What materials are used in modular clean rooms?

Introduction: The Critical Role of Materials and HVAC in Modular Cleanrooms

Modular cleanrooms offer flexible, scalable solutions to meet stringent contamination control standards. The effectiveness of such environments depends greatly on the careful selection of structural and functional materials, as well as meticulously designed HVAC systems. From lightweight aluminum frames to high-efficiency air filtration units, every component contributes to achieving ISO 14644 standards and GMP regulations.

Combining advanced materials with reliable systems, as designed by Deiiang™, ensures environmental stability, safety, and operational efficiency.

Frames: Structural Foundations of Modular Cleanrooms

Frames are the backbone of cleanroom construction. Their selection affects durability, maintenance, and contamination control.

Aluminum Frames

Aluminum offers lightweight, corrosion-resistant properties, highly suitable for cleanroom environments where ease of installation and hygiene are prioritized. Designed in accordance with ASTM B209 standards, aluminum frames by Deiiang™ enable quick assembly and long-term stability.

Steel Frames

Steel provides high strength and load-bearing capacity, ideal for heavy equipment support. Powder-coated or galvanized steel complies with ASTM A123, preventing rust and ensuring hygienic surfaces. Deiiang™’s steel frames are engineered to withstand frequent sanitation processes.

Stainless Steel Frames

Known for exceptional corrosion resistance and aseptic properties, stainless steel frames (grades 304 and 316) are used in ultra-clean areas. Compliant with ASTM A240 standards, they are easily sterilized and are optimal for pharmaceutical manufacturing.

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Figure 1: Modular cleanroom frame structure示意图

Wall Panels: Creating a Controlled Environment

Walls in modular cleanrooms must be airtight, durable, and easy to clean.

Hardwall Panels

Hardwall panels provide robust primary barriers and are designed for high sealing standards necessary for isolating critical environments.

1. Sandwich Panels

Consist of insulation cores such as polyurethane or phenolic resin sandwiched between steel or aluminum facings. These panels offer excellent thermal insulation (R-value of approximately 6-7 per inch) and comply with ASTM C518 standards.

2.Acrylic Panels

Transparent, impact-resistant, and easy to sterilize, acrylic panels are used for observation windows or display zones, conforming with NSF/ANSI 51 standards for food contact and safety.

3. Polycarbonate Panels

Offering high impact strength and optical clarity, polycarbonate panels meet UL 94 HB flame retardancy standards, making them suitable for high-traffic areas requiring durability.

Softwall Panels

Softwall panels facilitate flexible configurations, particularly in temporary or semi-permanent cleanroom setups. Made from PVC or similar flexible membrane materials, they meet iso 14644-1 requirements for low particle emission and are easy to maintain.

flooring: Ensuring Cleanliness and Static Control

Flooring in cleanrooms must be seamless, static-free, and chemical resistant.

Epoxy Resin Floor Coatings

Epoxy coatings provide a smooth, durable, and chemically resistant surface, meeting ASTM D4258 requirements, suitable for high foot traffic zones and heavy equipment areas. The typical thickness is 2-3 mm, with static dissipation properties.

PVC Flooring

PVC floors are flexible, impact-resistant, and anti-static, conforming to EN 13845 standards. They are easy to install, making them preferred for temporary high-grade cleanrooms and laboratories.

HVAC System Components: Ensuring Clean air and Environment Stability

Achieving specified ISO cleanliness classes necessitates a well-designed HVAC system featuring several specialized components:

HVAC System Components Overview

Water System HVAC - Manages humidity and temperature control with ultra-pure water
Fluor System HVAC - Uses fluorinated refrigerants for efficient cooling
Air Handling Unit (AHU) - Filters, heats, and cools incoming air with HEPA/ULPA filters
Compressor - Supplies chilled water or refrigerant for cooling, with VSD for energy efficiency
Supply Air Ducts - Ensures uniform distribution of conditioned air
Return Air Ducts - Recycles air back to the filtration system
Exhaust Air Ducts - Removes contaminated or excess air
Flow Regulation Valves - Precisely controls airflow rate
High-Efficiency Air Diffusers - Ensures even air distribution
Return Air Louvers - Controls and directs return airflow

Air Handling Unit Calculation Example

For a 100m² ISO 5 Cleanroom, typical airflow rates range from 600 to 900 m³/h, ensuring 30-40 air changes per hour (ACH).

ACH = Total airflow (m³/h) / Room volume (m³)
Example: ACH = 900 / 300 = 3 ACH

Note: actual ACH targets are higher for sterile environments, typically 600-900 ACH, so appropriate system sizing is vital.

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Figure 2: Modular cleanroom HVAC system layout示意图

Key Materials and Compliance Standards

Material/Component	Key Standards	Key Properties
Aluminum Frames	ASTM B209	Lightweight, corrosion-resistant
Stainless Steel Frames	ASTM A240	High corrosion resistance, aseptic
Sandwich Panels	ASTM C518	Excellent thermal insulation
Epoxy Flooring	ASTM D4258	Chemical resistance, static control
HEPA Filters	EN 1822	≥99.97% efficiency at 0.3 microns

Frequently Asked Questions (FAQs)

Q1: How often should the filtration systems, like HEPA filters, be replaced?

HEPA filters generally require replacement every 12-24 months, depending on the particle load and operational conditions. Regular testing as per ISO 14644-3 can help determine optimal maintenance intervals.

Q2: What factors influence the selection of duct materials?

Key factors include airtightness, cleanability, corrosion resistance, and compliance with standards such as ASTM E283. Aluminum or galvanized steel are common choices.

Q3: How do I verify that my HVAC system maintains the correct airflow and pressure differentials?

Use calibrated anemometers, manometers, and airflow sensors in accordance with ISO 14644-4 and local regulations during commissioning and routine maintenance to ensure parameters stay within specified ranges.

Conclusion

Building and maintaining a modular cleanroom requires meticulous attention to detail in selecting materials and designing HVAC systems. High-quality wall panels, flooring, and structural frames—such as those supplied by Deiiang™—form the foundation of a sterile environment.

Equally vital are the HVAC components—including AHUs, compressors, ductwork, and airflow regulation devices—that work in concert to deliver precise air purity, temperature, and humidity controls. By adhering to international standards like ISO 14644 and GMP, and leveraging innovative solutions from Deiiang™, facilities can achieve optimal Cleanroom performance, safety, and compliance.