The WPRichSnippets plugin supports working/opening hours markups for Rich Snippets. The Hours tab allows you to define sets of Opening Hours via an easy to use drag and drop interface. You can sort fields too if needed.
This functionality works for specific Rich Snippets types, for example Local Business, Restaurants…etc.
Here is an example of open hours schema for Organization:
- Readers Rating
- Rated 4.8 stars
4.8 / 5 (Reviewers)
- Your Rating