Sealant strip replacement criteria (General + Special for VHP models) I. Visual appearance inspection (Quick daily pre-shift judgment) Any one of the following conditions met suggests replacement is recommended: Hardening, loss of elasticity Press the rubber strip with your finger, and it won’t rebound quickly when released; the pressed area is permanently concave; it feels hard and lacks the soft rubber texture, and the effect is more obvious at low temperatures. Cracking, fracture, chipping Minor fine lines and cracks appear on the surface of the rubber strip; the edges and door corners are the most prone to breakage; VHP models may develop fine cracks due to long-term oxidation. Color change, powdering, chipping The silicone strip turns yellow, white, or gray; when rubbed with your hand, white powder falls off; VHP hydrogen peroxide corrosion easily causes powdering. Detachment, falling off, displacement The rubber strip separates from the door frame, local warping, or the entire strip becomes loose; the door cannot fully close and fit the cavity. Deformation, flattening, permanent inability to recover Permanent flattening occurs due to long-term closing pressure, and there are gaps at the door seam. Mold growth, blackening, bacterial colonies The stubborn mold stains cannot be removed by

1. Core structure differences     Partitioned efficient filter: Built-in aluminum foil / paper partition to support the filter paper, with a large gap between the filter layer folds, overall thickness is thick (150/220mm), and the filter material support strength is high DOP liquid channel efficient filter: No partition, hot melt adhesive strips, lightweight model (66/93mm), the filter core is more compact, and the wind resistance is lower 2. Edge frame sealing  Partitioned efficient filter: Flat edge frame, sealed by foam sealing strips; disassembly may cause frame leakage; DOP leak detection has blind areas DOP liquid channel efficient filter: Four-sided U-shaped liquid channel, matched with blue jelly elastic glue for immersion sealing; seamless sealing, can conduct complete DOP scanning leak detection for the entire machine, in line with GMP audit requirements 3. Performance advantages and disadvantages comparison (short sentences with pictures used) Partitioned efficient filter ✅ Advantages Partitioned support, no deformation under high wind pressure, solid structure Large filter layer expansion area, high dust capacity, long replacement cycle Wide filter gap, convenient manual leak detection and repair Aluminum partition model suitable for large air volume continuous operation ❌ Shortcomings Flat sealing strips have average sealing performance, prone to side leakage

A Complete Maintenance Cost Solution for Air Distribution Ceiling By implementing measures in six key areas – front-end protection, consumable management, manual burden reduction, energy consumption optimization, compliance control, and equipment selection – this solution can not only extend the lifespan of the filter but also reduce long-term costs such as labor, testing, and electricity expenses. 1. Multi-level Front-End Filtration: Significantly extends the lifespan of the HEPA filter (the core cost reduction method) The high-efficiency filter is the largest consumable expense. Reducing the replacement frequency directly saves a lot of money. The initial-stage G4 and intermediate-stage F8/F9 filters on the air conditioning unit end provide double interception, reducing the dust content in the incoming air of the air distribution ceiling. An independent built-in intermediate-stage filter is added to the air distribution ceiling inlet to block pipe rust and insulation debris. Strictly replace the initial and intermediate-stage filters based on pressure difference, not waiting until they are clogged before replacing, avoiding direct impact of dust on the high-efficiency filter after penetration. A wind shower room and a material shower room are added at the entrance of the dust-free workshop to reduce dust brought in by personnel and materials, reducing the load

The safety types of ultra-clean workstations are mainly classified based on the pressure state, protection objects, and air flow operation logic. The core difference lies in the protection scope (whether it only protects the samples or also takes into account the personnel and the environment). This is the core basis for selecting laboratory safety types. Currently, the mainstream safety types are divided into three categories, as follows: 1. Positive pressure clean type (protection only for samples, no protection for personnel or environment) The positive pressure clean type is the basic model of ultra-clean workstations. The overall cavity is in a positive pressure state, with internal air pressure higher than the external environment. Its core function is to isolate external contaminants from entering the operation area, providing sterile and dust-free protection only for the experimental samples, but it does not have the ability to prevent internal contaminants from spilling out. It is the most commonly used basic safety type in laboratories. (1) Vertical flow positive pressure ultra-clean workstation The air flow passes through the HEPA filter on the top of the equipment and is filtered before being blown downward in a uniform laminar flow over the entire operation surface, and then

