Why Doesn't Atmospheric Pressure Deflate Basketballs and Footballs?

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International basked ball games are played with a basket ball inflated to 8 PSI. But I am curious to understand how it can stay inflated when the atmospheric pressure is 14.7 PSI.
So shouldn't the external atmospheric pressure overcome the pressure within the ball ? Shouldn't the air pressure within the basket ball be greater than the atmospheric pressure ?
 
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Welcome to PF;
The basketball is inflated to "8PSI gauge" ... which is 22.7PSI absolute.
This is because pressure gauges work off the difference between two pressures and the most handy pressure is the ambient air pressure. This also means that basket balls are at different pressures depending on the weather.
 
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Simon Bridge said:
https://en.wikipedia.org/wiki/Thomas_Brady

Wasn't there something in (American) football about the effects of filling the ball to the wrong pressure or something?
Yes. Big sports story for 2014-2015. Some of the roadies who work for the New England Patriots heard that quarterback Tom Brady thinks it is easier to throw the football in cold weather if it is inflated to a lower pressure. So, for a big play-off game in 2014, they inflated the official game balls to below regulation pressure. The rest is history.

Chet