How do we screen for elevated body temperature? Thermal imaging is an excellent non-contact screening tool to detect people with elevated body temperature – if used correctly. When screening for body temperature on the face, the most reliable focal point for temperature measurement is the eye canthus (or tear duct). This is the only area on the face that provides reliable results correlating to the body’s core temperature if the subject is in normal ambient conditions.

Does the Viper EBT system have FDA 510(K) clearance? The Viper system is intended for adjunctive use with FDA cleared thermal imaging cameras [510(K) K033967]. The Viper EBT detection system is a non-contacting imaging system designed to sense elevated body temperatures by measuring passive infrared emissions from the tear ducts or open mouths of humans. The Viper EBT system modifies use of FDA cleared thermal cameras [510(k) K033967] by configuring additional components and proprietary ViperVision EBT Max software to automate body temperature screening that can be remotely monitored. This product is not intended to diagnose or monitor any medical condition or illness and should not be used as such.

How does Viper have the knowledge to supply EBT Systems to address the COVID-19 Pandemic? Thermal imaging technology has been used for EBT for over 15 years – since the SARS, Avian Bird Flu and the Swine Flu epidemics. The Viper team has decades of experience applying thermal imaging technology – for EBT measurement, as well as a host of other applications for various industries.

What is the accuracy of a thermal imaging camera on its own? The standard specification for most thermal imaging cameras, is +/- 2°C or (+/- 3.6°F) or +/- 2% when calibrated and looking at a black body calibration furnace. This does not mean when you take a camera out of the box, power it up and point it at an object, that you are within that camera specification.

Several factors go into making thermal temperature reading reliable and accurate, such as:

• Emissivity the measure of an object’s ability to emit infrared energy. Emitted energy indicates the temperature of the object. Emissivity can have a value from 0 (shiny mirror) to 1.0 (blackbody).

• Spatial Resolution (Spot Size) based on the number detector pixels and the field of view (FOV) of the lens being used. This combination defines the area the imager sees at any given moment. Spatial resolution can be used to help define the smallest object size that can be detected

• Detector/Camera Noise

• Camera Drift

What if I do not have time to wait for people to normalize prior to scanning? There are two common methods that people will use.

a. Rolling Average: As you collect readings, a rolling average will be established. You can then alarm on an amount above average.

b. Measure inside the mouth: A person’s core temperature can be measured by looking inside the mouth. Since this is a different measurement than the Tear Duct method, the settings including emissivity will be different. With ViperVision Max software, you can use different recipes. For instance, if we get the external or outdoor weather conditions, we can automatically switch over to this method.

How is the Viper System more accurate than other systems on the market, or by just using thermal imaging cameras on your own? First, we understand the application and how to make the measurement correctly.

• We know that by following [FDA-recommended] best practices, the only area externally on the face is the tear duct.

• We understand the requirement for cameras that have a small spot size, and utilize the correct optics and distance measurement.

• Infrared cameras can drift when their internal temperature changes. This can happen as they warm up from start up – or if ambient conditions change. If this isn’t compensated for, temperature readings will be incorrect.

• We utilize Calibrated Reference Emitters in the scene’s field of view (FOV). That temperature is fed back into the software and compared to what the camera is actually reading. If there is any error on the camera, the system constantly corrects for that within the software. For instance, when we use a reference emitter, we feed that temperature back in to an I/O device. If the reading from the thermocouple is 90.0°F, and the Thermal Camera is reading 91.2°F, we know the camera is reading 1.2°F high, and the system can adjust the parameters to compensate for this and constantly re-calibrate the camera to read correctly based on a known source.

• By using these methods, the Viper EBT system can achieve better than 0.5°F accuracy.

Is there a way to save these images and access them on our system? Images can be saved, either on an input or alarm. If connected to the customer network, we can use our built in email feature to provide images or reports over email or text alerts.

Can the system be tied in to Access Control? Yes. Since we use different modes of Communications Protocols (Digital IO, OPC, Modbus, Ethernet IP), we can communicate with external devices (both input and output).