Take it from an expert. “When breeze blows over the opening of the vent stack, it creates a sort of vacuum effect. The smells are pulled up the vent stack and out, hopefully keeping them from accumulating in the unit itself. This almost never happens if people do not close the lid,” according to Sam Cooper a quality control engineer of PolyJohn.

Every outdoor toilet based off of George Harding’s 1964 portable toilet cabana patent has a ventilation pipe. In fact, some even have electric fans to improve airflow.

Clean and accessible toilets at venues are nothing to mess with. Coachella wouldn’t agree to provide a giant dome for Kanye West to perform in because it would have required moving a large section of portable toilets, a executives explained to Billboard. West nearly backed out of appearing this year when his demand went unmet.

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