Beauty is skin deep, so goes a saying.
So, if the skin becomes too dry, cracked and itchy as the air humidity plunges below 50%, moisture to keep the skin soft and soothing is not a luxury but to many a necessity.
Humidifiers are designed precisely for this purpose - to deliver moisture into the air when the weather is too dry to sooth the unpleasantly dry feeling on your nose, lips and body.
In a comparative test on 10 models of humidifiers, the Consumer Council evaluated them for safety and water output capacity - with reference to the latest international IEC safety standard and the American AHAM standard.
The test found no serious deficiencies though definitely room for improvement.
For instance, in the safety test were revealed: dimension of the drain hole a bit small (5 samples); insufficient insulation between or on the internal wires (8); inadequate material resistance to flame and heat (5). In general, all 10 humidifier models are considered safe to use under normal operation.
The ozone concentration of the 4 samples with negative ion generators was found to be in compliance with the standard.
The water output capacity was measured with mixed results. For energy efficiency, in the extreme case, the heater type could run up as much as 8 times the energy for the ultrasonic type to produce the same output.
Nevertheless, humidifiers are not high energy consumers; even the sample with the lowest humidifying capacity is capable of delivering moisture for a 25 sq. meter room, according to the AHAM formula.
On their claims on area of use, 5 samples were found to claim an area smaller than the actual calculated area. But on their output capacity claims, the reverse was true: the actual measured values in 4 samples were lower, by 20% to 57%, than their claims.
To use humidifiers safely, users are recommended to pay extra attention to the need of regular cleaning and maintenance of the water tank and the ultrasonic vibrator. Sterile water or cooled freshly boiled water should be used to fill the water tank as far as possible. If the water used is not clean enough, minerals and micro-organisms in the water could be sprayed together with the moisture into the air.
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