1.Layout Arrangement Forms
Corridor-surrounding Type
The peripheral corridor can be windowed or windowless, serving for visiting and equipment placement; duty heating facilities can also be arranged inside. External windows must be double-layer sealed windows.
Inner Corridor Type
Cleanrooms are arranged on the outer perimeter with the corridor located internally. Such corridors generally have a high cleanliness level, even equivalent to that of cleanrooms.
Two-end Type
The clean area is arranged on one side, while quasi-clean areas and auxiliary rooms are set on the other side.
Core Type
To save land use and shorten pipeline routes, the clean area is taken as the core, surrounded by various auxiliary rooms and concealed pipeline spaces on all sides. This layout avoids the impact of outdoor climate on the clean area, reduces cooling and heating energy consumption, and facilitates energy conservation.
2.Personnel Purification Route
To minimize pollution generated by personnel activities during operation, staff must change into clean garments, pass through air showers, take showers and conduct disinfection before entering the clean area. These procedures are collectively referred to as personnel purification.Air supply shall be provided to the clean garment changing rooms in personnel purification areas, maintaining positive pressure relative to entrance rooms and slight positive pressure relative to toilets and shower rooms; toilets and shower rooms shall be kept under negative pressure.
3.Material Purification Route
All articles must undergo purification treatment before being delivered into the clean area, known as material purification.The material purification route shall be separated from the personnel purification route. If personnel and materials have to enter the cleanroom at the same location, dedicated access shall be adopted respectively, with materials undergoing preliminary rough purification first.For sites with discontinuous production lines, intermediate warehouses may be set along the material route. For continuous production lines, straight-through material routes are adopted, with multiple purification and transfer facilities installed as required.In system design, the rough and fine purification sections of material purification rooms will generate large amounts of particulate matter during air blowing, so they shall be maintained at negative pressure or zero pressure relative to the clean area. Negative pressure shall also be maintained towards the entrance direction where pollution risk is high.
4.Pipeline Arrangement
Cleanrooms involve extremely complex pipelines, which are all arranged in concealed forms as follows:
Technical Interlayer
(1) Ceiling Technical Interlayer
Air supply and return ducts occupy the largest cross-section and are prioritized to be arranged at the top of the interlayer, with electrical pipelines placed underneath. If the bottom slab of the interlayer bears sufficient load, filters and exhaust equipment can be installed on it.
(2) Room Technical Interlayer
Compared with ceiling-only interlayers, this form reduces wiring density and interlayer height, and omits technical chutes for return air ducts leading back to the upper interlayer. Return air fans, power equipment and power distribution devices can be arranged in the lower chute. The upper chute of one floor can serve as the lower chute of the floor above.
Technical Chute (Partition Wall)
Horizontal pipelines in upper and lower interlayers are normally converted to vertical pipelines, which are concealed inside technical chutes. Auxiliary equipment unsuitable for placement inside cleanrooms can be installed in such chutes, which can also function as general return air ducts or static pressure boxes, and may be equipped with tubular radiators.Most technical chutes adopt lightweight partitions, allowing flexible adjustment during process modification.
Technical Shaft
Unlike technical chutes which are usually floor-bound, technical shafts run across floors and are permanently integrated into the building structure.As technical shafts connect all floors, the interlayer spaces shall be sealed with materials having fire resistance rating no lower than floor slabs after pipeline installation for fire prevention. Maintenance is conducted floor by floor with fire-rated access doors installed.Where technical interlayers, chutes or shafts directly serve as air ducts, their internal surfaces shall be treated in compliance with cleanroom interior surface requirements.
5.Equipment Room Layout
Air conditioning rooms are preferably arranged close to cleanrooms with large air supply demand to minimize duct routes. Meanwhile, separation between cleanrooms and equipment rooms is required for noise and vibration control, and both factors shall be fully considered.
Structural Separation
Settlement Joint Separation: A settlement joint is arranged between the cleanroom and equipment room for isolation.
Cavity Wall Separation: Where the equipment room is adjacent to the cleanroom, independent partition walls are adopted for each side with a reserved gap in between instead of sharing one wall.
Auxiliary Room Separation: Auxiliary rooms are arranged between the cleanroom and equipment room as a buffer zone.
Decentralized Layout
Roof / Ceiling Layout: Equipment rooms are commonly placed on the top floor roof to stay away from lower cleanrooms. The floor directly below the roof is preferably arranged as auxiliary rooms, management rooms or technical interlayers.
Underground Layout: Equipment rooms are located in the basement.
