A manifold for connection to a medical/surgical waste collection unit, the waste collection unit having a receiver for receiving the manifold, said manifold comprising: a housing (158, 164) defining a void space, said housing including: at least one fitting for receiving a suction line that defines a fluid communications path into the void space; a housing base that is the proximal end of the housing; and an outlet opening formed in the housing base, through which fluid can flow from the void space, the outlet opening dimensioned to receive a fitting integral with the receiver, wherein the housing (158, 164), including the housing base, is adapted to be rotated in the receiver; and a drip stop fitted to the housing outlet opening, the drip stop having: a valve (187, 190) disposed over the outlet opening that is normally closed so as to selectively block fluid flow out of the housing outlet opening and is positioned to be actuated by the receiver fitting so that, upon the seating of the fitting in the outlet opening, the fitting opens the value; and a drip stop base with inner surfaces (272, 274, 276); wherein the housing includes a seal (187, 274) that, when the receiver fitting is in the outlet opening, establishes a barrier between the housing and the receiver fitting; characterized in that: the drip stop base is formed to have: a first inner annular surface that tapers inwardly up from the proximal end of the base; a bead extending circumferentially around the interior of the base and, the bead, in cross section, has a convex profile, wherein the first annular surface tapers inwardly towards the bead and the inner diameter of said bead is less than the outer diameter of the receiver fitting, so that the bead functions as the housing seal; and a second inner annular surface that extends upwardly from said bead, said second annular inner surface having a diameter greater than that of said bead, wherein the bead is formed between the first and second inner annular surfaces. a housing (158, 164) defining a void space, said housing including: at least one fitting for receiving a suction line that defines a fluid communications path into the void space; a housing base that is the proximal end of the housing; and an outlet opening formed in the housing base, through which fluid can flow from the void space, the outlet opening dimensioned to receive a fitting integral with the receiver, wherein the housing (158, 164), including the housing base, is adapted to be rotated in the receiver; and a drip stop fitted to the housing outlet opening, the drip stop having: a valve (187, 190) disposed over the outlet opening that is normally closed so as to selectively block fluid flow out of the housing outlet opening and is positioned to be actuated by the receiver fitting so that, upon the seating of the fitting in the outlet opening, the fitting opens the value; and a drip stop base with inner surfaces (272, 274, 276); wherein the housing includes a seal (187, 274) that, when the receiver fitting is in the outlet opening, establishes a barrier between the housing and the receiver fitting; characterized in that: the drip stop base is formed to have: a first inner annular surface that tapers inwardly up from the proximal end of the base; a bead extending circumferentially around the interior of the base and, the bead, in cross section, has a convex profile, wherein the first annular surface tapers inwardly towards the bead and the inner diameter of said bead is less than the outer diameter of the receiver fitting, so that the bead functions as the housing seal; and a second inner annular surface that extends upwardly from said bead, said second annular inner surface having a diameter greater than that of said bead, wherein the bead is formed between the first and second inner annular surfaces. the drip stop base is formed to have: a first inner annular surface that tapers inwardly up from the proximal end of the base; a bead extending circumferentially around the interior of the base and, the bead, in cross section, has a convex profile, wherein the first annular surface tapers inwardly towards the bead and the inner diameter of said bead is less than the outer diameter of the receiver fitting, so that the bead functions as the housing seal; and a second inner annular surface that extends upwardly from said bead, said second annular inner surface having a diameter greater than that of said bead, wherein the bead is formed between the first and second inner annular surfaces.