Reference for Kelim 5:2
כִּירָה, תְּחִלָּתָהּ שָׁלֹשׁ, וּשְׁיָרֶיהָ שָׁלֹשׁ, מִשֶּׁתִּגָּמֵר מְלַאכְתָּהּ. אֵיזֶהוּ גְמַר מְלַאכְתָּהּ, מִשֶּׁיַּסִּיקֶנָּה, כְּדֵי לְבַשֵּׁל עָלֶיהָ בֵיצָה קַלָּה שֶׁבַּבֵּיצִים, טְרוּפָה וּנְתוּנָה בְאִלְפָּס. הַכֻּפָּח, עֲשָׂאוֹ לַאֲפִיָּה, שִׁעוּרוֹ כַּתַּנּוּר. עֲשָׂאוֹ לְבִשּׁוּל, שִׁעוּרוֹ כַּכִּירָה. הָאֶבֶן הַיּוֹצֵא מִן הַתַּנּוּר טֶפַח, וּמִן הַכִּירָה שָׁלֹשׁ אֶצְבָּעוֹת, חִבּוּר. הַיּוֹצֵא מִן הַכֻּפָּח, עֲשָׂאוֹ לַאֲפִיָּה, שִׁעוּרוֹ כַּתַּנּוּר. עֲשָׂאוֹ לְבִשּׁוּל, שִׁעוּרוֹ כַּכִּירָה. אָמַר רַבִּי יְהוּדָה, לֹא אָמְרוּ טֶפַח, אֶלָּא בֵין הַתַּנּוּר וְלַכֹּתֶל. הָיוּ שְׁנֵי תַנּוּרִין סְמוּכִים זֶה לָזֶה, נוֹתֵן לָזֶה טֶפַח וְלָזֶה טֶפַח, וְהַשְּׁאָר טָהוֹר:
A stove's minimum size [to become ritually impure] is three [<em>tefachim</em> in height] and its remainder [that remains impure when it is broken] is three [<em>tefachim</em>, once its manufacture is complete. What is the completion of its manufacture? When it is kindled enough to cook the easiest-cooking of eggs on it, scrambled and placed in a pot. A <em>kupach</em> [small stove or brazier] that is made to bake has the same measurement requirements as an oven. If it was made to cook, its measurement requirements are that of a stove. A stone that protrudes a <em>tefach</em> from the oven or a distance of three fingers from a stove is connected. If it protrudes from a <em>kupach</em> made for baking, the measurement is that of the oven. If from a <em>kupach</em> made to cook, its measurement is that of a stove. Rabbi Yehudah says, they did not say tefach except [when the protrusion is] between the oven and the wall. If there were two ovens next to each other, give each one a <em>tefach</em> and the rest is pure.