A thought for you.
Construction has the highest death rate of any industry, despite the now mountainous documentation/planning/risk assessment/method statement culture that is needed (apparently). Individual companies have brought in testing, but at the limits for driving on the roads.
The rail industry and aviation have zero tolerance, AND have lower limits. Fearfully low. The penalties for failing tests are set by the individual companies in their policies, but are usually instant dismissal for gross negligence. They also have random D&A testing that is conducted by third party organisations, and these are regular and frequent.
For the warehouse manager, I would suggest that if they did a proper risk assessment it would be a no brainer. D&A testing would be introduced on Elfin Safety grounds. However the Senior Decision Making Management are the ones that are most likely to have their work capability affected by alcohol, so they should be included from a business efficiency viewpoint. Imagine the ramifications from bidding too low on a multi million contract due to inebriated desperation/ fatigue.