Infrared Thermometer Safety Debated in Postpandemic Era

Have you ever experienced the "beep" of an infrared thermometer scanning your forehead? During the pandemic, this non-contact temperature measurement method has become ubiquitous, but concerns about its safety have also emerged. Do infrared thermometers actually pose risks to eye health? As we continue living with COVID-19, how should we properly understand and use these devices?

The Rise of Infrared Thermometers

With the ongoing pandemic, temperature checks have become standard procedure in public spaces. Since COVID-19 patients may develop fever symptoms within 1-14 days after infection, tools that can quickly and accurately measure body temperature are crucial for early detection of potential cases. Infrared thermometers, with their non-contact operation and rapid measurement capabilities, have largely replaced traditional thermometers. They are now widely used in supermarkets, offices, hospitals, hotels, airports, restaurants, and shopping centers, effectively reducing the risk of virus transmission.

Addressing Safety Concerns

However, concerns about the safety of infrared thermometers have circulated on social media, with claims that they can "damage eyes and retinas." Are these claims valid?

In reality, common "gun-style" infrared thermometers—also called laser or non-contact thermometers—do not emit lasers. Instead, they work by detecting infrared radiation emitted by objects to measure temperature. These devices provide fast, accurate temperature readings without emitting any beams that could potentially harm the retina.

The U.S. Food and Drug Administration (FDA) has explicitly stated on its official website that infrared thermometers "can be used to reduce cross-contamination risks and minimize the risk of spreading disease," with no mention of any vision-related hazards. When used correctly, infrared thermometers are completely safe.

That said, certain industrial-grade thermometers equipped with Class III lasers can indeed pose eye hazards. However, these devices are specifically designed for industrial applications and should never be used for human temperature measurement.

Accuracy Considerations

Can infrared thermometers provide accurate readings when used on wrists or arms? Most manufacturers recommend positioning the thermometer perpendicular to the forehead, ensuring the measurement area isn't obscured by hair, scarves, hats, or other coverings. These obstructions can interfere with infrared radiation detection and lead to inaccurate results. For precise temperature readings, the best practice is to hold the thermometer perpendicular to the forehead.

Advantages of Infrared Thermometers

• Reduced COVID-19 transmission risk: Non-contact operation minimizes cross-contamination
• Fast measurement: Instant temperature readings save time
• Portability: Compact and easy to carry
• User-friendly operation: Requires no special training
• Easy maintenance: Simple to clean and disinfect
• Continuous measurement: Can quickly screen multiple individuals
• Wide applicability: Suitable for high-traffic locations like hospitals, airports, schools, and supermarkets

Limitations of Infrared Thermometers

• Environmental sensitivity: Dust and steam can affect accuracy
• Distance requirements: Must be used at proper range for reliable readings
• Learning curve: New users may need time to master proper technique
• Maintenance needs: Sensors require regular cleaning to maintain precision

Proper Usage Guidelines

1. Operators must thoroughly review the specific instructions for their thermometer model, as procedures may vary between brands.
2. Proper presets must be configured before use.
3. Follow all cleaning and disinfection guidelines. Avoid immersing infrared thermometers in water, alcohol, or other liquids.
4. Allow the thermometer to acclimate to room temperature for 10-30 minutes before use.
5. Ensure the measurement area is unobstructed (by tissues, clothing, etc.) and clean/dry.
6. Maintain perpendicular alignment between thermometer and measurement area.
7. Observe manufacturer-recommended measurement distances.
8. Regularly clean and dry the thermometer's sensor.

Important note: Temperature readings should never replace professional medical diagnosis. Individuals with abnormal temperatures should seek medical attention.

When used correctly, non-contact infrared thermometers pose no eye health risks. These devices measure infrared radiation rather than emitting lasers, making them safe and reliable tools for temperature screening. As we adapt to pandemic conditions, proper understanding and use of infrared thermometers remain essential for maintaining public health safety.