Daily Maintenance Key Details for Transfer Windows (General, UV Type, VHP Type, GMP Compliance Focus) I. General Details for All Types of Transfer Windows 1. Cleaning Operation Details Only use dust-free cloths and dust-free papers for cleaning. Ordinary rags, steel wool, and scouring pads are prohibited. They can easily scratch the stainless steel inner walls and observation windows, and the scratches can accumulate dirt and breed microorganisms. Cleaning Agents: 75% ethanol, purified water, neutral cleaning agent; strictly prohibit 84, hypochlorous acid sodium, strong acids and strong bases. Long-term use will corrode the stainless steel and cause rust spots. VHP models corrode even faster. Cleaning Order: From the high-cleanliness side to the low-cleanliness side, from top to bottom. Avoid secondary dust pollution from the door gap, sealing strip groove, hinge bottom, and cavity edge corners. All must be wiped one by one. Residual liquid will crystallize and age the rubber strip. Do not directly spray water into the cavity. Before cleaning the electric control box, fan, sensor, and wiring, use a dust cover to shield to prevent water ingress and short circuits, and prevent probe fouling and malfunction. After cleaning, the cavity must be dried. No water stains should be left.

The standard process for reviewing and verifying the inspection records of the negative pressure weighing room (GMP Level 3 review) is divided into three levels: operator self-inspection, team leader on-duty review, and QA/equipment staff regular spot-check verification. Each level has clear verification points, judgment criteria, and handling methods for non-compliance, ensuring the records are accurate, complete, and auditable. 1. Level 1 Review: Operator Self-Inspection (Immediate execution upon completion, the first checkpoint) Verification steps and verification contents Verification of basic information completeness Check if all items such as equipment number, date, shift, start-up and shutdown time, and operator signature are filled in, with no blank spaces; if the equipment is idle on the same day, note “This shift did not use the equipment, it is in standby mode”. Self-check of quantitative parameters authenticity Observe the differential pressure gauge and wind speed display again: Check if the negative pressure and wind speed values in the record table are consistent with the current reading of the instrument; if the values exceed the standard range (＜-15Pa or ＞-30Pa, wind speed ＜0.35/＞0.45m/s), it must be noted in the abnormal column, and “normal” cannot be only checked. Item-by-item verification of qualitative items Verify each item one

Various daily physical disinfection methods for transfer windows and corresponding applicable scenarios 1. Ultraviolet UV-C irradiation (the most mainstream and universally applicable daily disinfection method across the industry) Applicable scenarios Electronic dust-free workshops (100,000-level, 10,000-level) Daily transfer of lithium batteries, optics, plastics, hardware components, packaging consumables, rapid killing of floating bacteria on the surface of materials, meeting routine clean control requirements. Food clean packaging workshop, daily chemical-free cleaning workshop Intermediate packaging materials, finished products, small tools transfer, no chemical residues, no contamination of products. General hospital laboratory, outpatient pharmacy, general clean operating room Transfer of test samples, medical consumables, small instruments, simple operation, fast disinfection. Non-sterile medical device production clean area Daily entry and exit of parts and testing tools, meeting basic microbial control requirements. Physical laboratories, routine research laboratories Glassware, ordinary samples, experimental consumables circulation and disinfection. Daily pre-treatment of sterile pharmaceuticals / sterile instrument workshops Combined with 75% alcohol wiping for daily basic disinfection. It cannot be used alone as final sterilization. It needs to be regularly combined with VHP fumigation. Unsuitable scenarios Materials stacked multiple layers, materials with many folds and pores; In high-risk spore areas, only ultraviolet cannot achieve sterility. II. FFU laminar flow self-purification blowing

Daily physical disinfection methods for transfer windows (routine in workshops, without chemical agents) 1. UV-C ultraviolet light irradiation (standard equipment, most commonly used) All ordinary interlocking transfer windows come with this feature and are considered a daily standard physical disinfection method. Principle: Short-wave ultraviolet light damages the DNA of bacteria and molds, killing surface microorganisms; Operation: Place the materials in, close the double doors, and irradiate for 15 to 30 minutes; Applicable: Electronic workshops, food, medical devices, laboratories, hospitals for daily material transfer. 2. FFU laminar flow self-cleaning blow-off (specific for laminar transfer windows) Relying on efficient single-directional airflow, it physically removes dust and floating bacteria. Principle: The FFU in the box continuously blows out a clean laminar flow to disperse and filter floating pollutants; Operation: Close the door and turn on the fan for self-cleaning for 10 to 20 minutes, often combined with UV irradiation; Applicable: Hundreds / thousands of grade high-cleanliness electronic, cell rooms, sterile raw material drug workshops. 3. Dry physical dust removal (preliminary pre-treatment cleaning) It is an auxiliary physical disinfection method and helps reduce the microbial base: Dust-free dry cloth wiping Each shift should dry wipe the box body, glass and sealing strips with a

