Buddy Dive in Bonaire will not allow using an Air-2 type combination octo/inflator hose to prevent spreading COVID-19. They have posted new procedures for diving on their website. I have attached a PDF copy. Here's their exact text:
"During Buddy Dive supervised diving activities (boat dives, guided shore dives and courses) guests must be in the possession of an alternate air source. This cannot be the alternate air source and inflator hose combo or “air2’’."
The rationale is when you use an Air-2 to share air, you take your primary regulator out of your mouth and give it to the person needing air. Sharing the regulator could spread the COVID-19 virus.
Buddy Dive also now requires that if you use your alternate air source during a dive, it must be disinfected immediately after the dive. So you can't test your alternate during the pre-dive check by putting it in your mouth and breathing through it. Here's their exact text:
"Alternate air source use during all diving activities will result in a mandatory disinfect rinse of gear immediately after the dive."
Buddy Dive has posted this on their website to give divers advanced notice of their requirements. Other dive operations may have similar requirements that are not publicly posted. If you use an Air-2 type octo/inflator, and are going abroad, you may want to check ahead with their dive operations to see if you can use your regulator there. They may have rentals available.