RU2616546C1 - Method of providing fire safe hermetic inhabit objects, mainly submarines, in off line mode - Google Patents

Abstract

FIELD: fire safety.

SUBSTANCE: within each closed space of sealed object, the hypoxic gas environment is built with established initial oxygen reduced at normal pressure gas environment, wherein the oxygen content is adjusted depending on the type of the sealed space due to residence time and the intensity of the crew members therein, at the level providing preventing the occurrence and development of a fire, and the argon concentration is raised to the level of about 27-35 ov. %, wherein the argon concentration is increased at the same time on all the time autonomous navigation.

EFFECT: increased fire safety of submarines and other sealed inhabited objects by creating them hypoxic gas medium with a high content of argon, reduces the likelihood of ignition and fire due to reduced content of oxygen, while creating the conditions for normal life of the submarine crew in a long hike.

5 cl

Description

The invention relates to the field of fire safety of submarines and other pressurized inhabited objects, including protected command posts, aircraft cabins, industrial laboratory and storage facilities, etc., which are in stand-alone mode.

Improving the fire safety of submarines (hereinafter - PL) and other sealed inhabited objects is an urgent scientific and technical task, the solution of which can reduce the risk of death of people and equipment.

In recent years, the possibility of using gas-air media on submarines that reduce the likelihood of fire and fire due to the low oxygen content in them, i.e. the creation of hypoxic gas-air environments (hereinafter - GGVS).

There is a method of creating conditions for human life in a pressure chamber according to the patent of the Russian Federation No. 2138421, IPC B63C 11/00, B63C 11/36, publ. 09/27/1999, According to the method for increasing the fire safety of submarines, it is proposed to use an oxygen-nitrogen medium with an oxygen content of 14 ± 1 vol. % and maintaining an increased pressure of the air so that the partial pressure of oxygen in the medium corresponded to normoxic and amounted to 20-21 kPa, which is necessary to prevent the hypoxic state of crew members.

This method is not safe for the ship and the personnel as a whole. The air pressure on the submarine during the implementation of this method will correspond to 150 kPa, that is, almost 1.5 times higher than normal atmospheric pressure. This leads to a high likelihood of pressure increase in the pressurized room of the submarine above the level acceptable for ship equipment, which is from 1.3 to 1.6 normal for basic equipment. For example, for a turbine, the maximum working pressure is 1.4 normal, and for an air regeneration system, 1.3.

Also necessary when implementing this method is the decompression of the crew after a period of autonomous navigation, which for modern submarines is from 60 to 90 days.

Also known is a hypoxic fire suppression and fire prevention system according to the Norwegian patent No. 20024955 (Α), IPC A62C 2/00; A62C 3/00; A62C 99/00; A62D 1/00; A62D 1/02; B01D 53/02, publ. December 5, 2002, according to which it is proposed to use for all sealed inhabited objects, including submarines, a fire prevention and elimination system at standard atmospheric pressure, in which a fire-extinguishing composition of a mixture of nitrogen and oxygen with an oxygen content of 12 to 17 vol. % with the possible addition of carbon dioxide. When implementing this method for sealed submarines when applying a mixture of nitrogen and oxygen with a percentage of oxygen from 12 vol. % in the PL will be a decrease in oxygen concentration to values that impede combustion. However, at the same time the pressure will increase above the permissible level for ship equipment, and for the health and working capacity of the crew, an increase in pressure can also have a negative effect. So, to achieve an oxygen concentration in the air of 14 vol. %, at which self-sustaining combustion of most of the main ship materials, which are potential sources of ignition and fire spreading on the submarine, is impossible, it will be necessary to increase the pressure in the sealed room 2.3 times to 232 kPa. The crew after working in these conditions during autonomous navigation will require a long decompression. In addition, the proposed method does not establish acceptable time limits for the stay of the crew in the created conditions without damage to health.

Closest to the technical nature of the claimed is a method of preventing fires inside sealed habitable objects, mainly submarines, according to the patent of the Russian Federation No. 2549055, IPC A62C 3/00, A62C 2/00, publ. 04/20/2015, selected as a prototype. The present invention proposes a method of increasing the fire safety of a submarine, according to which a hypoxic medium is formed inside each enclosed space of a sealed object with an established initial low oxygen content at normal pressure of a gas-air medium, the oxygen content being set depending on the type of pressurized room, due to the residence time and the intensity of the crew in it, namely:

- for occasionally visited tight rooms - at least 12 vol. %;

- for periodically visited premises - at least 14 vol. %;

- with a permanent shift of up to 4 hours - at least 16 vol. %;

- with a permanent shift of 10-14 hours - at least 18 vol. %;

- for permanent residence premises - at least 19 vol. %

Further, upon detection of a pre-emergency pre-fire condition or fire, a short-term control of the oxygen content in the gas-air medium is carried out for a specified time by diluting it with a nitrogen or inert gas supply, followed by returning to the initial oxygen content, namely:

- for occasionally visited tight rooms - up to 10 vol. %;

- in periodically visited rooms and premises with a permanent shift of up to 4 hours - up to 12 vol. %;

- in premises with a permanent shift of 10-14 hours and in premises of permanent residence - up to 14 vol. %

At the same time, the set time, on the one hand, should be sufficient to detect and eliminate the fire or pre-emergency pre-fire condition of the equipment, but should not exceed the permissible time spent by personnel in the hot water tank with a given oxygen content. The regulatory process itself should not lead to a threat to the safety of personnel and the operation of equipment.

