From what I understand, halacha places a limit on washing hands on Yom Kippur up to knuckles. Does anyone know of a psak which waives this limitation (up to knuckles) and allows a more extensive washing due to Covid-19?
Washing for cleanliness was never included in the prohibition. The command of "afflict yourselves" was against washing for enjoyment. Sorry if there was some confusion about this.
- Washing with soap/cleansing with sanitizer – It is permitted to wash hands to remove dirt (Shulchan Aruch, OC 613:1). Removing germs is no less justified; only washing which can be broadly deemed as for enjoyment is forbidden. In a past column (Vayeilech 5776), we cited sources that sicha (applying oil) is forbidden even not for enjoyment (Yerushalmi, Yoma 8:1). We pointed out that sicha is when the substance is absorbed by the skin, whereas rechitza removes impurities from it, and that soap resembles rechitza. Sanitizer is on one hand, absorbed by the skin, but on the other hand, is never for enjoyment. Certainly, when it is clearly needed for hygiene, including during a pandemic even for healthy people, it is permitted (see Shulchan Aruch, OC 614:1, who permits applying oil for any truly medicinal purpose).
As you assert washing represents one of the 'inuyim' (afflictions) of Yom Kippur - refer to the Mishna in Yoma 73b.
In light of the dangers posed by the pandemic many Rabbonim have paskened the necessity to wash hands and thereby negate the spread of any germs and the like even on Yom Kippur. In this useful document from Ohr Torah Stone here on p.12 (under the auspices of Rav Shlomo Riskin) in light of the virus they advise that in accordance with health guidelines, it is permissible to wash hands with cold water and liquid soap or to use wipes or alcohol.
DUE TO COVID-19, AM I ALLOWED TO WASH MY HANDS ON TISHAH B’AV AND YOM KIPPUR AS NORMAL WITH SOAP ETC.?
During the current pandemic, washing hands is acutely necessary to prevent the spread of the disease. The halochos of Tisha B’Av and Yom kippur allow hand washing with soap and/or sanitizer as is needed to facilitate hygiene. If hands are already clean and being washed due to davening or negel vasser, then they should be washed only to the knuckles.
Thus, one needs to be sensible in light of the virus and any make-safe actions are encouraged. You should speak your local orthodox Rov for greater clarity and guidance.