Are the humidifiers harmful to humans?

When used correctly, a humidifier is not harmful to humans. The risks associated with a humidifier mainly relate to the humidity levels in the air. If the humidity is too high, it can cause discomfort, such as chest tightness and difficulty breathing. Therefore, humidity levels should be maintained within a reasonable range.
Additionally, it is crucial to clean the humidifier regularly. If not cleaned properly, mold and other microorganisms in the humidifier can be dispersed into the air with the mist, leading to respiratory issues and infections like pneumonia.
In winter, a comfortable humidity level for the human body is around 50%. Excessively high humidity can cause discomfort, so moderation in using the humidifier is advisable.