Independent Building Layout
A standalone equipment building is constructed separately from the cleanroom building and kept in close proximity.Vibration isolation and sound insulation shall be addressed for equipment rooms, with fully waterproofed floors and drainage measures installed.
Vibration Isolation: Vibration isolation measures shall be applied to supports and bases of vibration sources such as fans, motors and water pumps. Where necessary, equipment shall be mounted on concrete slabs supported by vibration-damping materials; the slab weight shall be 2 to 3 times the total equipment weight.
Sound Insulation: In addition to system silencers, large equipment rooms may adopt sound-absorbing wall materials and sound insulation doors. No door shall be opened on the partition wall facing the clean area.
6.Emergency Evacuation
Cleanrooms are highly enclosed buildings, making emergency evacuation a critical issue closely related to the design of air handling and purification systems. Key requirements are as follows:
At least 2 emergency exits shall be provided for each fire compartment or clean area on every production floor; only one exit is permitted if the area is less than 50 ㎡ with fewer than 5 occupants.
Personnel purification entrances shall not be used as evacuation exits, as the winding purification routes hinder rapid outdoor evacuation in case of fire and smoke.
Air shower rooms shall not serve as regular access passages. Interlocked or automatic doors are prone to failure and hinder evacuation. Bypass doors must be installed for air shower rooms, which are mandatory when staff exceed 5 persons. Staff shall use bypass doors instead of air showers when exiting the clean area under normal conditions.
To maintain indoor pressure, doors inside the clean area conventionally open towards higher-pressure rooms, which conflicts with emergency evacuation requirements. To balance daily cleanliness and emergency evacuation needs, doors between clean and non-clean areas, and doors leading from clean areas to the outdoors shall be designed as emergency evacuation doors opening towards the evacuation direction; standalone emergency doors shall follow the same rule.
7.Overview of Cleanroom Architectural Decoration
Cleanroom architectural decoration works cover all works excluding the main structure, external doors and windows, including floor finishing, plastering, door and window works, ceiling works, partition works, coating and painting works, as well as sealing of joints between pipelines, lighting fixtures, air purification equipment, process equipment and building structures.
The importance of cleanroom decoration is reflected in two aspects:
Impact on Overall Performance: Cleanroom materials shall be dust-free and non-dust-accumulative with airtight structures. Decoration quality directly determines the cleaning effect.
Impact on Construction Cost: Cleanrooms are high-cost buildings compared with ordinary office buildings.
Requirements for Decorative Materials
General Requirements：
➤Smooth surface
➤Wear resistance
➤Good thermal insulation
➤Low static electricity generation
➤Moisture-proof and impermeable
➤Good sound absorption
➤Easy processing
➤Low dust adhesion
➤Easy dust removal
➤Cost-effective
Floor Decoration
General Requirements: ①Wear resistance②Chemical resistance (acid, alkali, pharmaceutical)③Anti-static performance④Slip resistance⑤Seamless construction available⑥Easy cleaning
Common Floor Types:
➤Raised Floor: Typical for vertical unidirectional flow cleanrooms. Features: return air accessible from floor, good air permeability, high cost, poor elasticity.
➤Terrazzo Floor: Features: smooth, non-dust-generative, good integrity, washable, anti-static, inelastic.
➤Resin Coating Floor: Inherits terrazzo advantages with wear resistance, good airtightness and elasticity; complex construction. Made of epoxy resin, polyester resin or polyurethane resin mixed with pigments and curing agents; cement mortar base strength shall not be lower than Grade 425.
➤Roll Sheet Floor: Features: smooth, wear-resistant, slightly elastic, non-dust-generative, easy cleaning, simple construction; prone to static electricity and UV aging, easy peeling in large areas due to different thermal expansion coefficients from concrete.
➤Acid-resistant Ceramic Floor: Features: corrosion-resistant but brittle and impact-sensitive; complex construction and high cost. Suitable for corrosion-prone zones with water stop boundaries.
➤FRP Floor: Features: corrosion resistance and good integrity; limited to small-area application due to mismatched thermal expansion coefficients with base structures; fire-retardant grade is required.
Wall Decoration
General Requirements: ①Stain-resistant and easy cleaning②Smooth surface finish③No dust generation upon peeling or damage④Impact resistance⑤Arc or sealed treatment for internal corners
Common Wall Types:
➤High-grade Plastering: Mandatory for cleanroom walls with standard procedures including corner squaring, screed setting, layered leveling, surface trimming and burnishing.
➤Latex Paint: Features: smooth, non-peeling, low cost, non-washable.
Epoxy & Synthetic Resin Paint: Smooth, non-peeling, washable, corrosion-resistant, high construction requirements.
