Basic Structure of Electromagnetic Shielding Rooms:

(1) Electromagnetic shielding rooms typically use cold-rolled steel plates or stainless steel plates as the main shielding material. This includes the six-sided shell, doors, windows, and other building elements, which require a tight electromagnetic seal. Corresponding shielding treatments are also applied to all in-and-out pipelines to block electromagnetic radiation from entering or exiting.

　  (2) Electromagnetic shielding rooms are categorized into three types: steel plate assembled, steel plate welded, and copper mesh. The assembled type is constructed from 1.2mm steel plates, cut into modules with walls of 100mm thickness, and assembled together. It has a simple production and installation process, making it suitable for small areas and projects with lower shielding performance requirements. It can be disassembled and relocated, but its shielding effectiveness will significantly decrease after relocation. The welded steel plate type shielding room is made by welding 1.2mm cold-rolled steel plates to a skeletal frame, offering high shielding effectiveness and compatibility with various sizes, and is the primary form of electromagnetic shielding rooms. The copper mesh type is used for simple projects with lower shielding performance requirements.

2. The primary function of an electromagnetic shielding room:

(1) Isolate external electromagnetic interference to ensure the normal operation of indoor electronic and electrical equipment. Particularly in the measurement and testing of electronic components and electrical equipment, use an electromagnetic shielding room (or a dark room) to simulate an ideal electromagnetic environment, thereby enhancing the accuracy of test results.

(2) Block the spread of indoor electromagnetic radiation to the outside. Strong electromagnetic radiation sources should be shielded and isolated to prevent interference with the normal operation of other electronic and electrical equipment, and even to protect the health of staff.

(3) Prevent information leakage from electronic communication devices to ensure information security. Electronic communication signals are transmitted to the outside world in the form of electromagnetic radiation (i.e., TEMPEST phenomenon). An electromagnetic shielding room is an effective measure to ensure information security.

3. Basic Components of an Electromagnetic Shielding Room:

(1) Enclosure: Taking the steel plate welded electromagnetic shielding room as an example. It includes six-sided skeletal framework and cold-rolled steel plates. The skeletal framework is made of channel steel and square tubes welded together, with material specifications determined by the size of the shielding room. The ground beam (ground girder) should be insulated from the ground. The thickness of the cold-rolled steel plate for the walls is 1.5mm, which is first pre-fabricated into modules in the workshop and then welded to the inside of the skeletal framework. All welding is done using CO2 shielded welding, with continuous full welding and leakage detection using special equipment to prevent wave leakage. All steel enclosures must undergo proper anti-corrosion treatment.

　　(2) Electromagnetic Shielding Door: The electromagnetic shielding door is the only moving component of the shielding room and a crucial factor in its overall shielding effectiveness. It has a high technical content, uses special materials, and involves an extremely complex process with a total of 26 steps. There are two main types of electromagnetic shielding doors: hinged sliding doors and sliding doors, each available in manual, electric, and fully automatic forms. Considering stability and cost-performance, the manual sliding hinged door (standard door: 1900mm x 800mm) is the top choice. Elastic shielding strips should be installed at the connection points between the door and the door frame.

(3) Honeycomb Ventilation Waveguide Windows: Ventilation and air exchange, as well as air regulation, are essential facilities in shielded rooms. The honeycomb waveguide windows are composed of hexagonal steel waveguides with a side spacing of 5mm. These waveguides do not obstruct air flow but effectively block electromagnetic radiation. Currently, full-welded honeycomb waveguide windows of the specification 300mm x 300mm x 50mm are predominantly used, with insertion loss of 150KHz to 1GHz reaching or exceeding 100dB, fully meeting the requirements of the "Regulations." Shielded rooms are equipped with the appropriate number of waveguide windows based on their size, which are used for intake, exhaust, and pressure relief.

(4) Power and Signal Filtering: Conductors such as power lines and communication signal lines entering the shielded room carry conducted electromagnetic interference. Appropriate filters must be used to remove it. Filters are passive bidirectional networks composed of passive components (inductors, capacitors). Their main performance parameters include cutoff frequency (low-pass, high-pass, band-pass, band-stop), insertion loss (band-stop attenuation), and the filter performance depends on the filter order (number of filter elements), filter structure type (single capacitor type C, single inductor type L, π-type), etc.

(5) Waveguide: All non-conductive pipelines entering the shielding room, such as fire sprinkler pipes and optical fibers, should pass through a waveguide. The cutoff principle of the waveguide for electromagnetic radiation is the same as that of the waveguide window.

(6) Indoor Electrical and Renovation: Includes pipe routing, electrical distribution boxes, lighting, power outlets, ceiling installation, wall decoration, and anti-static flooring. To ensure the stable operation of the shielding room, electrical and renovation materials must be selected from fire-resistant, moisture-proof, and environmentally friendly products that meet national standards.

4. Issues related to electromagnetic shielding room projects:

(1) Air Conditioning System: The air conditioning system for shielded rooms can be configured according to actual conditions. If central air conditioning is available, it can be directly connected via waveguide windows or installed separately. All air conditioning power cables, control signal lines for indoor and outdoor units, and water/gas pipes must undergo corresponding shielding treatment.

(2) Fire Alarm System: The electromagnetic shielding room should be equipped with a fire alarm system. The alarm signal lines and related control signals should also be filtered separately. Generally, a smoke detection alarm signal line is configured.

(3) Grounding System: Due to minor leakage during operation (related to the filter's operating characteristics), the grounding requirement for the shielding room is extremely high. A single-point grounding is required, which is related to geological factors, with a grounding resistance ≤ 1Ω. A dedicated grounding wire of 10m² is mandatory.

(4) Power System: The power supply for the shielding room is typically configured with equipment power, air conditioning lighting auxiliary power as needed. Due to a certain amount of leakage in the housing during operation, the power supply for the protective room cannot pass through a leakage protector.

(5) Isolation: Communication elements rooms in civil and national defense command centers all involve vibration isolation projects, which have a close relationship with electromagnetic pulse protection rooms in terms of cross-construction. Vibration isolation is categorized into standard and simple isolation.

　　(6) Supply and exhaust ducts: The electromagnetic pulse protection room should be connected to the supply and exhaust ducts, and installation can only take place after the ducts are properly laid.

5. Features:

(1) Easy to assemble and disassemble, featuring strong assembly technology, attractive appearance, and convenient for users to relocate and expand, thus avoiding redundant investment.

(2) Utilizes modular design with high-quality conductive liners between modules, securely fastened with bolts and sealed for reliable performance.

(3) Modules are electrostatically powder-coated for easy installation and a stylish, elegant appearance.

6. Performance Metrics (Efficiency)

Test Frequency Band, Magnetic Field, Electric Field, Plane Wave, Microwave

     10KHz  150KHz  200KHz～50MHz  50MHz～1GHz  1GHz～20GHz   

Shielding Effectiveness ≥70dB ≥80dB ≥90dB ≥95dB ≥90dB

7. Application Range of Products:

This product is a high-performance electromagnetic shielding room, suitable for instruments with high electromagnetic shielding requirements, such as product testing, testing, information security, and units in computer networks, medical, and financial sectors.