Mishnah Oholot 15:6: A house which is full of straw and there is no handbreadth's space between it and the beams, if there is impurity inside, vessels opposite the exit are impure. If there was impurity outside, vessels inside, if there is in their space a handbreadth by a handbreadth by a height of a handbreadth, they are pure, but if not they are impure. If there was between the straw and the beams a handbreadth's space, in either case they would be impure.

בַּיִת שֶׁהוּא מָלֵא תֶבֶן וְאֵין בֵּינוֹ לְבֵין הַקּוֹרוֹת פּוֹתֵחַ טֶפַח, טֻמְאָה בִפְנִים, כֵּלִים שֶׁכְּנֶגֶד יְצִיאָה טְמֵאִים. טֻמְאָה בַחוּץ, כֵּלִים שֶׁבִּפְנִים, אִם יֵשׁ בִּמְקוֹמָם טֶפַח עַל טֶפַח עַל רוּם טֶפַח, טְהוֹרִים. וְאִם לָאו, טְמֵאִים. אִם יֵשׁ בֵּין תֶּבֶן לַקּוֹרוֹת פּוֹתֵחַ טֶפַח, בֵּין כָּךְ וּבֵין כָּךְ טְמֵאִים:

Mishnah Oholot 15:7: A house that was filled with dirt or pebbles, and was nullified, and similarly a pile of grain or a mound of pebbles, even as large as the mound of Akhan, and even if there was impurity next to the vessels, the impurity pierces and goes up, pierces and goes down.

בַּיִת שֶׁמִּלְאוֹ עָפָר אוֹ צְרוֹרוֹת, וּבִטְּלוֹ, וְכֵן כְּרִי שֶׁל תְּבוּאָה, אוֹ גַל שֶׁל צְרוֹרוֹת, אֲפִלּוּ כְגַלּוֹ שֶׁל עָכָן, וַאֲפִלּוּ טֻמְאָה בְצַד הַכֵּלִים, טֻמְאָה בוֹקַעַת וְעוֹלָה, בּוֹקַעַת וְיוֹרָדֶת: