I'm estimating Mark King's hourly rate to be around $50, considering his role as a Snooker referee, which is not a traditional profession with high earning potential. Refereeing is a specialized role, and his skills in Fire Safety, Food Safety, and Customer Service, although relevant, don't necessarily translate to high-paying work. The WPBSA is a small organization, and referees are likely not paid a high hourly rate. A common rate for referees in general is around $25-$50 per hour, depending on the sport and level of experience. Given Mark's 7+ years of experience, I'm on the higher end of this range, but still a relatively modest estimate.