The supply air ceiling of the operating room is the core component of the air purification system in the clean operating room, directly affecting the cleanliness of the operating room and the safety of the surgical environment. Its daily maintenance should follow the principles of precision, standardization and regularity. The specific maintenance contents and procedures are as follows: I. Daily Inspection (Daily/Before and After Each Surgery) Visual inspection Check whether the ceiling panel for the supply air is flat, free from deformation and damage, and whether the sealing strips at the connection points are intact to prevent air leakage and affect the air flow organization. Check the cleanliness of the panel surface and promptly wipe off dust and stains with medical non-woven fabric dipped in neutral detergent to prevent accumulated dust from falling and contaminating the surgical area. Operation status check After turning on the purification system, observe whether the air velocity at the air outlet of the supply ceiling is uniform and there is no obvious abnormal noise (such as abnormal noise from the fan or panel vibration noise). Check the reading of the differential pressure gauge to ensure that the pressure difference between the operating room and the

The replacement cycle of the filters on the supply air ceiling of the operating room should be comprehensively determined based on the type of filter, the usage frequency of the operating room, the environmental dust load and the pressure difference monitoring data. The specific standards are as follows: Primary filter The regular replacement cycle is 1 to 3 months. If the average daily number of surgeries in the operating room is high, the amount of dust in the surrounding environment is large, or the reading of the differential pressure gauge reaches twice the initial differential pressure, it needs to be replaced immediately. After each operation, large particles of dust on the surface can be cleaned with a vacuum cleaner to extend the service life. Medium-efficiency filter The regular replacement cycle is 3 to 6 months. As a “pre-protection” for high-efficiency filters, it needs to be replaced in advance if there is a significant decrease in air volume, severe dust accumulation at the air outlet, or excessive pressure difference. High-efficiency filter The regular replacement cycle is 1 to 2 years. This is the core component of air purification in clean operating rooms, and the pressure difference monitoring data serves as the

Laminar flow sampling carts (also known as clean sampling carts) are mobile local clean environment equipment. Their core is to generate unidirectional clean air flow through a high-efficiency filtration system, creating a sterile and dust-free clean space in the sampling operation area. This prevents samples from being contaminated by environmental microorganisms and particles, while also protecting the safety of operators and the environment. Its application fields are highly focused on scenarios with extremely high requirements for sample purity, experimental accuracy, and production compliance. The core application fields and detailed scenarios are as follows: I. Pharmaceutical and Biopharmaceutical Industry (Core Application Areas) As a key piece of equipment for GMP compliance requirements in the pharmaceutical industry, laminar flow sampling vehicles are an “essential tool” in the production and inspection processes of drugs, mainly used to prevent deviations in inspection results or batch nonconformity of products caused by sample contamination. Pharmaceutical production process: Sampling of raw materials, intermediates and finished products (such as raw material powder, oral liquid preparations, tablets/capsules, sterile injections, etc.) to ensure that the sampling process complies with GMP (Good Manufacturing Practice) requirements and prevent environmental impurities from mixing into the samples. Biopharmaceutical process: Sampling of biological reagents, vaccines,

The core working logic of air purification and disinfection machines is “first purify particulate matter and harmful gases, and then kill microorganisms and bacteria”. Different devices will combine multiple technologies to achieve functions. The mainstream working principles can be divided into two major categories: purification technology and disinfection technology, as follows: I. Core Purification Technology (Removal of Particulate Matter and Harmful Gases) This type of technology mainly addresses common air pollution problems such as dust, hair, formaldehyde and odors. High-efficiency filtration technology (HEPA filter filtration) is the core technology of air purification, with the mainstream being H13/H14 grade HEPA filters. Its filter screen is made of superfine glass fibers interwoven, with pore diameters as low as 0.3 microns. Through interception, inertial collision, diffusion adsorption and other effects, it can capture fine particles such as PM2.5, pollen, dust mite excrement and pet dander in the air, and the filtration efficiency can reach over 99.97%. Filters are usually of composite structure, from the outside to the inside, they are coarse filters (for intercepting hair and large dust particles), HEPA filters (for intercepting fine particles), and activated carbon filters (for adsorbing harmful gases). Activated carbon adsorption technology: Activated carbon has a large number

