Search equipment: life detector type, performance and use maintenance

Searching for survivors quickly and efficiently is the top priority for firefighting forces to dispose of fires and various disaster sites. At present, the equipment used for fire search at home and abroad mainly includes infrared thermal imaging cameras and life detectors . Life detectors include audio life detectors , video life detectors, and radar life detectors .

First, infrared thermal imager

Handheld infrared life detector

Infrared thermal imaging products can be classified into two major categories: cold type and non-cool type. The most advanced infrared thermal imager currently has a temperature sensitivity of 0.05 °C . No matter whether it is day or night, it can be used to detect hidden objects. Its distance can reach 100 meters. This device can be directly observed by firefighters in their hands, and can also be worn on the head or mounted on a helmet for observation. Even when the smoke curtain is enveloping and the view is completely blocked, the imaging effect will not be affected.

The infrared thermal imager for firefighting is an uncooled type, which is classified into a salvage thermal imager and a detection thermal imager according to its application. The salvage thermal imager generally has three display modes of white heat, black heat, and false color in the infrared mode, and has the functions of temperature measurement, power consumption display, image noise reduction, and continuous operation at a specific ambient temperature ( such as high temperature ). Higher shell protection rating.

The salvage thermal imager is mainly used for fire reconnaissance, personnel search and rescue, auxiliary fire extinguishing and fire field cleaning in firefighting and rescue. It is especially suitable for assisting firefighters to carry out firefighting and rescue operations in the environment of smoke, darkness, high temperature and other environmental conditions. Detecting thermal imagers are generally used in electrical equipment and petrochemicals.

1 . working principle

Infrared thermal imaging cameras use the surrounding objects to emit thermal infrared rays continuously to detect objects beyond the range of visible light that the naked human eye cannot directly detect. Different infrared images can be obtained by using a detector to measure the difference in infrared rays between the target itself and the background. The image formed by the thermal infrared rays is called a thermal image. Unlike the visible light image of the target, the thermal image of the target is not the target visible light image seen by the human eye, but the temperature distribution image of the target surface. In other words, infrared thermal imaging makes it impossible for the human eye to directly see the surface temperature distribution of the target, and becomes a thermal image representing the temperature distribution of the target surface that can be seen by the human eye.

2 . structure

The thermal imaging camera consists of a lens assembly, a movement assembly, a display device and a power supply.

3 , the main technical performance

( 1 ) Basic parameters

1 sample frame rate: ≥ 25 frames /s .

2 Detector type: Non-refrigerated focal plane detectors are generally used.

③ operating band: 8 μ m ~ 14 μ m .

4 use of environmental requirements: working environment temperature: -10 °C ~ +50 °C . Specific operating ambient temperature: > 50 °C and ≤ 260 °C . Working environment humidity: ≤ 85% (40 °C ) . Storage ambient temperature: -30 °C ~ +60 °C . Storage environment humidity: ≤ 93% (40 °C ) .

( 2 ) Functional requirements

1 Display function: In the infrared mode, it has three display modes: white heat, black heat, and false color. It has temperature measurement value and battery consumption proportion display function.

2 image freeze function (the rescue camera does not have ) .

3 Image storage function (The salvage camera may not be available ) .

4 image noise reduction.

5 True recovery of the captured thermal image function (the rescue type thermal imager may not be available )

6 operation prompts function: has the Chinese operation menu or the prompt function (the salvage thermal imager may not have ) .

7 Correction function: After inputting target distance, target emissivity, ambient temperature, and relative humidity, the effect of corrected atmospheric transmittance and target surface emissivity on the measurement result is automatically calculated (the salvage-type thermal imager may not have ) .

( 3 ) Performance requirements

1 Quality: ≤ 3kg ( including battery ) .

2 Spatial Resolution: Salvage Thermal Imager: (3 ~ 4) mrad . Detection thermal imager: ≤ 2.5mrad .

3 Noise equivalent temperature difference (NETD): ambient temperature is 23 °C ± 5 °C , focal length 50mm , F number is 1 , NETD ≤ 0.2K . 4 temperature range: -20 °C ~ +500 °C .

