75:11 One may not put water into the candle holders so that when the candles reach that spot, they will go out. (One may, however, put something like sand in the candle holder to impede burning beyond a certain point – Mishnah Brurah 265:18.) This should not be done even on Friday afternoon, though in a case of need, one may be lenient if the water was added before Shabbos. (One must also be careful to do so before lighting the candles – MB 265:18.) However, it is completely prohibited, even before Shabbos, to place a bowl of water under a chandelier holding candles in order to catch any sparks and extinguish them. (If one did place such a bowl, he must remove it. – Bi’ur Halacha 265:2 s.v. aval. One may be lenient if there is an actual danger of fire, though one should preferably have a minor place the bowl – MB 265:16.) One may place a bowl without water to catch the sparks even on Shabbos. This is permitted because sparks have no substance (and will therefore not render the bowl a base for muktzeh – MB 265:14). One may not place a dish to catch dripping oil once Shabbos has begun because that does affect the dish’s status and renders it halachically immovable on Shabbos. (This would be permissible to avoid a fire that may be cause by falling candles – MB 265:5 – or if the dish previously contained a permitted item and it may then be moved for the sake of that item – MB 265:6.) One may place a dish to catch oil before Shabbos begins, though one may not use this oil on Shabbos, nor may one move the dish. One may move the dish if no oil dripped because the intention alone does not prohibit it.
75:12 It is preferable to place the loaves on the table before lighting the candles.