GB894854A - Improvements relating to the sterilization of hypodermic syringes - Google Patents

Abstract

894,854. Sterilizing particles and containers therefor. EVERETT & CO. Ltd., S. & R. J. Jan. 29, 1960 [Jan. 30, 1959; Feb. 19, 1959], Nos. 3423/59 and 5780/59. Class 81 (1). [Also in Group XVII] A method of sterilizing an article, e.g. a hypodermic syringe, by means of dry heat is characterized in that in order to prevent the escape of air during heating, and the consequent entry of unsterile air on cooling, the article to be sterilized is enclosed within a cylindrical container which is just large enough to receive the article, the container being closed at one end by a sealed lid and the body of the container having no other opening. As shown, a rigid container intended for the sterilization and subsequent storage of a hypodermic syringe is in the form of a cylindrical can with a lid 4 having a deep flange 5 which in conjunction with a ring of silicone rubber 6 of 0-section located in a groove effects an air-tight seal. A clip 10 engages the bottom 11 and top 12 of the can to counteract increased pressure in the can. In a modification shown in Fig. 3 there is provided a flexible diaphragm 15 of silicone rubber fitted between the end of the cap 4 and an outer cover 16 such that under the influence of internal pressure the diaphragm 15 is forced outwardly to form a visible bulge, the absence of which indicates leakage. When the assembly cools again, the diaphragm should return to its initial position as shown in Fig. 3 but if there has been any leakage, it will not return fully and the leakage is thus further indicated. According to Provisional Specification a preliminary pressurization of the container may be effected before sterilization takes place by introducing a measured quantity of ether before the vessel is sealed which causes the diaphragm to bulge slightly and during sterilization the convexity of the bulge increases then on cooling returns to its initial shape, any decrease in the degree of bulge indicating a leakage. According to Provisional Specification the addition of a small amount of sterilizing gas such as ethylene oxide enables considerably lower temperatures to be used for sterilization.