CodeCuriosity

Intel has a set of guidelines available (publically) that are quite good. It breaks down into three key sections,

When You Engage

Stick to areas that you are an expert in.

Be respectful to the topic and others

Be thoughtful about what you post

Don’t disclose proprietary or confidential information

Be polite, especially when disagreeing with someone

Moderation Guidelines

Breaks down different content sections and rules for each.

Rules of Engagement

This is the most interesting and meaty section of the document. I recommend reading it directly.