So long as the pipes, hoses, and fittings were all freestanding and not held in the hand, it could be used to fill a mikvah receptacle that met all other requirements.There are also classical requirements for the manner in which the water can be stored and transported to the pool; the water must flow naturally to the mikveh from the source, which essentially means that it must be supplied by gravity or a natural pressure gradient, and the water cannot be pumped there by hand or carried.
A second method is to create a mikveh in a deep pool, place a floor with holes over that and then fill the upper pool with tap water.
In this way, it is considered as if the person dipping is actually "in" the pool of rain water.
In accordance with Orthodox rules concerning modesty, men and women are required to immerse in separate mikveh facilities in separate locations, or to use the mikveh at different designated times.
Converts to Orthodox Judaism, regardless of gender, are also required to immerse in a mikveh.
Most contemporary mikvoth are indoor constructions, involving rainwater collected from a cistern, and passed through a duct by gravity into an ordinary bathing pool; the mikveh can be heated, taking into account certain rules, often resulting in an environment not unlike a spa.
Traditionally, the mikveh was used by both men and women to regain ritual purity after various events, according to regulations laid down in the Torah and in classical rabbinical literature.
In Orthodox Judaism, these regulations are steadfastly adhered to and, consequently, the mikveh is central to an Orthodox Jewish community; they formally hold in Conservative Judaism as well.
The existence of a mikveh is considered so important that a Jewish community is required to construct a mikveh even before building a synagogue, and must go to the extreme of selling Torah scrolls or even a synagogue if necessary, to provide funding for its construction.
Converts to Judaism are required to undergo full immersion in water.