The specifications in this standard apply to (a) walk-behind power snow throwers@ (b) ride-on power snow throwers@ (c) lawn ride-on tractors with snow thrower attachments@ (d) lawn and garden tractors with snow thrower attachments@ and (e) lever-steer ride-on machines with snow thrower attachments. These specifications are not intended to apply to hand-held snow throwers nor to airport@ highway@ and agricultural types of snow removal machines and equipment. This standard does not cover all of the specifications that apply to electrically-powered snow throwers. The effective implementation date of this standard shall be two (2) years after the publication date and shall apply to all products built after that date. Manufacturers may also comply with the requirements of this standard anytime after the publication date.