How long does hsv1 survive on plastic surfaces like the outer washing machine? and also metal taps?

a) Maybe a few minutes. b) It doesn't matter. HSV is not transmitted by contact with contaminated surfaces, and not from toilet seats, towels, doorknobs, sinks, eating utensils, etc. If an adult in the house has oral or genital herpes, h/se should take precautions for kissing or sex. Also temporarily avoid close contact with a child with an oral herpes outbreak. Otherwise no risk and no worries.