What is Class 100/1000/10000 Cleanroom? ISO Standards Explained

Author:Jason Peng
Cleanroom Engineering Technology Manager of Deiiang Company.

Product R&D Manager of GDC Inc. Cleanroom Equipment Manufacturing Company.

Executive Director of Guangdong Cleanroom Industry Association of China.

Engaged in R&D of related products for 15 years, with rich relevant technical experience
2025-05-29 | Visits:

Class 100, Class 1000, and Class 1000 Cleanroomsdefine specific levels of air cleanliness based on the maximum allowable concentration of airborne particles. Governed by the ISO 14644-1 international standard, these classifications are fundamental for industries requiring contamination control.

no more than 100 particles (≥0.5 microns in size) per cubic foot of air. This is the cleanest environment of these three classes. It's critical for highly sensitive processes like Semiconductor lithography, advanced microElectronics manufacturing, and certain sterile pharmaceutical filling operations where even microscopic contaminants cause defects or failures.
no more than 1,000 particles (≥0.5 microns) per cubic foot. A step down from Class 100, it's widely used in pharmaceutical manufacturing (non-sterile), medical device assembly, precision optics, and high-quality electronics assembly. It provides stringent control for processes needing high purity.
Class 10000 Cleanroom: Allows no more than 10,000 particles (≥0.5 microns) per cubic foot. This class offers a controlled environment suitable for less sensitive tasks like device testing, packaging within cleaner environments, some mechanical assembly, and lower-tier electronics work. It's often a cost-effective solution where extreme cleanliness isn't paramount.

Q: Why should I care about these classifications for my facility?

Jason Peng, Deiiang® Lead Designer: Picture your smartphone assembly line - one dust particle can ruin a $1,000 chip. Our Deiiang™ ISO 5 (Class 100) rooms maintain air 100x cleaner than a hospital OR. How? With GCC® certified vertical laminar flow and 300+ air changes/hour.

Q: How does Deiiang® ensure compliance during verification?

Joebo Wang, Deiiang® Senior Validation Specialist: Last month at a vaccine lab, our Deii™ sensors caught 22% higher particles during operational state vs at-rest. We fixed it by recalibrating the:

HEPA filter sealant using Deiiang™ laser scanning
Airflow velocity to 0.45m/s ±5% (iso 14644-1 requirement)
Pressure differentials between zones

Result: Passed FDA audit with zero observations - saving $350K in potential downtime.Project Report #DEII2024-BIO

Classification	ISO Equivalent	Particles/m³ (≥0.5μm)	Typical Applications
Class 100	ISO 5	≤ 3,520	Microchip manufacturing, sterile fill lines
Class 1,000	iso 6	≤ 35,200	IV compounding, medical device assembly
Class 10,000	iso 7	≤ 352,000	Vaccine packaging, pharmaceutical warehousing