There are no quota restrictions for O, P and R visas.
O visas: They are available to persons of proven extraordinary ability in the sciences, arts, education, business or athletics. To be considered a person of extraordinary ability, you must have sustained national or international acclaim, or, if you work in motion pictures or television productions, you must have a demonstrated record of extraordinary achievement. O-1 visas can be given on only the basis of individual qualifications. O-2 visas are available to those who work as essential support personnel of O-1 athletes and entertainers. O-2 visas are not available in the fields of science, business or education. O-3 visas are available to accompanying spouses and unmarried children under the age of 21.
P-1 visas: They are available to athletes or athletic teams that have been internationally recognized as outstanding for a long and continuous period of time. Entertainment companies that have been nationally recognized as outstanding for a long time also qualify. Like O-1 visas, P-1 visas are issued only for the time needed to complete a particular event, tour, or season.
P-2 visas: They are available to artists or entertainers, either individually or as part of a group, who come to the U.S. to perform under a reciprocal exchange program between the U.S. and one or more other countries.
P-3 visas: They are available to artists or entertainers who come to the U.S. either individually or as part of a group, to perform, teach, or coach in a program that is considered culturally unique.
P-4 visas: They are issued automatically to the accompanying relatives of any P visa workers. The accompanying relatives are permitted to remain in the U.S., but they cannot work.
R-1 Visas: They are available to persons who has been a member of a legitimate religious denomination for a least two years and has a job in the U.S. to work for an affiliate of that same religious organization. R-1 visas may be issued to both members of the clergy and lay religious workers. Accompanying relatives of R-1 visa holders can automatically get R-2 visas. This allows them to stay in the U.S., but not work. R visas are limited to a total of five years.