A method for hazard assessment of ship deck fuel handling environment

Abstract

This invention discloses a method for hazard assessment of the ship deck fuel handling environment, comprising: constructing a first-type test facility based on the ship deck fuel handling environment; conducting multi-level tests on the first-type test facility under different radiation conditions, different radiation times, and fuel vapor ignition at different test temperatures to obtain first-type test results; improving the first-type test facility to obtain a second-type test facility; controlling the test temperature in the second-type test facility to the highest temperature of the first-type test results and then starting radiation testing according to a preset frequency and power to obtain second-type test results; and conducting a hazard assessment of the ship deck fuel handling environment based on the first-type and second-type test results to obtain an assessment result. This invention enables a comprehensive assessment of the hazards of the ship deck fuel handling environment. The method not only improves the accuracy of the assessment but also provides a scientific basis for developing corresponding safety measures and operating procedures.

Description

Technical Field

[0001] This invention belongs to the field of fuel operation safety technology, specifically relating to a method for testing and assessing the hazards of fuel operation environments on ship decks. Background Technology

[0002] Surface ships carrying aircraft need to conduct numerous refueling and unloading operations. Simultaneously, the ship's high-power equipment, such as radar and communication systems, generates electromagnetic radiation fields in the refueling area. When the energy is sufficient, it may induce enough energy in the metal structure to form an electric arc or spark. When the fuel vapor-air mixture ratio is appropriate and the ambient temperature is suitable, there is a certain probability that the arc or spark formed by the radio frequency field will ignite the fuel, potentially causing serious consequences such as fire or explosion. Currently, domestic standards GJB1389A-2005 (System Electromagnetic Compatibility Requirements), GJB1446.40-1992 (Electromagnetic Environment Requirements for Ship System Interfaces), and HJB34A-2007 (Ship Electromagnetic Compatibility Specifications) provide relevant qualitative requirements regarding the electromagnetic environment's impact on fuel and related protection measures. Only the U.S. Navy Technical Manual (NAVSEA OP 3565) provides safety limits for the electromagnetic environment's hazards to automotive gasoline and aviation gasoline (power density limit of 0.009 mW / cm2 for frequencies less than 225 MHz and power density limit of 5 W / cm2 for frequencies greater than 225 MHz), but does not provide safety limits for electromagnetic environment hazards to high flash point fuels.

[0003] Therefore, it is necessary to conduct electromagnetic safety tests on ship deck fuel handling to investigate the impact of electromagnetic radiation from high-power equipment on the safety of aviation kerosene. This invention proposes a hazardous testing and assessment method for the ship deck fuel handling environment. It constructs a direct irradiation environment of strong electromagnetic radiation on the ship deck and uses an extreme simulation device to assess the electromagnetic safety of fuel handling, providing support for the detailed design of subsequent operating procedures for ship deck refueling and unloading operations. Summary of the Invention

[0004] In view of this, the present invention proposes a method for hazard assessment of the ship deck fuel handling environment. This method enables a more comprehensive assessment of the hazards of the ship deck fuel handling environment. It not only improves the accuracy of the assessment but also provides a scientific basis for developing corresponding safety measures and operating procedures, which is of great significance for ensuring the safety of ship deck fuel handling.

[0005] To achieve the above objectives, the present invention provides the following technical solution:

[0006] This invention provides a method for hazard assessment of the ship deck fuel handling environment, comprising:

[0007] The first type of experimental facility is a simulated refueling device with metal fuel containers as its main feature, built based on the actual ship deck fuel operation environment.

[0008] Based on the controlled variable testing method, multi-stage tests were conducted on the first type of test facility under different radiation conditions, different radiation times, and fuel vapor ignition at different test temperatures to obtain the first type of test results.

[0009] The first type of test facility was improved by replacing the metal fuel container with a transparent fuel container and setting two discharge electrodes with opposite tips above the transparent fuel container to obtain the second type of test facility.

[0010] Based on the results of the first type of test, the maximum test temperature is determined. After the test temperature in the second type of test facility is controlled to the maximum test temperature, the radiation test is started according to the preset frequency and power to obtain the results of the second type of test.

