Nev. Rev. Stat. § 613.380
Notwithstanding any other provision of NRS 613.310 to 613.435, inclusive, or 613.4383, it is not an unlawful employment practice for an employer to apply different standards of compensation, or different terms, conditions or privileges of employment pursuant to a bona fide seniority or merit system, or a system which measures earnings by quantity or quality of production or to employees who work in different locations, if those differences are not the result of an intention to discriminate because of race, color, religion, sex, sexual orientation, gender identity or expression, age, disability or national origin, nor is it an unlawful employment practice for an employer to give and to act upon the results of any professionally developed ability test, if the test, its administration or action upon the results is not designed, intended or used to discriminate because of race, color, religion, sex, sexual orientation, gender identity or expression, age, disability or national origin.
NRS 613.380