By using a humidifier, we can keep the relative humidity in the safe humidity environment(42% to 65%)
Air purifier 空氣清淨機隨著霧霾越來越常見,已有不少人購置空氣清淨機過濾霧霾,只為呼吸到那一口新鮮的氧氣,甚至更有一些民間高人發明了各種低成本的空氣清淨機