[0011] A hazard assessment of the ship deck fuel handling environment was conducted based on the results of the first and second type of tests, and the assessment results were obtained.

[0012] Preferably, the first type of testing facility includes the device under test and the testing equipment, wherein:

[0013] The equipment under test includes the test fuel, metal fuel container, and refueling nozzle. The test fuel is a test fuel that meets the requirements of relevant standards and specifications, and its type and model are consistent with the fuel actually used in the ship deck fuel operation system.

[0014] The test equipment includes electromagnetic environment construction equipment and test data acquisition equipment. The electromagnetic environment construction equipment includes a signal source, radio frequency power amplifier, radiating antenna, field strength monitor, oil and gas concentration tester, temperature sensor, wind speed and direction sensor, and heating plate.

[0015] The experimental data acquisition equipment includes a camera and an oil and gas concentration analyzer.

[0016] Preferably, based on the controlled variable testing method, multi-stage tests are conducted on the first type of test facility under different radiation conditions, different radiation times, and fuel vapor ignition at different test temperatures. The results of the first type of test include:

[0017] Step S101: Heat the fuel until it reaches the specified temperature, then test and record the concentration of fuel vapor at the fuel container opening, and turn on the radiation system.

[0018] Step S102: Irradiate the simulated refueling device test facility, test and record the fuel vapor ignition and fuel vapor concentration;

[0019] Step S103: Change the operating conditions of the radiation source and continue the experiment;

[0020] Step S104: Determine whether the test of different radiation source conditions has been completed. If not, return to step S102; if completed, proceed to the next step.

[0021] Step S105: Continue the experiment by changing the radiation time.

[0022] Step S106: Determine whether the test for different radiation durations has been completed. If not, return to step S102; if completed, proceed to the next step.

[0023] Step S107: Change the test temperature and continue the test;

[0024] Step S108: Determine whether the test at different test temperatures has been completed. If not, return to step S101. If completed, generate the first type of test result based on the collected data.

[0025] Preferably, a hazard assessment of the ship deck fuel handling environment is conducted based on the results of the first type of test and the results of the second type of test, and the assessment results include:

[0026] Based on the results of the first and second type of tests, the ignition of fuel vapor under different radiation conditions, different radiation times, and different test temperatures was determined, and multiple ignition critical points were extracted. Radiation conditions Radiation time and test temperature ,in , Indicates the radiation frequency. Indicates radiated power. This represents the total number of ignition critical points;

[0027] Based on the relevant data of multiple ignition critical points, a scattered data representation in a four-dimensional data space is constructed. By using radial basis functions to perform data interpolation and smoothing of the ignition critical points in the four-dimensional data space, a scattered data model is obtained.

[0028] Based on the ignition critical point, the fuel is divided into two states: ignition and non-ignition. The scatter data model is then divided into two binary categories: ignition and non-ignition. This results in a relatively simple evaluation model.

[0029] Obtain a set of historical environmental data of the ship deck fuel operation environment during actual operation, and for any set of historical environmental data, calculate the shortest distance between the historical environmental data and the boundary of the evaluation model.

[0030] When the shortest distance is less than the preset danger distance threshold, the historical environmental data and its corresponding time point are recorded as a danger state.

[0031] The risk assessment of the deck fuel handling environment is conducted by statistically analyzing all hazardous states recorded within any preset period and their corresponding shortest distances, and by weighted summation based on the preset relationship between distances and weights.

[0032] The present invention has achieved at least the following beneficial effects:

[0033] 1. This invention enables a more comprehensive assessment of the hazards of ship deck fuel handling environments. This method not only improves the accuracy of the assessment but also provides a scientific basis for developing corresponding safety measures and operating procedures, which is of great significance for ensuring the safety of ship deck fuel handling operations.

