ASTM's standard is comparable. The weak ANSI Z90.4 standard is dead. Visors are not tested for shattering or snagging in a fall, so you are on your own there. Comfort Requirements Coolness, ventilation, fit and sweat control are the most critical comfort needs. Air flow over the head determines coolness, and larger front vents provide better air flow.
Most current helmets have adequate cooling for most riders.
Sweat control can require a brow pad or separate sweatband. A snug fit with no pressure points ensures comfort and correct position on the head when you crash. It may take a half hour of wearing to feel pressure points. Weight has not been an issue with today's thin shell helmets. Special Problems Pony tail ports improve fit and cooling for those with long hair.