Method For Managing Access To A Confined Space With Renewal Of The Atmosphere By Means Of Forced Ventilation/Extraction And The Use Of Physical Barriers That Can Be Opened In A Variable And Controlled Manner

Abstract

A method for managing access to a confined space which is cooled by the direct injection of a cryogenic fluid, comprising at least one system for closing the confined space, which can prevent access to said confined space and can be opened/closed to a variable and controllable degree, and a data acquisition and processing device. The device can: control the open or closed state of the closure system; set and control the degree to which the closure system is open/closed; ensure that a time delay (TP) is respected every time the closure system is closed, after which time delay the injection of cryogenic fluid into the space resumes; and, at the request of a user, implement the cycle for opening the closure system. The device determines the time that has elapsed (TE) in the closed position since the last closure cycle of the closure system and compares TE to TP. If TE=TP the device immediately authorizes the opening of the closure system. If TE>TP the device authorizes the opening of the closure system after a predefined waiting time.

1 - 3 . (canceled) 
     
     
         4 . A method for managing access to a confined space which is cooled by direct injection of a cryogenic fluid, comprising the steps of:
 closing the confined space with at least one closure system, said at least one closure system being capable of denying access to the confined space;   controlling the opening or closing of said at least one closure system with a data acquisition and processing device, the data acquisition and processing device being capable of:
 controlling whether the said closure system is open or closed, and 
 ensuring, after each closure of said closure system, that a timed period (TP) is observed; 
   at the end of said timed period (TP), injection of cryogenic fluid into the space is recommenced; and   at the demand of a user, instigating a next cycle of opening said closure system wherein:
 the data acquisition and processing device evaluates a time elapsed (TE) since the confined space was last closed; 
 if TE≦TP, opening of said at least one closure system is immediately authorized by the data acquisition and processing device, and 
 if TE>TP opening of said at least one closure system is authorized by the data acquisition and processing device after a predefined waiting time. 
   
     
     
         5 . The method of  claim 4 , wherein:
 said at least one closure system has a degree of opening/closure which is variable and controllable; and   said data acquisition and processing device is capable:   of checking whether said at least one closure system is open or closed, and   of fixing and controlling the degree of opening/closing of said at least one closure system.   
     
     
         6 . The method of  claim 5 , wherein, at the demand of the user, the data acquisition and processing device instigates the following cycle:
 closure of valves that inject refrigerant into the confined space;   partial opening of said at least one closure system;   starting a renewal of the atmosphere in the space by switching on a fan(s) and/or an extractor(s) during said predefined waiting time; and   at the end of said predefined waiting time, the transmission, destined for the user, of an item of information indicating that access to the space is now authorized.   
     
     
         7 . The method of  claim 6 , wherein the item of information is of the visual or audible type,