I asked a Guy that does product approvals and these appliances over 12 amps should have a sticker that states for household use or domestic use. TWH provided the clue the reduced wire size is like the #8 for a range at or under 12 KW being allowed to use an 8 kw demand in domestic use.
Most commercial appliances have no demand factor and I should expect a 20 amp t-slot plug if rated for continuous duty.
