HZ info,On November 12, 2025, Beijing Zhongshi Guojin International Laboratory Proficiency Testing Co., Ltd. officially released the results of its latest proficiency testing (PT) program. Inter-China Testing & Technology Co., Ltd. successfully passed the PT program “NIL (2025) PT-5433-016 – Paints and Varnishes: Determination of Mirror Gloss of Paint Films”, receiving a performance rating of “Satisfactory.”

This achievement marks a significant affirmation of the company’s technical capabilities in the field of coating analysis.

The proficiency testing was conducted in accordance with the national standard GB/T 9754-2007, evaluating mirror gloss (20°, 60°, and 85° geometries) with strict accuracy requirements.

Inter-China Testing submitted a measurement result of 53.7 GU (Gloss Units), which closely matched the assigned value of 53.9 GU.

The corresponding Z-score was ？0.1 (|Z| ≤ 2.0 is considered satisfactory), demonstrating excellent precision and reliability.

The test was executed by technical specialist Luo Jiao, and the submitted data passed dual review by Beijing Zhongshi Guojin — resulting in two official recognitions:

the “Notification of PT Plan Results” (including Z-score evaluation), and

the formal “Proficiency Testing Result Certificate” (Certificate No. NIL (2025) PT-5433-016).

Proficiency testing is an internationally recognized method for evaluating laboratory competence through blind sample comparison, providing an objective benchmark of analytical performance.
Inter-China Testing’s “Satisfactory” result underscores the company’s professional expertise in gloss measurement and reinforces its value as a technical support provider for quality control within the coatings industry.

Going forward, the company will continue to uphold rigorous standards, enhance its analytical capabilities, and safeguard product quality with reliable, science-based testing.