This method certainly increases the fire safety of the submarine, but has limitations in terms of efficiency and also safety for personnel. These contradictions do not allow us to consider the proposed method as optimal from the point of view of the health of personnel and fire safety of submarines.

The claimed invention solves the following tasks: to prevent fire or fire on board the submarine, in the underwater position; to ensure long-term work of the crew for 60-90 days in the conditions of normobaric hot water supply without significant reduction in performance and damage to health; ensure the preservation of the basic modes of functioning of the submarine and the preservation of the operability of submarine equipment.

The technical result from the implementation of the claimed invention is to increase the fire protection of submarines during an autonomous trek and other sealed inhabited objects during sealing by creating hypoxic gas-air media with a high argon content in them, which reduce the likelihood of fire and fire due to a decrease in oxygen content and at the same time maintaining conditions for the normal life of the crew of the submarine in the conditions of prolonged sealing. Assessment of the probability of occurrence and development of a fire under the conditions of the proposed hot water supply system gives the value of reducing the probability of a fire by 10 or more times.

To achieve this technical result, in a method for ensuring fire protection of sealed inhabited objects in an autonomous mode, comprising forming, within each enclosed space of a sealed object, a hypoxic gas-air medium with a set initial reduced oxygen content at a normal gas-air pressure, the oxygen content being set depending on the type of pressurized premises due to the time spent and the intensity of the crew therein according to the invention in the environment of hypoxic-gas oxygen concentration is set at a level ensuring the prevention of the occurrence and development of a fire, and the argon concentration is raised to the level of about 27-35. %, and the argon concentration is increased at a time for the entire time of autonomous navigation.

According to the crew’s stay, the facility’s sealed rooms are divided into periodically visited, periodically visited, with a constant shift of up to 4 hours, with a constant shift of up to 10-14 hours and a permanent stay, and depending on the type of pressurized room, the oxygen content is set:

- for occasionally visited tight rooms - at least 10 vol. %;

- for periodically visited, with a permanent shift of up to 4 hours, with a permanent shift of 10-14 hours and for premises of permanent residence - up to the level of 13-14 vol. %, and these set initial values of the oxygen concentration are maintained throughout the entire time of sealing (autonomous swimming).

From the point of view of fire protection, the indicated oxygen concentrations are at or below those created in the premises of the submarine as a result of the use of a nitrogen fire extinguishing system (for example, according to OCT B5P.5616 - 2008 “Nitrogen fire extinguishing system”). This allows you to ensure high fire protection of the submarine, to prevent ignition of fire hazardous equipment. At the same time, the increased argon content within the specified limits makes it possible to ensure the submarine crew maintain the conditions for normal life in the autonomous navigation mode.

The method is as follows.

In each of the sealed rooms of a sealed object (in particular, a submarine) in the above-water position they create a gas-air medium (hot water) with a low oxygen content (hypoxic medium) by diluting it with nitrogen and argon and seal the submarine. Moreover, the oxygen content in different pressurized rooms of the submarine is maintained at a different level depending on the assigned time and intensity of the crew members in this room, and the argon concentration in the hot water tank in all rooms is brought to the level of 27-35 vol. %, in contrast to the usual content of argon in the atmosphere of the order of 1 vol. %

Since during autonomous navigation, under normal conditions, the crew keeps watch on the submarine, all work is carried out according to the schedule and the time spent in one or another pressurized room of the submarine is strictly regulated. Moreover, in some pressurized rooms of the submarine this time can be from several minutes to tens of minutes, in others it is set no more than 4 hours, in the third the crew can stay permanently. According to the time of their stay, the pressurized rooms of the submarines can be divided into episodically visited, periodically visited, with a constant shift of up to 4 hours, with a constant shift of up to 10-14 hours and a permanent stay.

Moreover, according to the claimed method, the oxygen content in the premises of the submarine, where the personnel are absent or may be sporadic, set at a predetermined level of 10 vol. %, and in other rooms where the personnel spends the main time - at the level of 13-14 vol. %

The argon content is maintained at a predetermined level throughout the entire sealing time, if necessary adding it from high-pressure cylinders installed on board the submarine. The oxygen content at a predetermined level during the entire sealing time is maintained by the ship’s regeneration system. The content of the rest of the domestic hot water is nitrogen and carbon dioxide.