➤Mildew-proof Coating: Smooth, non-peeling, washable and corrosion-resistant.
➤Ceramic Panel: Smooth, corrosion-resistant and easy cleaning; excessive joints, difficult leveling and high construction requirements.
➤Metal Panel: Corrosion-resistant, fireproof, static-free, smooth, easy cleaning, high cost. Materials include epoxy composite aluminum panel, rust-proof aluminum panel, stainless steel and color-coated steel plate. Color-coated steel plate adopts galvanized steel substrate, alkyd resin primer, and thermosetting acrylic / epoxy / polyester resin topcoat.
➤Prefabricated Cleanroom Wall Panel: Widely adopted especially for renovation projects with variable properties by material. Double-layer filled metal panels provide thermal insulation suitable for air-conditioned and constant-temperature environments with high structural strength.Composition: face sheet + core material, selected per design.
➤Face sheet: melamine laminated wood, aluminum alloy plate, steel plate, color steel plate, etc.
➤Core material:
- Rigid polyurethane foam: on-site foaming, excellent thermal insulation; halogenated organophosphorus added as flame retardant, classified as combustible, flame-retardant and non-combustible grades.
- Asbestos calcium silicate board: lightweight calcium carbonate mixed with inorganic fiber and fire retardant, foamed and bonded with PVC resin; good fire resistance, quasi-non-combustible.
- Polystyrene sandwich board: polystyrene insulation sandwiched between steel plates via gluing and pressing; releases irritating gas during combustion, not recommended for high fire-risk areas.
- Rock wool sandwich board: rock wool sandwiched between steel plates, suitable for high fire protection requirements; gypsum board lining required for load-bearing use to avoid deformation.
e. Paper / Aluminum honeycomb board: honeycomb core sandwiched between steel plates; high strength, aluminum honeycomb with superior fire performance.
Ceiling Decoration
General Requirements:
Lightweight ceiling framework with high rigidity and convenient installation. Vibration resistance against falling off is more critical than surface hardness, as ceiling panels are less affected by manual friction but vulnerable to vibration from upper ducts and equipment.
Ceiling Framework Types:
➤Light Steel Keel: Lightweight, low steel consumption; careful joint treatment; inaccessible for maintenance, cannot serve as temporary walkways or load-bearing supports, inconvenient overhaul.
➤Section Steel Keel: Adaptable to air outlet and lamp opening layout; high steel consumption.
➤Aluminum Alloy Keel: Lightest weight; careful joint treatment; inaccessible for maintenance, cannot serve as temporary walkways or load-bearing supports, inconvenient overhaul.
Ceiling Panel Materials
Most wall decorative materials are applicable for ceiling panels; colored plastic panels are also ideal options.
Seam Sealing Materials
General Requirements: ①Excellent sealing performance with proper elasticity②Aging resistance③Fast curing④Single-component preferred⑤Easy application⑥Good adhesion⑦Non-toxic, odorless, color coordinated with decoration
Common Sealant Types:
➤Silicone Rubber: Wide temperature adaptability, good chemical and oil resistance; poor NaOH resistance, prone to mildew. Semi-inorganic polymer elastic material based on siloxane structure.
➤Polyurethane: High hardness, good elasticity and low-temperature performance, oil and ozone resistant; poor water resistance. Synthesized from polyisocyanate and active hydrogen alcohols / amines with curing agents.
➤Synthetic Rubber: Balanced elasticity, chemical resistance, water resistance, oil resistance and durability; mainly nitrile rubber.
Special Requirements
In accordance with Code for Construction and Acceptance of Cleanrooms:
Moisture content of timber used in cleanrooms shall not exceed 16% with no exposed application. High air change rate and low relative humidity may cause cracking, deformation, loosening and dust generation for excessive timber use. Partial application is allowed only with anti-corrosion and moisture-proof treatment.
Waterproof gypsum board is mandatory for ordinary cleanrooms. For biological cleanrooms with frequent water and disinfectant washing, even waterproof gypsum board is prone to moisture deformation and abrasion damage, hence prohibited as ceiling facing material.
8.Principles for Rational Layout of Dust-Free Cleanrooms
Cleanroom architectural layout is closely associated with purification and air conditioning system design. Designers shall coordinate architectural layout and system arrangement, and put forward layout requirements to optimize overall functions.A dust-free cleanroom generally consists of clean area, quasi-clean area and auxiliary area. Layout design shall follow the key points below:
Plane layout forms: corridor-surrounding type, inner corridor type, two-end type and core type.
