ASCE-7 live load reduction is specified in code section 4.8. Live load effects on members with influence areas of less than 400 square feet are not modified by live load reduction.

ASCE-7 requires that live loads in excess of 100 psf and live loads from passenger car garages shall not be reduced, except that members supporting two or more floors may be reduced up to 20% per code sections 4.8.2 and 4.8.3. These two load types must be drawn on a "Live (storage)" loading to be considered appropriately.

ASCE-7 requires that live loads of 100 psf or less in public assembly occupancies cannot be reduced per section 4.8.4. These loads must be drawn on a “Live (unreducible)” loading to be considered appropriately

The tributary area of one-way slabs is not limited per section 4.8.5. However, if you limit the design strip width to 1.5 times the span length, and the behavior is that of a one-way slab, then the requirements of this code section will be met.