5 Allowable error: Salvage thermal imager: ± 10 °C or ± 10% of the measured value ( °C ) . Detection thermal imager: ± 2 °C or ± 2% of the measured value .

6 temperature drift: ≤ 2 °C or 2% of the black body set temperature .

7 Continuous stable working time: ≥ 2h .

⑧ ambient temperature for certain hours (for rescue purposes thermal imager): When 80 ℃, 30min. At 120 °C , 10min . 260 °C , 5min .

9 Enclosure protection level: Salvage thermal imager should reach IP67 , detection thermal imager should reach IP54 .

10 Environmental Adaptability: The infrared thermal imager should have certain high temperature resistance, low temperature resistance, heat resistance, vibration resistance, impact resistance, and drop resistance.

In addition, the salvage thermal imager should also have the ability to simulate the fire scene imaging, that is, the image of the target body can be clearly observed in the smoke.

4 、How to use

Install the battery box Turn on the power switch and wait until the self-test is complete.

5 . Maintenance and precautions

1 It is forbidden to collide the thermal imager with other things during operation.

2 When the instrument is used for a long time, remove the battery from the instrument to avoid battery leakage.

3 The instrument should be handled lightly and stored in a dry and ventilated space.

Avoid moisture, high temperature storage.

4 Try to avoid direct observation of burning or molten metals, molten glass, high-voltage arcs, and the sun for long periods of time.

5 Do not use abrasive cloth or any organic solvent to clean the equipment.

6 It is forbidden to use high-pressure water vapor to clean the instrument. Any eroded or hard-to-remove stain on the battery case or battery contact surface can be erased with the eraser.

7 The infrared camera is a precision instrument. Non-professional technicians and maintenance personnel are not allowed to dismantle it.

Second, audio life detector

A new generation of audio and video life detector

The Audio Life Detector is a sound wave detector. It uses a special micro-electronic processor to identify tiny vibrations that propagate in air or solids. It is suitable for searching for survivors trapped under concrete, rubble or other solids. Identify voices from survivors such as shouting, tapping, scribing, or tapping. You can also filter the surrounding background noise.

An audio life detector can connect multiple audio sensors. The following figure is a life detector with a full range of audio sensors that can receive 2 , 4 or 6 sensor information at the same time, and can display any two sensor information at the same time. It is equipped with a small walkie-talkie that can talk to survivors.

The main technical performance of the audio life detector is:

1 Probe frequency: 1Hz to 3000Hz .

â‘¡ Working Time: 6 on a rechargeable battery, can work for 24 hours.

3 External DC input: 10.8V to 28.8V .

4 Storage temperature: -40 °C to +70 °C.

5 operating temperature: -30 °C ~ +60 °C.

6 quality: ≤ 20kg .

Third, video life detector

Underwater video life detector

The video life detector is a special tool for searching the victims under the collapsed buildings and in the narrow space. It provides search and rescue personnel with information on the victims under the rubble through high-definition video and audio signals.

1 . Equipment composition

The video life detector is generally composed of a probe lens, a probe rod, a plug-in miniature liquid crystal display, an earphone, a microphone, and a connection cable. The probe rod can be freely retracted and is especially suitable for detection of multiple layers of debris; the top probe lens can be rotated 180 ° by the handle . There are 16 cold light emitting diodes around the probe lens , and the visible distance is up to 3m under full dark background .

2 . The main technical parameters

( 1 ) Probe Lens: 1/4 inch color CCD , 380 lines or more, automatic iris.

( 2 ) Lights: 16 white release diodes.

( 3 ) Display: 5 inch plug-in TFT high-definition LCD monitor.

( 4 ) Control system: single button switch, lighting control.

( 5 ) Lens adjustment: Rotate 180 degrees left and right .

( 6 ) Probe Rod: Scalable 800mm to 1200mm .

( 7 ) Probe weight: 2kg ( with display ) .

( 8 ) Lens OD: 43mm .

( 9 ) Visual angle: 230 °.

( 10 ) Battery: 2 section lead-acid batteries, capacity 2.5Ah .

