Here's an example of a sports federation, the Ontario Equestrian Federation, providing detailed guidance and a new concussion/accident and return to play protocol that came into effect as of January 1, 2017...
http://horse.on.ca/wp-content/uploads/2017/05/2017_OEF_Concussion_Guide.pdf
http://horse.on.ca/wp-content/uploads/2017/05/2017_OEF_Concussion_Guide.pdf