Here is the new naming system for thermopile pyronometers, as of 2018.
| Old classification ISO9060 | New classification ISO9060:2018 |
| Secondary Standard | Class A |
| First Class | Class B |
| Second Class | Class C |
In addition, there are newly developed thermopile pyranometers that have a fast response speed (under 0.5 seconds). They are classified as “Fast Response” and can be of class A, B, C.
The International Organization for Standardization (ISO) is an international standard-setting body composed of representatives from various national standards organizations. Founded on 23 February 1947, the organization promotes worldwide proprietary, industrial, and commercial standards.
