Clean Room Testing and Certification- American Cleanroom Systems

Cleanrooms are designed to control airborne particulate and environmental conditions. Certification testing is to show they meet the US FED STD 209E or ISO 14644-1 cleanroom standards

Class	Maximum Particles/ft³					ISO equivalent
Class	>0.1 um	>0.2 um	>0.3 um	>0.5 um	>5 um	ISO equivalent
1	35	7	3	1		ISO3
10	350	75	30	10		ISO4
100				100		ISO5
1000				1000	7	ISO6
10,000				10,000	70	ISO7
100,000				100,000	700	ISO8

ISO 14644-1 Cleanroom Standards

Class	Maximum Particles/m³						FED STD 209E equivalent
Class	>0.1 um	>0.2 um	>0.3 um	>0.5 um	>1 um	>5 um	FED STD 209E equivalent
ISO 1	10	2
ISO 2	100	24	10	4
ISO 3	1,000	237	102	35	8		Class 1
ISO 4	10,000	2,370	1,020	352	83		Class 10
ISO 5	100,000	23,700	10,200	3,520	832	293	Class 100
ISO 6	1,000,000	237,000	102,000	35,200	8,320	2,930	Class 1,000
ISO 7				352,000	83,200	29,300	Class 10,000
ISO 8				3,520,000	832,000	293,000	Class 100,000
ISO 9				35,200,000	8,320,000	2,930,000	Room Air

Criteria	Class 10 ISO4	Class 100 ISO5	Class 1000 ISO6	Class 10,000 ISO7	Class 100,000 ISO8
Air changes per HR/Min	500-600 / 8 to 10	300 to 480 / 5 to 8	180 / 3	60 /1	20 /0.33
Filter coverage %	90 – 100	60 – 70	20 – 30	7 – 15	4 – 5
CFM per square foot	85 – 90	36 – 65	18 – 32	9 – 16	4 – 8
Filter Efficiency	99.9997% ULPAs	99.997% HEPAs	99.997% HEPAs	99.997% HEPAs	99.97% HEPAs
Ceiling Type	Aluminum T-bar grid	Aluminum T-bar grid	Aluminum T-bar grid	Conventional T-bar grid	Conventional T-bar grid
Light Fixture type	Tear drop or Flow thru	Tear drop or 2’x4’ cleanroom fixture	2’x4’ cleanroom fixture	2’x4’ cleanroom fixture	2’x4’ standard fixture
Ceiling Panel	FRP, Vinyl rock or Mylar	FRP, Vinyl rock or Mylar	Vinyl rock or Mylar	Vinyl rock or Mylar	Vinyl rock or Mylar
Wall System	Modular or standard built	Modular or standard built	Modular or standard built	Modular or drywall	Modular or drywall
Flooring cover	Welded sheet vinyl or Epoxy	Welded sheet vinyl or Epoxy	Welded Sheet vinyl or Epoxy	Sheet vinyl or VCT	Sheet vinyl or VCT
Flooring base	2” to 6” cove	Cove or Aluminum base channel	Cove or Aluminum base channel	Cove or Aluminum base channel	Cove or Aluminum base channel
Air Returns	Raised floor or center returns	Low wall on long axis	Low wall at perimeter	Low wall	Low wall or ceiling

Cleanrooms can be positive or negative pressure environments that use HEPA filtered air to eliminate particulates.

Typical testing is annual certification. Some pharmaceutical operations are required to do it every 6 months.

As built room particulate counts (per cubic foot). Performed with NIST traceable certified particle counter such as METONE or HACH.
HEPA airflow velocity performed with Short Ridge manometer with VELGRID.
Temperature / relative humidity testing measurements- examines whether the air HVAC controls are functioning properly and uniformly
Room differential air pressure using Short Ridge manometer compares vs. installed magnehelic gauges

Optional tests include:

HEPA integrity
Lighting,
Vibration
Sound tests
Viable particulate sample plate
Continuous particle testing

Testing is often required as part of maintaining USP797 or USP800 standards for compounding pharmacies. USP800 for hazardous materials require negative pressure rooms. USP797

For medical device or pharmaceutical companies it may be required as part of their GMP (good manufacturing practice) and FDA validation processes.

For food companies it may be part of their NSF (former National Sanitation Foundation) testing plan.

For industrial companies it is often part of their ISO9001 quality plan.

FAQs About Cleanroom Testing and Certification

Q: What Is The Difference Between Viable vs. Non-Viable Cleanroom Testing?

A: Viable testing is for live microorganisms such as yeast, mold, or bacteria. Viable testing is typically done in pharmaceutical or medical device cleanrooms where sterility is key concern. Settling plates come with TSA or SDA media to promote growth. Humans are primary source of viable contamination. Non-viable cleanroom testing is done with a laser particle counter. The laser cannot differentiate between live or inert particles.

Q: How Do You Measure Cleanroom Air Flow Patterns?

A: Cleanroom air flow pattern test uses smoke sticks to map air flow in a cleanroom. It is used to determine dead spots or non-laminar flow areas.

Q: What Is Individual HEPA Testing?

A: Some HEPA filters are designed with test ports where a technician can inject special tracer gases. No gases should pass thru the HEPA filter back into the room. Other tests include surface scanning of the HEPA for leaks and putting a manometer hood or Velgrid velocimeter on the HEPA to measure air flow in cubic feet per minute.

Q: What Is A Cleanroom Recovery Test?

A: This test is to determine how much time it takes for a cleanroom to return to its cleanroom classification after contaminants are introduced. It is typically only done before the cleanroom is put into production. The contaminants are special aerosols that are designed not to damage the cleanroom.

Q: How Do You Test Cleanroom Flow Benches?

A: The most common test is an at rest particle test. Other tests that can be done include smoke stick for air pattern flow, HEPA leak testing, air velocity testing and settling plate (viable).

Q: How Do You Determine How Many Test Samples To Take In A Cleanroom?

A: Per ISO14664-3, the number of test samples is dictated by the area (ft²or M²) of the cleanroom.

Q: Why Do People Test For Temperature and Humidity In Cleanrooms?

A: The cleanroom users manufacturing process can have tight temperature and humidity specification which are needed to comply with the FDA validation (ex. pharmaceutical or medical device) or acceptable manufacturing yield (ex. semiconductor photolithography).

Q: What Is Cleanroom Light Testing?

A: The purpose of cleanroom light testing is to ensure that cleanroom workers have sufficient light to do their job properly. Testing is typically done with a light meter to measure footcandles at working height.

Q: What Is Cleanroom Sound Testing?

A: The purpose of cleanroom sound testing is to protect employees from extreme sound levels that can damage their health or prevent effect communication inside the cleanroom.

Q: What Is The IEST?

A: The IEST (Institute of Environmental Science and Technology) is a nonprofit technical society that makes recommendations and implements cleanroom ISO standards.

Cleanroom Testing and Certification