Aseptic Laboratory Planning, Design, and Construction Solutions

　　Aseptic laboratories are primarily used for research in biochemistry, biomedicine, microbiology, animal experimentation, genetic engineering, and biopharmaceuticals, and are collectively referred to as cleanrooms.

　　I. Sterile Laboratory Planning Scheme and Floor Plan Layout

　　Composition: The aseptic laboratory consists of six sections: the preparation room, the washing room, the sterilization room, the aseptic room, the constant-temperature incubation room, and the general laboratory. A common feature of these rooms is that their floors and walls are required to be smooth and durable, and their furnishings and equipment are kept simple to facilitate cleaning.

　　Requirements for the inner and outer rooms: A sterile laboratory should comprise an inner room and an outer room, with the inner room serving as the aseptic chamber and the outer room functioning as a buffer zone. The floor area of all rooms should not be excessively large, and the ceiling height should not be too high, to facilitate air sterilization.

　　Safety Requirements: Sterile laboratories and biosafety laboratories must ensure the safety of personnel, the environment, waste, and samples, operate safely and sustainably over the long term, and provide laboratory personnel with a comfortable and conducive working environment.

　　II. Basic Requirements and Configuration Standards for Sterile Laboratories

　　1. Preparation Room—The preparation room is used for preparing culture media and handling samples, among other tasks.

　　The room is equipped with reagent cabinets, dedicated storage cabinets for apparatus and materials, power outlets, an electric hot plate, a refrigerator, laboratory benches, and plumbing.

　　2. Washing Room—The washing room is used for cleaning glassware and other utensils.

　　Since used utensils are often contaminated by microorganisms, pathogenic microbes may also be present. Therefore, where conditions permit, a washing room should be provided. The room should be equipped with a heater, a steamer, basins and buckets for washing dishes, as well as various bottle brushes, soap, laundry detergent, and stain‑removing powder.

　　3. Sterilization Room—The sterilization room is primarily used for sterilizing culture media and various laboratory utensils.

　　The laboratory shall be equipped with sterilization equipment and facilities, such as an oven and an autoclave.

　　4. Sterile Room—A dedicated laboratory for systematic inoculation and strain purification procedures.

　　Aseptic chambers, also known as inoculation rooms, are essential in microbiological work, where the inoculation and transfer of microbial strains constitute a key procedure. The hallmark of this operation is ensuring the purity of the strain and preventing contamination by extraneous microorganisms. In typical ambient air, the presence of numerous particulates and miscellaneous microbes can readily lead to contamination, significantly interfering with inoculation activities.

　　III. Main Components of Sterile Laboratory Construction and Renovation

　　1. Construction of well-sealed enclosures;

　　2. Floor treatment for easy cleaning and hygiene;

　　3. High-quality air conditioning and circulating purification filtration system;

　　4. A sensitive cleanliness detection and control system;

　　5. Design a well-optimized pneumatic pressure isolation system.

　　IV. Aseptic Laboratory Design Plan

　　1. Overall Structure of the Sterile Laboratory

　　All structures in the design of a sterile laboratory shall be robust and durable, easy to maintain and clean, and equipped with features that prevent contamination of food, food-contact surfaces, and primary packaging materials—such as the intrusion, habitation, or reproduction of harmful organisms.

　　To prevent cross-contamination, separate access routes for personnel and material transport shall be provided. The personnel access route must strictly comply with cleanroom access requirements, and each route shall be equipped with air curtains, bi-directional spring‑loaded doors, and electronic insect (fly and mosquito) control devices, among other pest‑control measures.

　　All gaps around service penetrations, doors, windows, and ventilation ducts must be completely sealed, and all windows, vents, and fan openings shall be fitted with protective screens.

　　The height of the aseptic laboratory shall meet process and hygiene requirements, as well as the needs for equipment installation, maintenance, and upkeep.

　　2. Workbench in the aseptic laboratory

　　The aseptic work area shall be equipped with an aseptic workstation or, alternatively, a clean bench, and it must be positioned away from the door.

　　The flooring in a sterile laboratory shall be constructed from non‑toxic, slip‑resistant, impermeable, non‑absorbent, crack‑free materials that are easy to clean and disinfect (such as acid‑resistant tiles, terrazzo, or concrete). The floor should have an appropriate slope, preferably between 1.0% and 1.5%.