( 11 ) Continuous working time: ≥ 2h .

( 12 ) Charging time: 22h .

( 13 ) Operating temperature: -10 °C to +60 °C.

3 . Instructions

Rescuers put the whole outfit on their bodies, wearing headphones, holding the joystick in the left hand, pressing the handle with the right hand, and the monitor on the joystick can clearly display the front image; the camera installed at the probe of the detector can be rotated automatically, once the rescue Dim lights and you can turn on the lights. As a professional life search tool, it is ideal for rescue search operations in collapsed buildings or in narrow spaces.

4 . maintenance

1 When the detector is not in use, the battery should be removed. Otherwise, the detector will be in a standby state , which will affect the battery's continuous power supply time.

2 The battery should be fully discharged before each charge. Do not charge and discharge regularly for a long time to prolong battery life.

3 Apply special lens paper or dry soft cloth to the surface of the camera.

4 Microphones and monitors cannot be used on rainy days. If necessary, take measures to prevent moisture.

5 Carefully read the instruction manual before use to master the operation method and instrument function.

5 . Save request

1 The detector should be kept in a clean, dry and well-ventilated indoor environment.

2 The detector should avoid direct sunlight and keep away from heat sources.

Fourth, radar life detector

Life Sciences Ralph LifeLocator ® TRx Radar Life Detector

Radar detectors use a new emerging technology - non-contact life detection technology. It uses electromagnetic waves to penetrate shielded media and, like radar, detects vital information, so as to achieve the goal of finding survivors. It detects various micro-motions caused by human life activities, and obtains information on breathing and heartbeats, thereby recognizing the presence or absence of living organisms.

The Radar Life Detector is a combination of ultra-wide spectrum radar technology and biomedical engineering technology. It has a strong penetration capability and can detect life characteristics such as breathing and body movement of the buried living body, and can accurately measure the distance of the buried living body. Depth, with strong anti-interference ability. Compared with optical, infrared and audio detection technologies, it is not affected by ambient temperature, hot objects and sound interference, and has a wide range of application prospects. The radar life detector ( shown in Fig. 4-2-20 ) uses ultra-wideband technology. When searching for survivors trapped in the rubble, it penetrates 4m to 6m of concrete , detecting 20m distance and 216m3 of space. Weak breathing and movement , the specific depth of penetration depends on the surface of the material at the scene, ideally up to 10m or more, but its detection signal can not penetrate the metal barrier. The radar life detector is not affected by other wireless devices and does not affect other wireless devices. It itself transmits the detection results to the controller in the hands of rescue personnel through wireless transmission. Radar life detector signal power is less than 1% of mobile phones , and it is very safe. No wires and probes are needed for use, drilling and waterproofing are not required, and it is not affected by the weather. Radar life detectors can be used simultaneously by multiple systems. It is currently the most advanced life detector in the world.

1 . working principle

The radar life detector works based on the principle of electromagnetic wave modulation. The detector's transmitter ( TX ) continuously emits a radio frequency signal in the direction of possible survivors. The signal is modulated by the motion of buried survivors and reflected. come back. The chest movements caused by breathing and heartbeat have been able to produce enough signal to modulate the detection of the device. The modulated signal is received by the receiver ( PX ) and demodulated again and transmitted to the computer for further analysis. The modulated content of the preprocessed signal is converted into a spectrum and displayed on a measuring computer.

2 . Performance requirements

1 The center frequency is 270MHz to 500MHz .

The time window is 1ns to 5000ns .

3 The minimum time resolution is ≤ 10ps .

4 Sensitivity : -70dB to -110dB .

5 measurable distance: free space: 30m . Depth: 10m .

6 distance resolution up to 100mm .

7 operating temperature range: -20 °C ~ 40 °C .

8 Weight : ≤ 10kg , including battery weight.

9 continuous working hours: ≥ 4h .

3 . Maintenance, maintenance and preservation

The maintenance, maintenance, and preservation of radar life detectors can be performed with reference to the requirements of other life detectors.

This article was edited and compiled by China Rescue Equipment Network. Please indicate the link address.