** ![RichLather](https://avatars.discourse-cdn.com/v4/letter/r/da6949/32.png) [@RichLather](https://boards.straightdope.com/u/RichLather)\ **Post date:** [January 23, 2003, 8:34pm UTC](https://boards.straightdope.com/t/why-are-some-farts-silent/150502/7 "2003-01-23T20:34:54Z")
I can’t believe I’m contributing to this… My dog’s flatulence varies as much as mine does. Sometimes silent, sometimes not. But what’s fun is to call her on it and watch her get embarrassed (anthropomorphizing, but there _is_ that kind of reaction). ---
**Author:** ![80sHairMetalMaven](https://avatars.discourse-cdn.com/v4/letter/8/ed655f/32.png) [@80sHairMetalMaven](https://boards.straightdope.com/u/80sHairMetalMaven)\ **Post date:** [January 23, 2003, 8:40pm UTC](https://boards.straightdope.com/t/why-are-some-farts-silent/150502/8 "2003-01-23T20:40:32Z")
ROTFLMAO\*😃 IDBB(who just finished reading the other fart thread and is still crying with joy and lusty fartations\* ---
**Author:** ![rookie523](https://avatars.discourse-cdn.com/v4/letter/r/71c47a/32.png) [@rookie523](https://boards.straightdope.com/u/rookie523)\ **Post date:** [January 23, 2003, 8:56pm UTC](https://boards.straightdope.com/t/why-are-some-farts-silent/150502/9 "2003-01-23T20:56:54Z")
my dog farts loud sometimes. not as loud as a human but audible. ---
**Author:** ![Ivar](https://avatars.discourse-cdn.com/v4/letter/i/51bf81/32.png) [@Ivar](https://boards.straightdope.com/u/Ivar)\ **Post date:** [January 23, 2003, 9:11pm UTC](https://boards.straightdope.com/t/why-are-some-farts-silent/150502/10 "2003-01-23T21:11:50Z")
> [@](#): > > \*Originally posted by rookie523 \* > \*\*my dog farts loud sometimes. not as loud as a human but audible. \*\* You haven’t heard my Great Dane! Rattles the windows sometimes… Ok, we’ll quit with the hijack. ---
**Author:** ![handy](https://avatars.discourse-cdn.com/v4/letter/h/b5a626/32.png) [@handy](https://boards.straightdope.com/u/handy)\ **Post date:** [January 23, 2003, 11:56pm UTC](https://boards.straightdope.com/t/why-are-some-farts-silent/150502/11 "2003-01-23T23:56:48Z")
All farts are silent if you’re Deaf. However, the reason they stink is so that the Deaf can enjoy them too.