to avoid radio traffic, is it allow to communicate verbally (face to face) in the incident command post with incident commander.
hope to find any code support my question
Wow, talk about taking rules and standards too far. Of course face to face communications is allowed, though let me note that sometimes you need to choose when it's appropriate to directly engage the IC and when it isn't. You cannot have people constantly asking the IC questions. Typically this is not an issue where all the players within the ICP know their roles. I've never seen anything that said all information must be radio "aired", and would find that utterly ridiculous. You need to be able to discuss ideas, problems and details without broadcasting them, and the IC is likely to be directly involved in those discussions.
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