Pre-Employment Colorblind Test

Hi all,
My boyfriend has a pre-employment colorblind test next week at a large Trauma center on the East Coast. He's never been officially diagnosed as colorblind but finds it hard to differentiate between different shades of the colors. When I went through this process (same hospital) I had to do the dot test where you have to identify the number in the middle of the circle of dots. He's worried that he might fail and concomitantly be denied employment. I couldn't imagine that happening - he obviously has no problem driving (red/green lights) and quite successfully made it through nursing school with no issues.

Have any of you all had experience with these pre-employment tests? If you are color blind, have you found that hospitals still take you on?

Many thanks for the replies - I'm hoping I can reassure him a bit from them!