[0034] Other advantages, objectives, and features of the invention will be set forth in the following description and will be apparent to those skilled in the art in some respects, or may be learned by practice of the invention. The objectives and other advantages of the invention can be realized and obtained through the following description. Attached Figure Description

[0035] To make the objectives, technical solutions, and beneficial effects of this invention clearer, the following figures are provided for illustration:

[0036] Figure 1 This is a flowchart illustrating the overall steps of a hazard assessment method for a ship deck fuel handling environment according to an embodiment of the present invention.

[0037] Figure 2 This is a schematic diagram of the layout of the first type of test facility in an embodiment of the present invention;

[0038] Figure 3 This is a schematic diagram of the layout of the second type of test facility in an embodiment of the present invention;

[0039] Figure 4 This is a flowchart of the experimental steps in an embodiment of the present invention. Detailed Implementation

[0040] The preferred embodiments of the present invention will be described below with reference to the accompanying drawings. It should be understood that the preferred embodiments described herein are for illustration and explanation only and are not intended to limit the present invention.

[0041] The present invention provides a method for hazard assessment of the ship deck fuel handling environment, referring to... Figure 1 To assess the safety of fuel operations such as refueling and unloading on ship decks, considering the radiation emitted by high-power equipment such as radar and communication systems, including:

[0042] The first type of experimental facility is a simulated refueling device with metal fuel containers as its main feature, built based on the actual ship deck fuel operation environment.

[0043] Based on the controlled variable testing method, multi-stage tests were conducted on the first type of test facility under different radiation conditions, different radiation times, and fuel vapor ignition at different test temperatures to obtain the first type of test results.

[0044] The first type of test facility was improved by replacing the metal fuel container with a transparent fuel container and setting two discharge electrodes with opposite tips above the transparent fuel container to obtain the second type of test facility.

[0045] Based on the results of the first type of test, the maximum test temperature is determined. After the test temperature in the second type of test facility is controlled to the maximum test temperature, the radiation test is started according to the preset frequency and power to obtain the results of the second type of test.

[0046] A hazard assessment of the ship deck fuel handling environment was conducted based on the results of the first and second type of tests, and the assessment results were obtained.

[0047] The working principle and beneficial effects of the above technical solution are as follows: By constructing a first-type test facility simulating a refueling device, this invention can simulate the actual ship deck fuel handling environment and conduct precise test evaluations. This simulation test method improves the accuracy and reliability of safety assessments for ship deck fuel handling. By employing a controlled variable testing method to conduct multi-level tests on the first-type test facility, including different radiation conditions, time, and temperature conditions, this invention can systematically study the influence of various factors on fuel vapor ignition. This method enhances the controllability of test conditions and increases the diversity of tests. By improving the first-type test facility and introducing a second-type test facility with a transparent fuel container and discharge electrodes, this invention can more realistically simulate the actual environment of a ship deck. This improved test facility not only improves the practicality of the test but also allows for more precise research on the influence of electromagnetic radiation on fuel vapor ignition, thus providing more accurate data support for the hazard assessment of the ship deck fuel handling environment. Through improved test facilities and controlled test conditions, this invention can more comprehensively assess the hazards of the ship deck fuel handling environment. This method not only improves the accuracy of assessments but also provides a scientific basis for developing corresponding safety measures and operating procedures, which is of great significance for ensuring the safety of ship deck fuel operations.

[0048] In one specific embodiment, the present invention provides the experimental environment, experimental site, tested equipment, experimental setup, pre-experimental preparations, experimental procedures, and evaluation of experimental results, as detailed below:

[0049] 1. Test Environment

[0050] The test should be conducted under normal atmospheric conditions, with clear skies, no rain or snow, and wind speeds less than 3-4. The ambient temperature, humidity, and atmospheric pressure during the test should not exceed the allowable ranges for the testing instruments and the test specimen under normal operating conditions.

[0051] 2. Test site

[0052] The test site should be selected based on the needs of the test project and specific site conditions, including open test areas and field test sites. The selection of the test site should meet the following requirements:

[0053] a) The test area should be large enough to ensure that the electromagnetic radiation and the distance between the test piece and adjacent structures and other objects are not less than 1.5 times the radiation distance, so as to prevent the proximity effect from adversely affecting the test results, adjacent structures and other objects;

[0054] b) The test site should have necessary safety measures such as warnings and barriers to prevent high field strength from causing harm to personnel;

[0055] c) Good grounding and isolation protection measures should be in place to avoid the impact of ground potential rise caused by high field strength on equipment and test specimens in the site.

