When it comes to making employees aware of anything important, there are a number of internal channels of communication that can be used. Firstly, you could start a monthly company email newsletter that discusses these issues. This is a great way to communicate, because everybody should be checking their inbox on a daily basis, so emails are hard to miss.
Reminders of all relevant legislation and regulations can be provided using noticeboards around the office building. This may not be quite as effective as emails, because it's easy to pass by a noticeboard without paying attention to what's on it.
The third, and possibly the most effective, way to communicate about these important issues is to hold seminars in which you explain the policies to your staff members in detail. This allows for easy two-way communication, meaning that if somebody doesn't understand something, they can ask about it.
Ensuring compliance with these rules means following disciplinary procedures in cases when they are not adhered to.