Because You Care!

‹ Back

What is the Number of Samples Locations Calculations Readings for ISO14644 ?

 

 

 

The number of sample locations required to verify compliance with ISO 14644-1 (Air Cleanliness Classification by Particle Concentration) is determined by the size of the cleanroom or controlled area. ISO 14644 specifies a formula and provides tables to calculate the number of sampling locations based on the room’s area.

 

 

Calculation for the Number of Sample Locations

 

The number of sample locations is calculated using the formula:

𝑁𝐿=27× (𝐴 𝑚² ÷ 1000)

 

Where:

NL = Number of sample locations (rounded up to the next whole number)

A = Area of the cleanroom or zone in square meters (m²)

 

 

Simplified Table of Sample Locations

Below is a quick reference for typical cleanroom sizes:

  

Room Area (m²)	Minimum Sample Locations
2	2
4	2
10	3
20	5
50	8
100	10
500	23
1000	32
Larger than 1000 𝑚²	Use the above formula

 

 

Sampling Procedure

 

A- Particle Measurement:

• Measure particle concentration at each sampling location for the required particle sizes (e.g., 0.1 µm, 0.5 µm).
• Use particle counters that comply with ISO 21501-4 standards.

 

B- Duration of Sampling:

The volume of air sampled at each location must be sufficient to detect the required number of particles based on the cleanroom classification.

 

C- Uniform Distribution:

Sampling points should be evenly distributed across the room, avoiding clustered locations unless local contamination sources are expected.