Gym equipment is constantly is not only in contact with - yes - sweaty users, it is meant to be that way! Locker rooms are cross-roads for folks coming from outside with those sweating back from the treadmill and a further group of showered, cleansed and refreshed clients. The air in gyms has that humid, heavy taint.
Fragrances can perfume the air, chemicals can disinfect. But the air remains contaminated, while chemicals can leave residues as well as damage certain materials in many unsuspected ways.
Ozone will create a germ-free environment, whether in the exercise area or the locker room. Air and surfaces get disinfected.
Have a spa or pool area? More benefits are drawn. Surfaces can be cleaned without leaving strong chemical traces. Pool water can be maintained crystal clear without leading to eye-burn, dry and itchy skin nor that lingering smell...