In house disability policy regarding continuation of health & dental while on disability

We are considering creating a policy to limit the period of time that someone will continue to have health & dental coverage while they are on short or long-term disability. 
As an example, if someone were employed for 3 months to 5 years, we would continue health & dental for 6 months.  If they were employed for 6 months to 10 years, we would continue health & dental for 12 months. etc….
Would a policy like this violate any Alberta labour standards?