Abstract: A trap bottle assembly for mounting on a suction regulator or controller is disclosed. The trap bottle assembly includes a mounting adaptor for mounting on the suction regulator and a disposable trap bottle for releasable mounting on the mounting adaptor. The mounting adaptor includes a tubular connector and a body member having a peripheral sidewall from which a pair of pins extends. The threaded tubular connector connects the mounting adaptor to the suction regulator or controller. The trap bottle includes an annular flange for tightly engaging an undersurface of the body member to form a good fluid tight interface therebetween. The trap bottle includes a pair of recesses for receipt of the pair of pins, to enable the trap bottle to be releasably secured to the mounting adaptor.