　　3. Roof and Ceiling of the Sterile Laboratory

　　Roofs and ceilings shall be finished with light-colored materials that are non‑absorbent, smooth‑surfaced, non‑toxic, mold‑resistant, corrosion‑resistant, and easy to clean.

　　No auxiliary pipelines for steam, water, electricity, or other utilities shall be installed above food or food-contact surfaces to prevent the ingress of dust, condensate, or other contaminants.

　　4. Walls and Doors/Windows of the Sterile Laboratory

　　The walls of the aseptic laboratory shall be constructed from non‑toxic, non‑absorbent, impermeable, mold‑resistant, smooth, and easily cleanable light‑colored materials, with the finish extending to the ceiling.

　　All door and window assemblies shall be equipped with weather‑resistant, moisture‑proof, and easy‑to‑clean sealed frames.

　　The aseptic laboratory shall be provided with adequate natural daylight or artificial lighting; the mixed illuminance on work surfaces in processing areas shall not be less than 300 lux, and in batching and filling workshops it shall not be less than 800 lux.

　　5. Air Treatment and Purification Facilities for Sterile Laboratories

　　Aseptic laboratories must be equipped with effective ventilation systems, with airflow directed from clean areas to non‑clean areas. When mechanical ventilation is used, the air exchange rate shall be greater than three times per hour.

　　The temperature in a sterile laboratory should be maintained between 15 and 27°C, with humidity preferably kept below 50%.

　　The entrance to the aseptic laboratory shall be equipped with separate purification facilities for personnel and materials.

　　V. Management and Disinfection of the Aseptic Laboratory

　　The interior design and disinfection requirements of a sterile laboratory are extremely stringent:

　　The aseptic laboratory should, before and after each use, wipe the work surfaces and any potentially contaminated dead corners with a 0.1% benzalkonium bromide solution or a 2% formaldehyde solution, mop the floor with a damp cloth, turn on the sterile air filter and the laminar flow hood for 30 minutes, and irradiate with a UV germicidal lamp for 1 hour.

　　After washing their hands with soap, operators enter the buffer room to change into slippers, wipe their hands with 75% alcohol swabs, and don on work uniforms, caps, and masks. They remove the kraft paper and outer packaging from the required items, transfer them into the operating room through the pass-through window, then immerse their hands in a 0.1% benzalkonium chloride solution before entering the operating room. All procedures are performed within the alcohol (or gas lamp) flame zone, where the flame height is maintained at 3–5 cm.

　　Operators must not use their mouths to directly suck or blow through pipettes, in order to prevent pathogenic microorganisms from infecting the operator and to avoid contamination of the test sample by oral flora.

　　Disinfect the surface of the test sample: for ampoules, first score the glass with a grinding wheel, then wipe with a 2% iodine‑alcohol swab, followed by a 75% ethanol swab; allow to dry. Alternatively, the sample may be immersed in a disinfectant solution for sterilization.

　　If aspiration is required, draw sterile air into the syringe while holding it over a flame.

　　During aseptic procedures, avoid large or rapid movements and dragging to prevent stirring up airborne particulates.

　　All materials used, such as culture media and diluents, must be prepared and subjected to moist heat sterilization at 121°C for 30 minutes. Pipettes, petri dishes, and other such items should be washed, dried, and packaged before being sterilized by dry heat at 160°C for 2 hours prior to use.

　　Aseptic laboratories are typically located within microbiology facilities, and both indoor and outdoor ventilation systems must be equipped with air filtration devices. Once a sterile environment and sterile materials have been established, maintaining sterility is essential for conducting research on specific, well‑characterized microorganisms. Consequently, microbial control capability and the stability of that control are the core acceptance criteria for aseptic rooms. The industry‑standard acceptance limits stipulate that in a Class 100 cleanroom, the average number of colony‑forming units on agar plates should not exceed one; in a Class 10,000 cleanroom, the average should not exceed three. In addition to these standard requirements, regular maintenance and upkeep are indispensable. Only through judicious material selection during construction, appropriate purification levels, and consistent long‑term management and maintenance can an aseptic laboratory fulfill its intended purpose.