Yes, but you need to understand what that really means and it depends on what the 55cal/cm2 rating is, EBT or ATPV. In a nutshell a 55cal/cm2 ATPV rating means there is a 50% chance you would recieve 2nd degree burns of exposed skin under the suit at a 55cal/cm2 incident energy.
I don't know about the bare skin. Almost every PPE outfit I have seen mentions being worn over cotton underwear (e.g. t-shirt). As Zog said, you do need to know the value the 55cal/cm? number actually represents.