[0056] d) Provide the power, hydraulic, ventilation, fire protection, safety and other necessary support or guarantee equipment and facilities required for the normal operation of SUT / EUT and test equipment.

[0057] 3. Test equipment

[0058] The test equipment includes: the test fuel, fuel container, fuel nozzle simulator, and copper discharge electrodes, and should meet the following requirements:

[0059] a) The test fuel shall be a test fuel that meets the requirements of relevant standards and specifications, and the type and model shall be consistent with the fuel actually used in the system.

[0060] b) Fuel containers should be available in two types: transparent and metal, to simulate small fuel leaks and fuel storage conditions in the system, respectively; the capacity should be no less than 4L; and the bottom should be flat to allow full contact with the heating plate.

[0061] c) The material and electromagnetic properties of the fuel nozzle simulation device are consistent with those of the actual fuel nozzle connector.

[0062] d) The number of copper discharge electrodes shall not be less than two, with a diameter of 5mm to 8mm and a length of 30mm to 90mm.

[0063] The test equipment consists of the test fuel, the metal fuel container, and the fuel nozzle simulation device, which together constitute the simulated refueling operation test facility; the transparent fuel container and the copper discharge electrode together constitute the metal discharge electrode test facility.

[0064] 4. Test equipment

[0065] The test equipment includes electromagnetic environment construction equipment and test data acquisition equipment.

[0066] (1) Electromagnetic environment construction equipment

[0067] The test equipment includes: a signal source, an RF power amplifier, a radiating antenna, a field strength monitor, an oil and gas concentration analyzer, a temperature sensor, a wind speed and direction sensor, and a heating plate. The basic requirements for the test equipment are as follows:

[0068] a) Field strength monitors, oil and gas concentration testers, temperature sensors, and wind speed and direction sensors should have sufficient dynamic range;

[0069] b) The heating plate should have a flat heating surface structure and controllable temperature rise, and be used to place and heat the fuel container;

[0070] c) The camera should have continuous recording capability and sufficient resolution to capture intermittent discharge arcing effects;

[0071] d) The signal source should be able to cover the required frequency range and be modulated with pulses of a specified duty cycle, or have the modulation scheme specified in the test outline;

[0072] e) The signal source, RF power amplifier and antenna should be able to generate the required field strength level in the test area, and their harmonics should be as small as possible. The field strength at each harmonic frequency should be at least 6 dB lower than the fundamental field strength.

[0073] f) Prioritize the use of high-power radiation source equipment or prototypes with system configurations to replace signal sources, RF power amplifiers and antennas to generate the required field strength level in the test area.

[0074] (2) Test data acquisition equipment

[0075] The main sampling equipment used in the experiment included a camera and an oil and gas concentration analyzer.

[0076] The main technical specifications of the camera are as follows:

[0077] a) Lens magnification: not less than 4x;

[0078] b) Pixels: No less than 4 million;

[0079] c) Output resolution: not less than 2560 1440@30fps;

[0080] d) Night mode is supported.

[0081] The main technical specifications of the oil and gas concentration analyzer are as follows:

[0082] a) Sampling method: Pump suction;

[0083] b) Electromagnetic radiation (EMI / RF) protection rating: EMC Directive 2004 / 108 / EEC;

[0084] c) Detection range 10.6 eV: 0.1 ppm to 15,000 ppm;

[0085] d) Resolution: 0.1ppm;

[0086] e) Response time: (T90) 2s.

[0087] 5. Test setup

[0088] During measurement, arrange the radiation system and the tested equipment according to the experimental requirements. Place the fuel container on the electric heating plate, and position the camera near the fuel container with its viewing angle directly facing the fuel container and its upper opening. Fix the fuel vapor concentration meter at the upper opening of the fuel container. Place the field strength monitor near the fuel container. Refer to the appendix for the experimental equipment setup. Figure 2 .

