Every seller of spas, pools and tubs under RCW 70.90.110(1) (a) and (c) shall furnish to the purchaser a complete set of operating instructions which shall include detailed instructions on the safe use of the spa, pool, or tub and for the proper treatment of water to reduce health risks to the purchaser. Included in the instructions shall be information about the health effects of hot water and a specific caution and explanation of the health effects of hot water on pregnant women.