Text messages are covered, actually. When you make an access-to-information request, text messages from business phones provided by the institution to its officials are definitely covered. The only problem is that it's much more difficult to save these documents. It depends on the institution's computer system.
We don't encourage the use of texting and chatting for work at all. However, if people do use them, we believe it's imperative that they take steps to retain work-related information of importance to government.
There is currently no legal obligation to do so. They are simply guidelines. Establishing this legal obligation is another one of my recommendations.