“Question: Does a cast pose a problem of chatzitzoh for tevila?
Discussion: First of all, when discussing chatzitzos [lit. separation; i.e. any substance that separates between the body and the water], the general rule is that a chatzitzoh is problematic if one is makpid [particular] about its presence or if the substance covers the majority of the body (c.f. Shulchan Aruch YD 198:1).
The precedent to a (plaster) cast can be found in the Shulchan Aruch (YD Siman 198):
• The Shulchan Aruch (s.k. 23) writes that splints that are used to set a broken bone are considered a chatzitoh if they are tightly bound to the limb. However, if they are loose, they do not pose an issue of chatzitzoh [because water can penetrate between the splint and the body and thus there is no issue of chatzitzoh].
Several Acharonim (Beis Hillel; Pischei Teshuva s.k. 13 quoting Rav Doniel) take up issue with the leniency of the Shulchan Aruch regarding loose items, and maintain that even loose items (e.g. rings) pose a problem of chatzitzoh.
• Regarding a “retiyah” [a medicated gauze] the Shulchan Aruch (YD Siman 198 s.k. 10) clearly rules that this is chotzetz.
Plaster casts would certainly be classified as tightly bound, because they do not allow the passage of water between the cast and the skin underneath. Therefore, plaster casts do pose a problem of chatzitoh, and a lady may not tovel with a cast. This is the general consensus of the Poskim (Teshuva Me’ahava YD Siman 198; Chasam Sofer 6:82, Aruch Hashulchan s.k. 29; Rav Wosner – Shi’urei Shevet Halevi Siman 198:10; Rav Nissim Karelitz – Chut Hashoni Hilchos Niddah; Rav Mordechai Gross – Shi’urei Tahara page 399).
It should be mentioned that we do find a minority of Poskim who maintain a lenient position regarding casts. The main precedent for this comes from the Mordechai, quoted by the Remo YD 198:6 that a certain type of hair plait that would pose a danger to life to remove it, is not an issue of chatzitzoh. Most of the lenient opinions (Rav Akiva Eiger – Responsa #60; Divrei Chaim – Responsa volume 2, #65; Levushei Mordechai – Responsa volume 1, #126) are only lenient in a situation where removing the cast would pose a danger to life. Applying this leniency to plaster casts nowadays is far from straightforward. In many cases, plaster casts can be removed for a few hours by a skilled professional to enable tevila and a new cast can be re-applied without any question of danger to limb or life. Therefore, it is not conclusive that these aforementioned Poskim would be lenient, seeing as removal of the cast poses no danger whatsoever.
Another lenient position found is the view of the Avnei Nezer (Responsa volume 1, #253) who posits that if the cast has to remain in place for a minimum of six months then in extenuating circumstances it can be considered a permanent appendage to the body and not a chatzitzoh. The Avnei Nezer presents a revolutionary explanation for this; whatever is classified kesher shel kayomo regarding meleches Shabbos will automatically be termed eino makpid regarding tevila.]
Conclusion: Plaster casts do pose a problem of chatzitzoh and a lady may not be tovel if she has a cast on any area of her body.
Although we do find mention of room for leniency in a minority of the Poskim, it is questionable if the reasons given for the leniency can be applied nowadays.
A question of this nature must be addressed to a competent Rav and can depend on the situation and length of time that the cast must remain in place.
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