Build Habits and Keep Focus.
If the new safety rules are unclear, overly complicated, egregiously restrictive or poorly enforced, employees will spend a lot of mental energy and emotion focusing on how to act or not act in the new environment. They, rightly, may not feel safe and consequently, not valued. This all impacts the quality of work negatively.
A good plan, effectively communicated and enforced goes hand in hand with good work. Prioritize risks and simplify instructions where you can. If wearing masks, maintaining distance and other behavior can be turned into good habits, they become second nature and the decisions to take these steps occur in the background of the mind, freeing it to focus on the task at hand which is the work.