The air purification and disinfection machine is a device that integrates air purification and sterilization and disinfection functions. With its comprehensive treatment capabilities for particulate matter, harmful gases, and microorganisms, it is widely used in multiple fields such as medical and health care, public buildings, industrial production, and family life. The specific classification and application scenarios are as follows 1. Medical and health care field This is one of the core application scenarios of air purification and disinfection machines, with extremely high requirements for the sterilization efficiency and cleanliness level of the equipment. Hospital departments: operating rooms, icus, neonatal wards, fever clinics, infectious disease wards, etc., can effectively remove bacteria, viruses (such as influenza virus, novel coronavirus), and fungal spores in the air, reducing the risk of cross-infection. General wards and outpatient clinics are used to improve the medical environment and reduce the infection probability for both patients and medical staff. Affiliated areas of medical institutions: pharmacies, laboratories, sterile wards, and temporary storage rooms for medical waste, to prevent the spread of bacteria and contamination of drugs and samples. Other medical scenarios: community clinics, dental clinics, and vaccination sites provide clean and safe treatment Spaces for both medical staff and

Laminar flow sampling vehicles are specialized equipment that provide a local 100-level clean environment. Through high-efficiency filtration and laminar flow air supply technology, they effectively reduce the risk of cross-contamination during sampling and the sampling process. They are widely used in fields with strict cleanliness requirements such as pharmaceuticals, biological products, food testing, and medical devices. I. Daily Application Scenarios and Operation Norms 1. Core application scenarios Pharmaceutical industry: Sampling of intermediate products for active pharmaceutical ingredients and preparations, and retention of finished products to ensure that the samples are not contaminated by environmental microorganisms and particulate matter, and meet the requirements of GMP (Good Manufacturing Practice for Drugs). Biological laboratory: Packaging and sampling of cell culture media and strain samples to prevent the invasion of miscellaneous bacteria and affect experimental results. Food testing: Sample collection and pretreatment of sterile food and health products to ensure the accuracy of testing data. Medical devices: Sampling and random inspection of sterile devices to prevent quality misjudgment caused by sample contamination. 2. Standard operating procedures Check before startup Make sure the equipment is placed stably, the power cord is firmly connected, and there is no damage or aging. Check that the outlet of

The construction cost of the negative pressure weighing room is in the medium to high range, while the maintenance cost is relatively controllable. The overall cost is directly related to the equipment specifications, technical configuration, and usage frequency. Specifically, it can be broken down into two parts: I. Construction Cost: The initial investment is relatively high, and there are three core influencing factors The hardware configuration of the equipment determines the basic cost The core components of the negative pressure weighing chamber include high-efficiency filtration systems (HEPA/ULPA), fan units, airflow control systems, differential pressure monitoring devices, stainless steel operation chambers, etc. The precision and quality of these components directly increase the cost. Conventional small and medium-sized weighing rooms (suitable for small-batch raw material weighing in pharmaceutical factories) : The construction cost is usually between tens of thousands and hundreds of thousands of yuan. Large-scale customized equipment (suitable for highly active materials and multi-station operation, and must comply with EU GMP/US FDA standards) : The cost can reach several hundred thousand yuan, with the main differences lying in additional configurations such as sealing performance, intelligent control systems, and explosion-proof design. The cost of installation and compliance certification cannot be ignored The

The negative pressure weighing chamber is a core specialized equipment for the weighing process of raw materials, excipients and intermediates in pharmaceutical factories. Its significance lies in four core dimensions: personnel safety protection, material purity guarantee, production environment control and compliance compliance. It is a key facility for pharmaceutical production to meet GMP (Good Manufacturing Practice) requirements. Ensure the occupational health and safety of operators In the process of pharmaceutical weighing, the active pharmaceutical ingredients and excipients are mostly in fine powder form, and some materials also have toxicity, corrosiveness, allergenicity or pharmacological activity. The negative pressure weighing chamber forms a stable unidirectional negative pressure airflow through an internal fan, making the indoor air pressure lower than that outdoors. The material dust will be quickly captured by the airflow and filtered through high-efficiency filters (HEPA/ULPA) to prevent the dust from escaping and spreading into the production workshop. This effectively prevents operators from inhaling harmful dust from the root and reduces the risk of occupational exposure. Prevent cross-contamination of materials and ensure the purity of drugs Pharmaceutical production has extremely high requirements for purity. If dust from different batches and types of materials cross-contaminates, it will directly affect the quality of