Personnel purification route: staff shall change into dust-free garments and pass through air shower disinfection before entering clean areas; air supply is required for garment changing rooms.
Material purification route: all materials require purification treatment before entry; routes shall be separated from personnel routes or adopt dedicated access. Purification transfer facilities and intermediate warehouses can be installed as needed.
Pipeline arrangement: complex pipelines in dust-free rooms adopt concealed layout including ceiling technical interlayer, room technical interlayer, technical chute and technical shaft. All structures used as air ducts shall meet cleanroom interior surface standards.
Equipment room layout: air conditioning rooms are preferably close to high-air-volume cleanrooms for shortest duct routes, while separated for noise and vibration control. Separation and layout forms include settlement joint separation, cavity wall separation, auxiliary room separation, rooftop layout, underground layout and independent building layout. Vibration isolation, sound insulation, full floor waterproofing and drainage measures are required for equipment rooms.
Emergency evacuation: as highly enclosed buildings, cleanrooms require at least 2 emergency exits per floor clean area. Personnel purification entrances and air shower rooms shall not be used as evacuation exits.
9.Characteristics of Cleanroom Architectural Design
Architectural design is a core component of clean workshop design. It comprehensively considers production process requirements, equipment characteristics, purification and air conditioning systems, indoor airflow pattern and pipeline layout for architectural plane and section design. On the premise of meeting process flow, it optimizes the spatial layout of clean and non-clean rooms as well as rooms of different cleanliness levels for optimal overall performance.
Core Design Characteristics
Interdisciplinary Technology: Cleanroom technology integrates multiple disciplines. Design requires understanding production process characteristics, workshop construction specifications and pollutant generation & accumulation mechanisms involving physics, chemistry and biology. It also covers air purification, gas & chemical purification, high-purity medium transportation, micro-vibration control, noise reduction, anti-static and electromagnetic interference shielding technologies to solve complex engineering problems.
High Comprehensiveness: Different from ordinary industrial buildings, cleanroom design focuses on creating qualified clean production environments and coordinating multidisciplinary layout conflicts to achieve optimal spatial and planar efficiency at reasonable cost. It emphasizes coordination between architectural design, process design and air purification design, including process flow adaptation, personnel & material routing, airflow organization, building airtightness and decoration applicability.
Space Rational Utilization: Clean workshops integrate clean rooms, production auxiliary rooms, personnel & material purification rooms and utility rooms. Architectural design shall optimize planar and spatial arrangement to maximize space utilization.
High Standard & Cost: Production equipment and construction cost of cleanrooms are high. Complex decoration requires excellent airtightness with strict standards for building materials and structural details.
Composition of Clean Workshops
A clean workshop comprises four functional zones:
Clean Production Area: The core zone whose cleanliness level is determined by production process requirements. Design shall satisfy temperature, humidity, airflow pattern, raw material property, utility demand and environmental control requirements including noise, vibration and static electricity.
Clean Auxiliary Area: Indispensable supporting rooms whose layout directly affects construction cost, operational performance and cross-contamination prevention.
Administration Area: Offices, duty rooms, management and lounge areas confirmed through negotiation with the owner.
Utility Area: Rooms for air purification systems, electrical facilities, high-purity water & gas systems and cooling & heating equipment. Layout varies greatly per product type; purification and cooling/heating equipment are commonly arranged inside the workshop for convenient management and shortened pipeline routes.Warehouse spaces can be integrated with cleanrooms and auxiliary buildings as a comprehensive layout based on raw material properties, quantity and finished product characteristics.
Architectural Plane & Spatial Layout
➤Layout Requirements
Cleanroom plane layout features concise shape, clear functional zoning, reasonable concealed pipeline space distribution, flexibility for process and equipment upgrading, and fire evacuation safety. Common combination forms include adjacent layout, block layout and enclosed layout, with spatial organization based on different spans, heights and column grids.
➤Layout Principles
Production rooms with cleanliness requirements are often partial process zones in comprehensive workshops, mixed with ordinary production areas, auxiliary rooms and utility spaces. Clean and ordinary production areas shall be centrally zoned to optimize personnel & material routing, avoid cross-contamination, facilitate pipeline arrangement and reduce building area.For mixed workshops with both clean and ordinary production environments, personnel & material routing and fire evacuation routes shall be rationally organized to eliminate adverse impact of ordinary production on clean areas. Fire protection and clean production requirements shall be balanced with targeted measures.Clean areas with different cleanliness grades shall be centrally arranged by category following process flow and cross-contamination prevention principles, facilitating rational organization of purification air conditioning and pipeline systems, fire compartmentation and daily operation management.
Post time: May-07-2026