Depending on the design of the pressurized object, the gas-air medium regeneration unit can be located in each controlled room of the pressurized object, or be the same for the entire pressurized object, and the cylinder nodes with argon, nitrogen and high pressure air can be made the same for the entire pressurized object .

As for the carbon dioxide content in the hot water supply system, it is controlled at a normal level normal for the atmosphere - not more than 1 vol. %

As already mentioned, the concentration of argon in all sealed rooms is increased to a level of at least 27 vol. %, but not more than 35 vol. %, which allows to provide safe conditions for the life of the crew in autonomous navigation for a long time. Moreover, studies have shown that the average amount of argon in the DHW is optimal for normal well-being of people, its average amount is about 30 vol. %

After submersion of the submarine in the case of the normal state and functioning of the ship’s technical facilities and equipment, the parameters of the hot water supply system in the sealed rooms of the submarine do not change during the entire autonomous navigation.

The effectiveness of the claimed invention lies in the fact that only by the proposed method it is safe for health and without a significant reduction in working capacity to establish for the entire period of autonomous navigation (sealing the object) such oxygen content at normal pressure that will prevent the occurrence and development of fire in the vast majority of cases, with the exception of burning special oxygen-containing substances (fuels), increasing fire safety by ten or more times.

The safety of such oxygen concentrations under the indicated argon content for personnel during long-term autonomous navigation of submarines and fire-fighting efficiency were established as a result of studies conducted by the authors.

A scientific experiment was conducted, which consisted of the continuous stay of 6 testers in a sealed facility with a hypoxic oxygen-argon-nitrogen gas medium (for example, containing oxygen 14 vol.%, Argon - 30 vol.%, Nitrogen and carbon dioxide - the rest) lasting 60 days . Over the next year, studies were conducted to assess the possible long-term effects of this experiment on the body of testers. In addition, an assessment was made of the impact on the functional state and performance of the examined individuals of re-sealing in a given argon-containing gas-air environment for 15 days. The tests were carried out on the Stand Model of the ship’s premises and equipment “MORZH” (hereinafter referred to as the Stand), developed at ASM OJSC, St. Petersburg (see the description of the stand on the Internet link http://www.oaoasm.com/ stendovoe-oborudovanie / stend-model-sudovykh-pomeshchenij-i-oboradovaniya-morzh).

In the course of the work, a complex of standardized and valid clinical, physiological, psychophysiological, laboratory and other research methods was used, which made it possible to obtain comprehensive information about the state of somatic and mental health of the testers, their functional reserves, the internal environment of the body, physical and intellectual (including camera) health.

In the process of sealing, in addition to the planned control examinations, all test participants carried out a work program consisting in daily modeling of professional activity of intellectual or operator content (in particular, work on simulators), as well as intense multimodal physical loads performed under the supervision of the test commander (strength training, exercise bike , practicing elements of hand-to-hand combat, individual special programs of physical exercises). The total duration of daily work was about 3-4 hours a day. As a rule, control functional examinations took another 3-4 hours. In addition, shift shifts were organized around the clock. Thus, the daily activities of the test participants were close to the real activities of specialists working in the conditions of pressurized objects.

As a result, all the examined persons were able to fulfill the main task of continuous stay in the conditions of "sealing" in the premises of the Stand. Cases of somatic diseases (including colds, pustular skin, dental, which are most common in conditions of prolonged sealing), refusals to carry out the planned studies, and a decrease in motivation to continue them were not noted. During the sealing period, the test participants either did not complain of well-being associated with being in the GGVS, or only noted mild and transient signs of mild dizziness, sensations of "subjective discomfort", mild general weakness or lack of air due to high-intensity physical exertion.

A daily analysis of the dynamics of control physiological parameters revealed that, when the conditions of a given HHG were present, all examined had a moderate compensatory activation of mechanisms aimed at maintaining oxygen homeostasis. It is characteristic that the severity of homeostatic reactions was characterized by significant individual variability, with a tendency to decrease as sealing continued. In particular, the reaction of systemic hemodynamics when staying in HHGS was either absent or manifested in minor hyperkinetic tendencies.

