Expansion Tank on HWH in Carroll County MD

[Laura Line]

would anyone happen to know the date of when the expansion tank became code in Carroll County Maryland when you install a new Hot water heater?
I have been unable to find the date, HWH was a 2003

thanks for your help
Laura

[James H. Bushart]

You should probably ask the Carroll County, Maryland, Department of Public Works who wrote and enforce that code.