Both the negative pressure weighing chamber and the laminar flow hood are core equipment in the purification field, but their core functions, airflow principles, and application scenarios are significantly different. The following is a professional analysis from three aspects: core definition, key differences, and applicable scenarios, which is suitable for formal scenarios such as the promotion of Bailun Purification business and technical communication. The content is precise and easy to be applied in practice I. Core Definition (Precise Refinement, Suitable for Professional Communication) Negative pressure weighing chamber: Also known as weighing hood, it is a local negative pressure purification device. Through directional airflow design, it “locks” dust, harmful gases and other pollutants in the operation area inside, preventing them from spreading to the external environment. At the same time, it provides a clean operation space inside, meeting the dual demands of “pollution control” and “local cleanliness”. Laminar flow hood: The full name is “vertical/horizontal laminar flow clean hood”, which is a local positive pressure purification device. It generates uniform clean air flow through high-efficiency filtration (HEPA/ULPA) to cover the target area and prevent dust, microorganisms and other pollutants from the external environment from entering. Its core function is to “create

Based on the practical operation standards of the purification equipment industry and the years of project experience of Bailun Purification, the following systematically sorts out the precautions for negative pressure weighing chambers and laminar flow hoods from two aspects: core installation requirements and key maintenance points. It takes into account both professionalism and practicality to help the equipment operate stably and extend its service life I. Installation Precautions (Disassembly by equipment) (1) Negative Pressure Weighing Chamber: Emphasizing “sealing performance + pressure difference stability + compliance” Installation environment requirements The placement area should be flat and solid, with a ground load-bearing capacity of no less than 500kg/㎡ (to avoid vibration during equipment operation), and a maintenance space of no less than 80cm should be reserved around it (to facilitate the inspection and repair of filters, fans and other components). Stay away from workshop doors and Windows, air outlets and pedestrian passages to prevent external air flow from interfering with the negative pressure balance and avoid cross-contamination of dust. Sealing and structural installation The connection points between the box body and the floor and wall should be filled with sealant (such as silicone sealant) to ensure there are no gaps (gaps will

The core differences in the working principles between VHP pass box and DOP pass box The essential difference in the working principle between the VHP transfer window and the DOP transfer window lies in that the VHP transfer window takes “gas sterilization” as its core to achieve aseptic material transfer. The DOP transfer window, with “HEPA filtration + filter leak detection” at its core, realizes the transfer of clean materials and the verification of purification effects. The specific principle is decomposed as follows: I. Working Principle of VHP Transfer Window (Core Logic of Aseptic) 1. Core objective Through the strong oxidizing property of hydrogen peroxide (VHP) gas, microorganisms (bacteria, viruses, spores, etc.) on the surface of materials are killed, achieving aseptic material transportation and blocking cross-contamination of microorganisms. 2. Key technical principles (1) VHP gas generation and diffusion The equipment is equipped with an internal VHP generator (commonly vaporization type/atomization type), which heats and vaporizes or atomizes high-concentration hydrogen peroxide solution (usually 30%-50%) to form high-purity VHP gas. VHP gas diffuses in the sealed transfer window cavity and forms a circulating airflow through the fan to ensure that the gas evenly covers the surface of the material and every corner

The air velocity of the DOP transfer window is controlled in two scenarios, mainly based on the cleanliness level and functional positioning: the laminar flow surface air velocity is 0.36-0.54 m/s, and the air shower nozzle air velocity is ≥20 m/s. Classification and control standards for wind speed Wind speed type Control range Applicable scenarios Basis and Requirements Laminar flow surface wind speed 0.36-0.54 m/s (commonly 0.4-0.5 m/s) Self-cleaning DOP transfer window, high-efficiency filter air outlet Meet ISO Class 5 cleanliness; JG/T 382-2012 requires ≥0.36 m/s and fluctuation ≤0.2 m/s Air shower nozzle wind speed ≥20 m/s (commonly 20-25 m/s) DOP transfer window with air nozzle According to JG/T 382-2012 and T/NAHIEN 111-2024, the central wind speed at the nozzle of the B3 type air shower transfer window shall not be less than 20 m/s Key points of control Laminar flow surface air velocity: Measured by the average air velocity at the outlet of the high-efficiency filter, if it is too low, it will lead to a decrease in cleanliness; if it is too high, it is prone to turbulence and increased energy consumption. Regular detection is required and the filter element should be replaced when the resistance exceeds the