### Main Signs **Increased Humidity** Constant condensation on windows or a feeling of dampness in the room may indicate poor ventilation. The optimal humidity level in a home is 40–60%. It is especially important to ventilate the kitchen and bathroom. **Stale Odors** If odors from food, pets, or mustiness linger for a long time, it is a signal of insufficient air circulation. **Uneven Temperature** Temperature differences in different rooms may be related not only to insulation but also to poor air distribution. **Worsening Allergies** Frequent sneezing or feeling unwell at home may be related to the accumulation of dust and allergens due to poor ventilation. **Feeling of Stuffiness** If there is a constant lack of fresh air in the room, even with the air conditioner or heating on, it is worth checking the ventilation system. **Technical Issues** Insufficient removal of hot air can shorten the lifespan of household appliances, such as ovens or dryers. ### How to Improve Air Exchange * regularly service ventilation and air conditioning systems * use exhaust fans in the kitchen and bathroom * timely clean and replace filters * ventilate the room by opening windows when possible * turn on fans at low speed for constant air circulation Even simple measures help improve air quality, reduce humidity, and make the home more comfortable and safe for living.