A Swimming pool service technicians (known colloquially as "pool men") is a tradesperson that cleans Swimming pool pools and service major pool equipment such as pumps, motors, and filters. Within the swimming pool and spa industry, these tradesman are also known as "pool and spa service professionals" and have two national trade associations that offer membership, IPSSA, the International Pool and Service Association and UPA, the United Pool Association. But, there are as many as 15,000,000 residential pools and spas in the United States and about 400,000 "commercial" or "public" swimming pools according to P.K. Data which is the Georgia-based research firm retained by the pool and spa industry's international trade organization, the Association of Pool & Spa Professionals (APSP). The two service industry trade organizations boast of having about 15,000 members, tops which means that each such professional who is a member would have 1,000 pools each to clean.