Air shower self-cleaning transfer window with complete installation + standard operating procedures The air shower self-cleaning transfer window (air shower transfer window) is equipped with a fan, high-efficiency filter, blowing nozzle, ultraviolet disinfection, electronic/mechanical double-door interlock. It is used for the transfer of small items between clean areas and non-clean areas, or between different clean levels. It uses high-pressure clean air flow to blow off dust on the surface of the materials and prevent cross-contamination of air flow. It complies with the GB50591 construction specifications for clean rooms. Scene of the installation of the air shower transfer window I. Installation Construction Process (including pre-installation preparation, fixation, wiring, and acceptance) (1) Pre-installation Preparation Positioning and wall hole opening Select an independent logistics partition wall, away from the air shower door, with a wall thickness matching the equipment depth; Hole size: 10-20mm larger than the equipment outer frame to facilitate leveling and sealant application; Wall surface leveling: vertical deviation ≤ 2mm/m, horizontal deviation ≤ 1mm/m. Hollow walls / color steel plate partitions need to be reinforced around to prevent equipment deformation and air leakage. Box opening inspection Check the completeness of the box body, fan, primary / high-efficiency filters, interlock door, sealing

Comparison of Filter Lifespan Differences for Explosion-proof FFU Based on three dimensions: pre-filtering (initial / intermediate efficiency), end-stage high-efficiency HEPA/ULPA (glass fiber, PTFE-coated), and structural style (flat / without partition / V-shaped), combined with lithium battery, chemical, and pharmaceutical explosion-proof conditions, the lifespan differences are explained. I. Classified by level: pre-filter vs end-stage high-efficiency (the largest lifespan gap) 1. Top-of-FFU initial efficiency / pre-filtering net (G3/G4) Material: non-woven fabric, nylon net, metal net Characteristics: Intercepts hair, flocculent substances, large-particle dust, protecting the rear-end high-efficiency Explosion-proof scenarios lifespan: Low-dust pharmaceutical / laboratory: 1-3 months, washable 2-3 times before replacement Lithium battery, solvent workshop: 15-30 days, oil and dust are highly prone to clogging the net Feature: The shortest lifespan, but the lowest cost, is the core consumable for extending the lifespan of the high-efficiency 2. Intermediate-efficiency filter (F5-F9, for new air systems, rarely built-in in FFU) Lifespan: 3-6 months in clean explosion-proof area; 1.5-3 months in high-dust explosion-proof workshop 3. End-stage high-efficiency filter (determines cleanliness, the most expensive) All core consumables of explosion-proof FFU, the lifespan is much longer than the pre-filter, but the difference in filter materials is extremely large. II. Comparison of high-efficiency filter material (the most core lifespan

Audit Control Plan for Accuracy and Completeness of Negative Pressure Weighing Room Inspection Records (Applicable to GMP Audit) This plan is implemented from six dimensions: personnel management, filling norms, on-site control, rechecking and verification, traceability closure, and training assessment, to completely eliminate the problems of omitted filling, false filling, data distortion, and missing records. I. Pre-control: Ensure the authenticity and completeness of records from the source 1. Define job responsibilities and assign them to individuals Operator’s primary responsibility: Pre-checking before startup, observing parameters during operation, confirming cleaning at the end of the shift, filling in immediately during the shift, prohibiting filling after the shift or making up entries the next day. Team leader’s review responsibility: Before each shift ends, check each record item one by one, verify abnormalities and blank items on the spot. QA inspection supervision: Conduct on-site random checks daily, compare real-time equipment parameters with paper records. Equipment administrator’s archiving review: Recycle ledgers weekly, uniformly check for completeness, and hold accountable for missing records. 2. Standardize record forms to prevent omissions Fixed mandatory items in the template: Negative pressure and wind speed must have a numerical filling column, not just a checkmark for normal/abnormal; Each inspection item is

Sealant liquid (jelly-like gel) replacement cycle standard It is divided into two parts: fixed cycle and immediate replacement judgment conditions, which are suitable for different working conditions in pharmaceutical GMP and electronic dust-free workshops: 1. Regular complete replacement cycle (empty the entire tank and replace with new gel) Frequent VHP hydrogen peroxide fumigation of A/B grade sterile areas, operating rooms, P2/P3 laboratories Replace once every 6 months The fumigation of oxidants will accelerate the aging, stratification, and blackening and precipitation of the gel, easily causing leakage of the seal. GMP verification pays special attention to this. General pharmaceutical clean areas, thousand-level/electronic clean workshops, and less fumigation environments Replace the entire tank once every 12 months (1 year) Cleanrooms with low dust, stable temperature, and almost no space sterilization The highest quality silicone-based sealant can be extended to once every 2 years for replacement, but it is not recommended to exceed 2 years Note: Only replenish and do not add (no replacement) Monthly inspection only replenishes the liquid: when the liquid level is below the standard scale, there is a small amount of evaporation loss, directly add the same type of new gel; Do not mix large amounts of new and