These requirements apply to factory built residential portable spas that are used for bathing and are operated by private owner. This standard is meant to establish minimum energy efficiency requirements for spas. This standard shall be met notwithstanding certain variations in equipment, materials, and design (Refer to ANSI/NSPI-6). These requirements do not apply to public spas, permanently installed residential spas or other spas, such as those operated for medical treatment, physical therapy or other purposes. Swim-spas and portions of combination spas/swim-spas are included in this standard.