[Racefan]

Fans can be muffled. You build a box around the fan with only the intake and exhaust lines run out. You install a small PC fan to circulate air around the bigger fan if they get too hot. Since most exhaust fans don't run 24/7 it's usually not neccessary for the PC fan. Air cooled lights don't require a lot of air movement for cooling so a smaller quieter fan can be used for them. Most fans are not rated for high heat plus if it's possible use the fan to push air through a area (like a light) rather than pull the air. The fan will be much more efficient that way and last longer.