Calibration FAQs

What is Linearity Verification Testing (LVT)?
Linearity Verification Testing (LVT) confirms that a photometer responds accurately and consistently across multiple concentration levels, not just a single point.

• Electronic Linearity: Verifies internal signal response
• Aerosol Linearity: Confirms photometric accuracy using test aerosol concentrations

Together, these tests offer comprehensive calibration confidence.

Why is this important for my application?
Precision matters when you’re monitoring cleanrooms, pharmaceuticals, or any health-critical environment. These enhanced calibrations reduce measurement uncertainty and risk. These enhancements do not change the functionality of your photometer. They improve the accuracy, consistency, and auditability of your calibration certificate, which supports better compliance and reduces regulatory risk.

Is ATI the only company that offers this?
Yes. ATI is currently the only photometer manufacturer offering a calibration service that includes ISO/IEC 17025 accreditation / ISO 9001 certification, and combined aerosol and electronic linearity verification.

This unique combination positions ATI as the industry leader in validated calibration precision.

What is ISO/IEC 17025 calibration, and why does it matter?
ISO/IEC 17025 calibration is the international gold standard for calibration laboratories. It confirms that ATI's calibration methods are scientifically valid, consistently applied, and meet rigorous quality standards. It took ATI three years to achieve this significant accreditation.

What has changed in ATI’s photometer calibration services?
All 2i Photometers now include ISO/IEC 17025 accredited calibrations, including Linearity Verification Testing (LVT), which ensures your photometer performs accurately across its full range—both electronic and aerosol systems.

Was the data from the older ARS Carts invalid or wrong?
Not at all. Our historical calibrations met industry standards. What’s changed is the rigor and validation behind our process. We've raised the bar with new research and upgraded equipment — not corrected a flaw.

What research did ATI conduct? What motivated ATI to do this? Where can I learn more?
ATI wrote three technical papers posted on the ATI website on the importance of particle size distribution. Please review them for more data and information. Each paper reviews the importance of consistent particle size distribution and proper gravimetric measurements.

Will this impact the “As Found” or “As Left” values?
"As Found" values remain unchanged. We are still using the ARS cart for this part of the process.
"As Left" values may appear different due to improved particle size control with the CALIBRA™ Precision Aerosol Source — which is a good thing and reflects enhanced consistency in our measurement setup. If you require a technical comparison or deeper explanation, we can connect you with a subject matter expert.

Why is particle size distribution important in 2i calibrations?
Particle size directly affects how the test aerosol interacts with the photometer. Inconsistent sizes produce inconsistent readings. Our updated calibration cart, CALIBRA™ System, ensures more consistent particle size distribution compared to older systems — delivering tighter tolerances and better repeatability.

Can other calibration systems achieve the same accuracy?
Based on current industry knowledge, competitor systems do not maintain particle size distribution as precisely as the CALIBRA™ Precision Aerosol Source.

Will this impact existing calibration procedures?
The procedures remain familiar, but results will be more consistent and within tighter tolerances.

Will this increase turnaround time or cost?
With the addition of ISO/IEC 17025 accreditation, advanced verification protocols, and ATI's significant investment in calibration science, service pricing has modestly increased.

The added cost supports:

• Maintenance of our accredited lab and processes
• Additional steps in verification and documentation
• Use of advanced calibration equipment like the CALIBRA™ System

Keep in mind, this nominal increase delivers substantial value — you now receive the highest industry standard of calibration, helping reduce costly rework, improve compliance, and increase confidence in your data.