"A picture is worth a thousand words."
I created the following graph to show the information in hours.
The shortest average wait time is just under 2 hours (I see you North Dakota!), or less than 25% of a person's workday (assuming an 8-hour schedule). Maryland (the lone state in bright red) took the top spot at 228 minutes - that's 3.8 hours or nearly half of an individual's workday (again assuming an 8-hour schedule) spent WAITING to be seen by an ER doctor!
If we did a simple calculation to determine the national average (an average of an average in this case), we'd get an average wait time of 2.4 hours. To put that into perspective, the average one-way commute in the United States is just under 28 minutes according to the most recent study by the U.S. Census Bureau.
NEVER go into the ER for minor, non-emergent issues! It's a waste of money and time - yours and your employer's! Until someone figures out time travel, time (unlike money) can never be recovered.
And, for goodness sake, don’t fall for those "10 minute ER wait time" highway signs!