Analysis of the results of the dynamics of success of the mental (operator) activity of testers, modeled using valid methods of psychophysiological examination (see, for example: Danilova NN Psychophysiological diagnosis of functional states. - M.: Publishing house of Moscow University, 1992. - 193 pp.; Research methods in the physiology of military labor / Edited by BC Novikov. - M .: Military Publishing House, 1993. - 240 pp.), at the stages of observation revealed a generally characteristic picture of the phases of the dynamics of working capacity. At the initial stage of sealing (the “operating phase”), a moderate decrease in intellectual working capacity was noted compared with the initial normoxic level. However, as the tests continued, there was a gradual increase in the indicators of efficiency and reliability of mental (including operator) activity, so that by about 15-20 days of sealing, the success of this activity already exceeded the initial (normoxic) level ("phase of optimal performance"). In the future, up to the end of the test period, fluctuations in operator performance were observed around the achieved level, which can be regarded as a state corresponding to the “phase of full compensation” in the performance dynamics. On the whole, even at the “working-in” stage, the degree of decrease in sensory and sensorimotor qualities and the success of intellectual activity in sealing testers did not exceed 8-10% of the normoxic level.

When analyzing the dynamics of the maximum physical performance of the testers, assessed using samples with a stepwise increasing (until the threshold of anaerobic metabolism is reached) bicycle ergometric load, a decrease in aerobic performance was found in the conditions of sealing, amounting to about 12-15% of the normoxic level. This testified to a decrease in the overall functional potential of the body when under these conditions due to the natural impossibility of achieving a “normoxic” level of energy supply of submaximal and maximum work. As you know, such a decrease in maximum performance when a person is in conditions of oxygen deficiency in the environment is a sign of a mild hypoxic state in the body, in which a relatively low degree of homeostatic deviations as a whole allows specialists to perform the basic tasks of a physical activity while maintaining the necessary level of its effectiveness and reliability. It is characteristic that signs of a decrease in the physical endurance of the testers when performing local work, the general loads of the anaerobic level of energy supply, low- and medium-intensity aerobic loads were not detected throughout the entire sealing stage.

Studies of long-term (within 10 months of observation) consequences of the stay of test participants in the conditions of GGVS revealed the following facts:

- immediately after the end of the sealing stage (on the 3-4th day) against the background of a normal psychoemotional state and the absence of somatic complaints in all the examined, the indicators of mental, operator, and physical performance were at a level close to the initial one (before the test). This, in our opinion, testified to the complete preservation of the functional capabilities of the organism of the examined individuals, despite the previous 2-month stage of sealing in the conditions of GGVS;

- further observation showed the absence of significant deviations from the somatic health of all the testers, including no increase in colds in the cold seasons of the observation period compared with the previous 2-3 years. There was also no directional dynamics of mental, camera, physical performance; individual fluctuations of the studied parameters as a whole amounted to about 10-15% of their usual level, which depended on the characteristics of the individual functional state of the subject;

- for all testers, the values of the cellular and biochemical parameters of the circulating blood changed at the sealing stage “returned” to the initial level approximately 2 months after the end of the tests. Moreover, the fluctuations of the considered parameters during the subsequent observation period did not have directional dynamics in any of the examined individuals, which, in our opinion, was evidence of the safety (“intactness”) of the main regulatory, metabolic, plastic, protective and other processes in the body of the test participants .

An analysis of the research results allowed us to conclude that it is possible and safe for a person to remain continuously in a given normobaric argon-containing hypoxic environment for 60 days. Under such environmental conditions, no unacceptable deviations in the health and functional state of any of the testers were revealed. At the same time, the fulfillment of the tasks of professional activity (intellectual and physical) took place without significant damage to its effectiveness and reliability.

Thus, the possibility of implementing a safe way to increase the fire protection of submarines during an autonomous trip by using hypoxic media with a high argon content has been confirmed.

Claims (7)

1. A method of ensuring fire protection of sealed inhabited objects, mainly submarines, in an autonomous mode, comprising forming, within each enclosed space of a sealed object, a hypoxic gas-air environment with an established initial low oxygen content at a normal gas-air pressure, the oxygen content being set depending on the type of pressurized room due to the time spent and the intensity of the crew in it, characterized in that then in a hypoxic gas-air environment the oxygen concentration is set at a level that prevents the onset and development of a fire, and the argon concentration is increased to a level of 27-35 vol.%. 2. The method according to p. 1, characterized in that the concentration of argon in a hypoxic gas-air environment is increased at a time for the entire duration of autonomous navigation. 3. The method according to p. 1, characterized in that according to the time of stay, the sealed rooms of the object are divided into periodically visited, periodically visited, with a constant shift of up to 4 hours, with a constant shift of up to 10-14 hours and a permanent stay. 4. The method according to p. 1, characterized in that for pressurized rooms of the object as the initial values of the oxygen concentration at normal pressure of the gas-air medium set the following: - for occasionally visited tight rooms - at least 10 vol.%; - for periodically visited, with a permanent shift of up to 4 hours, with a permanent shift of 10-14 hours and for premises of permanent residence - within 13-14 rpm. % 5. The method according to p. 4, characterized in that the set initial values of the oxygen concentration are maintained throughout the entire time of autonomous swimming.