Mishnah Taharos 8:1: One who lives in the same courtyard as an am ha'aretz [a non-learned person, assumed to be impure], if he [the former] leaves vessels in the courtyard, even if they are barrels with a tight seal, or an oven with a tight seal, these are all impure. Rabbi Yehuda declares the oven pure when it has a tight seal. Rabbi Yose says: even the oven is impure, until he makes a wall around it ten handbreadths high.

הַדָּר עִם עַם הָאָרֶץ בְּחָצֵר, וְשָׁכַח כֵּלִים בֶּחָצֵר, אֲפִלּוּ חָבִיּוֹת מֻקָּפוֹת צָמִיד פָּתִיל, אוֹ תַנּוּר מֻקָּף צָמִיד פָּתִיל, הֲרֵי אֵלּוּ טְמֵאִין. רַבִּי יְהוּדָה מְטַהֵר בְּתַנּוּר בִּזְמַן שֶׁהוּא מֻקָּף צָמִיד פָּתִיל. רַבִּי יוֹסֵי אוֹמֵר, אַף הַתַּנּוּר טָמֵא, עַד שֶׁיַּעֲשֶׂה לוֹ מְחִצָּה גָבוֹהַּ עֲשָׂרָה טְפָחִים:

Mishnah Taharos 8:2: One who leaves vessels in the care of an am ha'aretz, they are [assumed to be] impure with the impurity of a dead body and with midras impurity [a type of impurity due to being sat on by certain types of impure individuals, rendering it an Origin of impurity]. If he [the am ha'aretz] knows that he [the vessels' owner] is one who eats terumah, they are pure from the impurity of a dead body, but they are still impure with midras impurity. Rabbi Yose says: If he gave him a chest full of clothes, if it was brimming they are impure with midras impurity, if it was not brimming [but rather, was loosely packed] they are impure with madaf impurity [a lesser type of impurity which can only render food and liquids impure], even if the key remains with the owner.

הַמַּפְקִיד כֵּלִים אֵצֶל עַם הָאָרֶץ, טְמֵאִים טְמֵא מֵת וּטְמֵאִין מִדְרָס. אִם מַכִּירוֹ שֶׁהוּא אוֹכֵל בַּתְּרוּמָה, טְהוֹרִין מִטְּמֵא מֵת, אֲבָל טְמֵאִין מִדְרָס. רַבִּי יוֹסֵי אוֹמֵר, אִם מָסַר לוֹ תֵבָה מְלֵאָה בְגָדִים, בִּזְמַן שֶׁהִיא רוֹצֶצֶת, טְמֵאִין מִדְרָס. אִם אֵינָהּ רוֹצֶצֶת, טְמֵאִין מַדָּף, אַף עַל פִּי שֶׁהַמַּפְתֵּחַ בְּיַד הַבְּעָלִים: