Karpas and Tumah

An Overview of a Shiur by Rav
Daniel Dumbroff on Parshas
Shemini

(וכי יותן מים על זרע ונפל מנבלתם עליו טמא הוא לכם (ויקרא יא:לח

• Netilas Yadayim for fruit dipped in
  liquid – Chazal required this due to a complex gezeira related to tumah.
• Mishna Berura – Many people do not
  do this today, and although there is some support for that, one should really
  comply with the gezeira.
• If the fruit is less than a
  k’zayis –
  Mishna Berura says
  there is room to be lenient, based on a precedent concerning netilas yadayim
  for bread.
• Pesach Night – Everyone
  washes for karpas
  dipped in salt water to comply with the stringent opinions.
  • Tur –
    Eat less than a kezayis
    of karpas
    to allow the beracha count for the maror but still avoid questions
    about reciting a beracha
    acharona.
  • Mishna Berura:
    • If so, how does this help,
      if no netilas
      yadayim is needed for less than a kezayis?   
    • Response – Ultimately, we
      must agree with the Tur and
      be machmir (even
      if we don’t understand). Therefore, less than a kezayis of fruit or vegetable dipped in liquid also
      renders one chayav.