# How does a gas pump know to shut itself off? By Cecil Adams May 29, 1981

**URL:** <https://boards.straightdope.com/t/how-does-a-gas-pump-know-to-shut-itself-off-by-cecil-adams-may-29-1981/922687>\
**Category:** Miscellaneous and Personal Stuff I Must Share\
**Created:** [October 11, 2020, 3:32am UTC](https://boards.straightdope.com/t/how-does-a-gas-pump-know-to-shut-itself-off-by-cecil-adams-may-29-1981/922687 "2020-10-11T03:32:55Z")\
**Posts on this page:** 2\
**Page:** 1

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**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:** [October 11, 2020, 3:32am UTC](https://boards.straightdope.com/t/how-does-a-gas-pump-know-to-shut-itself-off-by-cecil-adams-may-29-1981/922687/1 "2020-10-11T03:32:55Z")

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> **[How does a gas pump know to shut itself off?](https://www.straightdope.com/21341412/how-does-a-gas-pump-know-to-shut-itself-off)**

From 1981? Some of you might think this is a zombie thread. But no, it is currently being discussed in Hacker News:

> **[How does a gas pump know to shut itself off? (1981)](https://news.ycombinator.com/item?id=24741029)**
>
> 384 points —
> 390 comments —
> tosh —
> 6:57 PM - 10 Oct 2020

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**Author:** ![Elmer\_J.Fudd](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/elmer_j.fudd/32/1211_2.png) [@Elmer\_J.Fudd](https://boards.straightdope.com/u/Elmer_J.Fudd)\
**Post date:** [October 12, 2020, 12:48pm UTC](https://boards.straightdope.com/t/how-does-a-gas-pump-know-to-shut-itself-off-by-cecil-adams-may-29-1981/922687/2 "2020-10-12T12:48:06Z")

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I read that article twice and I think the short answer is “magic”.