[0089] After completing the experiment on the impact of electromagnetic radiation on fuel vapor concentration and safety, the simulated refueling operation test facility was replaced with a copper discharge electrode. A camera was positioned near the fuel container, with its viewing angle directly facing the fuel container and its opening above it; a field strength monitor was also positioned near the fuel container. The test equipment setup is as shown in the attached diagram. Figure 3 .

[0090] The placement of cameras, oil and gas concentration testers, and field strength monitors should avoid obstructing the radiation system from irradiating the simulated refueling device test facilities and copper discharge electrodes.

[0091] 6. Preparatory work before the experiment

[0092] Before the formal test, the high-power radiation source configured in the system was analyzed for parameters such as frequency, transmit power, antenna gain, and duty cycle. Based on the actual usage of the system, the radiation field strength generated in the designated area was predicted through simulation or pre-testing methods to determine the test conditions and formulate a detailed test plan, including the following:

[0093] a) Determine the key data that needs to be detected and monitored, and the locations of the data acquisition systems;

[0094] b) For different radiation sources, determine the maximum electromagnetic radiation level that the tested equipment may be in, and calculate the value after the radiation level is further increased by 6dB, and determine the amplitude, frequency and other parameters of the radiation field strength used in the test;

[0095] c) Based on the radiation field strength parameters used in the experiment, analyze the parameter settings such as the location of the radiation source, transmission power, and beam direction; verify the radiation source to confirm that it is working properly; and confirm the type and performance requirements of the data acquisition system, as well as the radiation protection measures that should be taken for the data acquisition system.

[0096] d) Select room temperature, fuel closed-cup flash point temperature, and system normal operating upper limit temperature as the test temperature for the test; unless otherwise specified, room temperature is set to 25℃, system normal operating upper limit temperature is set to 65℃, and flash point temperature is the lowest temperature at which the test fuel vapor ignites.

[0097] e) Determine the verification criteria and result evaluation criteria;

[0098] f) Evaluate existing analytical data and experimental data obtained from previous experiments, and incorporate them into experimental plans and predictive analyses to expand or narrow the scope of the experiment.

[0099] 7. Test Procedure (Refer to) Figure 3 )

[0100] The experimental steps are as follows:

[0101] a) Fill a test metal fuel container with no less than 4L of fuel, heat it with an electric heating plate, and measure the temperature with an infrared thermometer.

[0102] b) Start heating. Once the temperature reaches the test temperature "room temperature", turn on the oil and gas concentration tester and record the oil and gas concentration.

[0103] c) Set the test temperature, turn on the radiation system, set the frequency, power, beam direction, etc. according to the test outline, and start radiation. Test and record the fuel vapor ignition and fuel vapor concentration.

[0104] d) Fix the test fuel temperature and radiation time, change the radiation source conditions (change the radiation source frequency, power, etc. according to the test outline), and repeat the test according to steps b) and c).

[0105] e) Keep the test temperature and radiation intensity fixed, and change the radiation time (irradiation for 30s, 1min, and 3min respectively), and repeat the test according to steps b) and c);

[0106] f) Change the test temperature (flash point temperature, upper limit of normal system operating temperature), and repeat the test according to steps b), c), d), and e);

[0107] g) If no fuel ignition occurs in the above tests, replace the metal fuel container with a transparent, microwave-transparent fuel container, and place two copper discharge electrodes with opposite tips and a 1mm gap on top of it. Set the test temperature to the highest temperature in the above test steps, turn on the radiation system, set the frequency and power according to the test outline, and start radiation. Test and record the electrode tip discharge and fuel vapor ignition.

[0108] h) During the test, the electromagnetic radiation field strength near the fuel container was continuously monitored and recorded, and meteorological elements, including temperature, humidity, wind speed, and wind direction, were monitored and recorded in real time.

