Hacham Yishak Beracha, in his book Birhat Yishak on Hilchot Mukse (p.10), establishes a principle based on the Gemara in Masechet Shabbat (p. 124) that any item not considered a Keli (utensil), is completely Mukse, and may not be moved even L'Sorech M'komo-for its place, or L'sorech Gufo-for a permitted function. Therefore, a log of firewood is altogether Mukse and may not be moved for any purpose. A log is not a Keli (utensil), since it only has a one-time use; it is consumed as soon as its purpose is fulfilled.
Hacham Yishak applies this principle to matches, cigarettes and charcoal, as well. These items are not considered a Keli, since they are consumed and destroyed with their use. However, he cites Hacham Bension who distinguished between a natural log of firewood and these items which were designed and produced expressly for this purpose. Therefore, he considers the match a Keli (utensil), and it may be moved L'Sorech M'komo-for its place, or L'sorech Gufo-for a permitted function-such as a toothpick or collar stay. Rav Moshe Feinstein (Russia-New York, 1895-1986) was stringent and did not view matches as a utensil, rather as firewood.
However, all agree that this line of reasoning does not apply to a disposable utensil whose function was prohibited, such as an aluminum foil baking pan. Although like firewood, it too is discarded upon completing its function, there are two major differences. First, while the disposable pan may be thrown away after use, it does not disintegrate as the log, match and cigarette. Moreover, it is common to reuse aluminum foil pans nowadays. Therefore, disposable pans have the same Halacha as cooking pots and are designated Keli She'm'lachto L'isur, which may be moved L'Sorech M'komo-for its place, or L'sorech Gufo-for a permitted function.
SUMMARY
A log of firewood is completely Mukse and may not be moved for any purpose.
Disposable baking pans are utensils and may be moved L'Sorech M'komo-for its place, or L'sorech Gufo-for a permitted function.
One should avoid using matches for a permitted function, such as for a toothpick, although there are those who are lenient.
