Table 1.
Checklist to ensure correct use of NCIT for tracking human core temperature
Purchasing any NCIT device | Tick if yes | |
---|---|---|
1 | The device has a stated accuracy of ± 0.3°C or lower | ◽ |
2 | The device has a minimum resolvable temperature difference (sensitivity) of 0.1°C. This is often stated as the “resolution” of spot infrared thermometers | ◽ |
Purchasing a thermal imaging camera | ||
3 | The total resolution of the raw image is at-least 320 × 240 image pixels | ◽ |
4 | The device makes drift compensation (self-corrections) to keep the camera within the specified accuracy | ◽ |
If no to above | ||
5 | An external temperature reference source (ETRS, black body calibrator) is used with the device. The ETRS will have a combined stability and drift error of 0.1°C or less over a 14-day period. The ETRS will have an expanded uncertainty below ± 0.3°C | ◽ |
Measurement location | ||
6 | Air temperature is stable, and between 18 and 24°C | ◽ |
7 | Air relative humidity is stable, and between 20 and 75% | ◽ |
8 | The room is free of forced air movement and sources of radiation (i.e., no reflective backgrounds, sunlight) that can impact the NCIT display temperature. A non-reflective cloth backdrop can be used to minimize sources of radiation. | ◽ |
9 | The room is at-least 2 × 3 meters in size | ◽ |
Device operation | ||
10 | The user has consulted the manual to determine the correct measuring location and distance from the subject. | ◽ |
11 | The device is not overdue a calibration (see manufacturer guidelines) | ◽ |
12 | The device emissivity is set to 0.98 for long wave IR cameras or devices | ◽ |
13 | The device has warmed up to room temperature for at least 30 minutes | ◽ |
14 | The device is taking a measurement from a 90° angle and perpendicular to the front of the subjects’ face | ◽ |
15 | For spot measurements, the target is specified as the center of the forehead | ◽ |
16 | For thermal imaging, the target is specified as the inner eye-canthus (i.e., inner corner of the eyelid) | ◽ |
17 | For thermal imaging, the rainbow color scale is used | ◽ |
18 | An absolute temperature threshold has been established through consultation with a healthcare professional or expert in the field of fever screening with NCIT | ◽ |
19 | Masks, eyeglasses, hats, and any other items obstructing the face have been removed | ◽ |
If using an ETRS | ||
20 | The ETRS in focus and large enough to be easily discriminated from the background | ◽ |
21 | The ETRS is no larger than 10% of the size of subject’s face (in a face only image) | ◽ |
22 | The ETRS is set to a temperature close to the threshold temperature (i.e., 35–38°C) | ◽ |
Reporting | ||
23 | Model/manufacturer of camera; accuracy, resolution, model of ETRS, lens type, software & emissivity used | ◽ |
24 | Location, environment (air temperature & humidity), Reflected temperature | ◽ |
25 | Any pre- ‘treatment of subjects scanned (i.e., acclimation to conditions) | ◽ |