[0109] 8. Evaluation of test results

[0110] If no electric arc or fuel vapor ignition occurs during the test, the electromagnetic radiation and fuel safety test is passed.

[0111] The working principle and beneficial effects of the above technical solution are as follows: The present invention proposes a test method for the hazards of electromagnetic radiation from surface ships to deck fuel operations. It utilizes a high-power radiation source equipment / prototype or an equivalent radiation source composed of a signal source, radio frequency power amplifier, and antenna to form a simulated electromagnetic environment. Two types of fuel containers are designed in conjunction with heaters, refueling nozzles, copper electrodes, etc., to simulate extreme conditions in fuel loading and unloading operations. By detecting the ignition of fuel vapor and the concentration of fuel vapor, the safety of fuel operations can be accurately analyzed. This method can effectively assess the harmful effects of strong electromagnetic radiation from the ship deck on deck fuel operations, and provide support for the detailed design of subsequent operating procedures for deck fuel loading and unloading operations on surface ships.

[0112] In a preferred embodiment, a hazard assessment of the ship deck fuel handling environment is conducted based on the results of the first type of test and the results of the second type of test, and the assessment results include:

[0113] Based on the results of the first and second type of tests, the ignition of fuel vapor under different radiation conditions, different radiation times, and different test temperatures was determined, and multiple ignition critical points were extracted. Radiation conditions Radiation time and test temperature ,in , Indicates the radiation frequency. Indicates radiated power. This represents the total number of ignition critical points;

[0114] Based on the relevant data of multiple ignition critical points, a scattered data representation in a four-dimensional data space is constructed. By using radial basis functions to perform data interpolation and smoothing of the ignition critical points in the four-dimensional data space, a scattered data model is obtained.

[0115] Based on the ignition critical point, the fuel is divided into two states: ignition and non-ignition. The scatter data model is then divided into two binary categories: ignition and non-ignition. This results in a relatively simple evaluation model.

[0116] Obtain a set of historical environmental data of the ship deck fuel operation environment during actual operation, and for any set of historical environmental data, calculate the shortest distance between the historical environmental data and the boundary of the evaluation model.

[0117] When the shortest distance is less than the preset danger distance threshold, the historical environmental data and its corresponding time point are recorded as a danger state.

[0118] The risk assessment of the deck fuel handling environment is conducted by statistically analyzing all hazardous states recorded within any preset period and their corresponding shortest distances, and by weighted summation based on the preset relationship between distances and weights.

[0119] The working principle and beneficial effects of the above technical solution are as follows: By analyzing the results of the first and second types of tests, this invention can determine the ignition of fuel vapor under different radiation conditions, times, and test temperatures, and extract multiple ignition critical points. This precise analysis helps to deeply understand the ignition characteristics of fuel vapor and provides accurate data support for subsequent hazard assessment. By interpolating and smoothing the scattered data in the four-dimensional data space using radial basis functions, this invention can construct a comprehensive scattered data model. This model not only reflects the complexity of fuel vapor ignition but also provides a reliable mathematical basis for hazard assessment. By performing binary partitioning on the scattered data model, this invention can create a simple evaluation model to distinguish between fuel ignition and non-ignition states. Combined with historical environmental data sets, this invention can accurately assess the risk of fuel operations and can also calculate the distance between the model and the evaluation model boundary in real time, recording a dangerous state when the distance is less than a preset threshold. This real-time monitoring and assessment method can promptly identify potential safety risks and provide effective decision support for the safety management of the ship deck fuel operation environment. This invention provides an efficient and accurate method for assessing the hazards of ship deck fuel handling environments by combining experimental data, four-dimensional data spatial analysis, and real-time monitoring technology. This method not only improves the accuracy and efficiency of the assessment but also enhances the ability to prevent and respond to potential hazards, which is of great significance for ensuring the safety of ships and their personnel.

[0120] Finally, it should be noted that the above preferred embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit it. Although the present invention has been described in detail through the above preferred embodiments, those skilled in the art should understand that various changes can be made to it in form and detail without departing from the scope defined by the claims of the present invention.

