• the lens may be soiled: the presence of dust or dirt filters the passage of the infrared emissions; as s consequence, Thermofocus will take a lower reading than the real body temperature.
    It is necessary to clean the waveguide gently, using a cotton swab that has been slightly dampened with alcohol. Don’t use the thermometer for at least 30 minutes after cleaning.
  • The forehead can show signs of sweat or an oxygen mask is present or the subject is elderly. This can result in a low reading In all the above cases, you can take the temperature reading, again from a distance, on th eyelid (answer 10). – Oils or make-up con be present. This can results in a low reading. You can take the temperature reading, again from a distance, on the eyelid or on the neck (answer 10).