Safety system

A safety system for an ethylene oxide sterilization facility including a plurality of sterilization chambers, each said sterilization chamber having a door for accessing the sterilization chamber, said safety system comprising:

• a locking mechanism connected to the door of each sterilization chamber;
• a chamber sample valve connected to each sterilization chamber;
• a microwave spectrometer adapted to measure the concentration of ethylene oxide in a gas sample taken from any of the sterilization chambers;
• a pump connected to each chamber sample valve and the microwave spectrometer;
• gas communication lines connecting the chamber sample valves, the pump and the microwave spectrometer;
• a central processing unit;
• a timer adapted to measure the length of time which lapses after the locking mechanism of each sterilization chamber is unlocked;
• and
• electric communication lines connecting the central processing unit and each locking mechanism, each chamber sample valve, the microwave spectrometer, the pump and the timer;
• whereby under the control of the central processing unit, the chamber sample valves selectively open to obtain one or more gas samples from the sterilization chambers, the pump directs the gas samples in the gas communication lines to the microwave spectrometer, the microwave spectrometer measures the concentration of ethylene oxide gas in said gas samples, if the concentration of the ethylene oxide gas in said samples is below a predetermined level, the locking mechanism unlocks the door of the sterilization chamber, the timer measures the length of time which lapses after the locking mechanism unlocks the door of the sterilization chamber, and if the door is not opened within a predetermined period of time, the locking mechanism relocks the door of the sterilization chamber.

A safety system for a gas sterilization facility including at least one sterilization chamber, each said sterilization chamber having a door for accessing the sterilization chamber, said safety system comprising:

• means for controlling the safety system;
• means connected to each sterilization chamber for sampling the gas in such sterilization chamber upon command from the control means;
• means for measuring the concentration of a specified gas in the gas sample taken from each sterilization chamber;
• means for directing the gas samples from each sterilization chamber to the gas concentration measuring means;
• means for communicating the concentration of the specified gas to the control means;
• means on each sterilization chamber for locking and unlocking the door on said sterilization chamber;
• and
• means for measuring the length of time which lapses after the locking means of each sterilization chamber is unlocked and for the relocking the locking means of each sterilization chamber if the door is not opened within a predetermined period of time.

A safety system for a gas sterilization facility, said sterilization facility including a plurality of sterilization chambers each having a door for accessing the sterilization chamber, said safety system comprising:

• means for locking the door of each sterilization chamber;
• means for obtaining one or more gas samples from each sterilization chamber;
• means for measuring the concentration of a sterilizing gas in said gas samples obtained from the sterilization chambers;
• means for unlocking the door of the sterilization chamber if the concentration of said sterilizing gas in the said gas samples obtained from said sterilization chamber is below a predetermined level;
• and
• means for re-locking the door of said sterilization chamber after a predetermined period of time if the door of said sterilization chamber is not opened.

A method for preventing access to a gas sterilization chamber in a sterilization facility if there are dangerous levels of a specified sterilization gas in the sterilization chamber, said sterilization chamber having a door for accessing the sterilization chamber and a locking mechanism for locking said door, said method comprising the steps of:

• locking the door of the sterilization chamber;
• completing the sterilization process;
• obtaining a gas sample from the sterilization chamber;
• transferring said gas sample to a gas measuring apparatus;
• determining the concentration of said specified sterilization gas in the gas sample;
• determining if the concentration of the specified sterilization gas in the gas sample is above, at or below a predetermined dangerous level;
• maintaining the door locked if the level of the specified sterilization gas in the gas sample is at or above the predetermined dangerous level;
• unlocking the door if the level of the specified sterilization gas in the gas sample is below the predetermined dangerous level;
• measuring the period of time after the door is unlocked;
• and
• re-locking the door after a predetermined period of time if the door of the sterilization chamber is not opened to prevent access to the sterilization chamber.