Claims

1. A method for hazard assessment of the ship deck fuel handling environment, characterized in that, include: The first type of experimental facility is a simulated refueling device with metal fuel containers as its main feature, built based on the actual ship deck fuel operation environment. Based on the controlled variable testing method, multi-stage tests were conducted on the first type of test facility under different radiation conditions, different radiation times, and fuel vapor ignition at different test temperatures to obtain the first type of test results. The first type of test facility was improved by replacing the metal fuel container with a transparent fuel container and setting two discharge electrodes with opposite tips above the transparent fuel container to obtain the second type of test facility. Based on the results of the first type of test, the maximum test temperature is determined. After the test temperature in the second type of test facility is controlled to the maximum test temperature, the radiation test is started according to the preset frequency and power to obtain the results of the second type of test. A hazard assessment of the ship deck fuel handling environment was conducted based on the results of the first and second type of tests, and the assessment results were obtained. The aforementioned risk assessment of the ship deck fuel handling environment based on the results of the first and second type of tests, and the assessment results include: Based on the results of the first and second type of tests, the ignition of fuel vapor under different radiation conditions, different radiation times, and different test temperatures was determined, and multiple ignition critical points were extracted. Radiation conditions Radiation time and test temperature ,in , Indicates the radiation frequency. Indicates radiated power. This represents the total number of ignition critical points. Based on the relevant data of multiple ignition critical points, a scattered data representation in a four-dimensional data space is constructed. By using radial basis functions to perform data interpolation and smoothing of the ignition critical points in the four-dimensional data space, a scattered data model is obtained. Based on the ignition critical point, the fuel is divided into two states: ignition and non-ignition. The scatter data model is then divided into two binary categories: ignition and non-ignition. This results in a relatively simple evaluation model. Obtain a set of historical environmental data of the ship deck fuel operation environment during actual operation, and for any set of historical environmental data, calculate the shortest distance between the historical environmental data and the boundary of the evaluation model. When the shortest distance is less than the preset danger distance threshold, the historical environmental data and its corresponding time point are recorded as a danger state. The risk assessment of the deck fuel handling environment is conducted by statistically analyzing all hazardous states recorded within any preset period and their corresponding shortest distances, and by weighted summation based on the preset relationship between distances and weights.

2. The method for hazard assessment of ship deck fuel handling environment according to claim 1, characterized in that, The first type of testing facility includes the device under test and the testing equipment, wherein: The equipment under test includes the test fuel, metal fuel container, and refueling nozzle. The test fuel is a test fuel that meets the requirements of relevant standards and specifications, and its type and model are consistent with the fuel actually used in the ship deck fuel operation system. The test equipment includes electromagnetic environment construction equipment and test data acquisition equipment. The electromagnetic environment construction equipment includes a signal source, radio frequency power amplifier, radiating antenna, field strength monitor, oil and gas concentration tester, temperature sensor, wind speed and direction sensor, and heating plate. The experimental data acquisition equipment includes a camera and an oil and gas concentration analyzer.

3. The method for hazard assessment of ship deck fuel handling environment according to claim 1, characterized in that, The controlled variable testing method involves conducting multi-stage tests on the first type of test facility under different radiation conditions, different radiation times, and different test temperatures for fuel vapor ignition. The results of the first type of test include: Step S101: Heat the fuel until it reaches the specified temperature, then test and record the concentration of fuel vapor at the fuel container opening, and turn on the radiation system. Step S102: Irradiate the simulated refueling device test facility, test and record the fuel vapor ignition and fuel vapor concentration; Step S103: Change the operating conditions of the radiation source and continue the experiment; Step S104: Determine whether the test of different radiation source conditions has been completed. If not, return to step S102; if completed, proceed to the next step. Step S105: Continue the experiment by changing the radiation time. Step S106: Determine whether the test for different radiation durations has been completed. If not, return to step S102; if completed, proceed to the next step. Step S107: Change the test temperature and continue the test; Step S108: Determine whether the test at different test temperatures has been completed. If not, return to step S101. If completed, generate the first type of test result based on the collected data.

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