Notably on the list are energy infrastructure workers. Those categories are available at the link below. Note that this information is for guidance only to state and local governments, and does not override or supersede lower-level governments' mandates.

This may be useful in your communications with state/local authorities about the status of your projects or operations. We anticipate these recommendations will be taken into account as more state/local governments consider their approaches to restricting industrial and commercial activities to limit the spread of the virus.

The full CISA guidance memo is available here.