During the lead-up to the solar eclipse a number of unsafe solar shades were being imported into the USA; most were incorrectly labeled ISO compliant, while some were fake, and in some cases included counterfeit versions of legitimate vendors. Once the story broke in national press there was a desire from local schools systems to find unsafe shades and ensure that students did not use them. Testing was undertaken to find simple methods to identify unsafe shades, and to find a way to quantify the possibility of being unsafe using more accessible probes then expensive spectrophotometers. Using a Vernier LabQuest2, a pynometer probe, cellphone camera, and extensive personal experience; several unsafe viewing shades were found. These shades transmitted light levels of over 2-3x the light levels of known, safe shades under various broad spectrum light sources. Typical irradiance using the pynometer was in the range of 1100 w/m^2. Known safe shades reduced levels to 5-6 w/m^2. Unsafe shades had levels from 8-13 w/m^2 or more. Additional shared traits of unsafe shades were noted, including common graphics, solar shade shapes, and in some cases the manufacturer being counterfeit. Information was posted on social media and shared with amateur astronomy groups and vendors to aid in finding any unsafe glasses. The equipment limits did not allow researchers to determine if a given set of shades was safe, only if a given set of shades was definitively unsafe. Using these data a minimum of 400 unsafe solar eclipse shades were removed from local school stocks before the eclipse and several thousand unused shades were tested and discarded after the eclipse to prevent misuse or injury.

This document is currently not available here.