Security access scanners should be on the right
Friction: Most people are right-handed; left-handed users already adapt.
Why this matters
The vast majority of the population is right-handed. Placing scanners on the left causes users to cross their body or twist, slowing down the flow for everyone.
Good Sense principle
Optimize for the majority use case to maintain speed and flow. Consistency matters more than perfection for every individual case (left-handed users are accustomed to adapting, but inconsistent placement confuses everyone).