Disposable Cup for Washing Hands?

Ask the Rov: Can I use a disposable cup for netilas yadayim?

By Rabbi Chaim Hillel Raskin – Rov of Anash in Petach Tikvah

When washing for bread, you must wash from a keli (container) just as the kohanim sanctified their hands and feet from the kiyor.¹ The keli used for washing must hold at least a revi’is (2.9 fl. oz.) and be complete without any hole or crack through which liquid could leak. Even if the keli can still hold a revi’is below the crack, it is nevertheless disqualified since the washing water runs over the upper section, which isn’t a valid keli.

If you use a pitcher for netilas yadayim and the spout rises above the rest of the pitcher, you should not pour the water out of the spout, as this higher part cannot hold water, and therefore isn’t considered part of the keli. Instead, pour from the lowest edge of the pitcher’s lip. If the spout is lower, then you must pour from the spout.²

At events, there are often large water containers with faucets at their bottom. The faucet doesn’t disqualify its keli status since it was designed to hold water with the faucet closed. Therefore, if no kvort is available, one may wash by opening and closing the faucet over one’s hands for each pour.³

Many poskim permit using a disposable cup for washing and consider it a keli since it can theoretically be reusable, as long as it isn’t cracked or punctured, and it’s only thrown out after one use due to its cheap price.⁴ However, others question its keli status,⁵ and therefore one should use a more permanent utensil if it is available, or at least intend to keep this specific cup for multiple uses.⁶

If one washed and afterward realized the keli he used was invalid, he must wash again with a bracha.⁷

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From The Weekly Farbrengen by Merkaz Anash