When storing foodstuffs, especially fruit and vegetables, air temperature and humidity control is needed to preserve the quality and freshness of the produce. If relative humidity is too low, generally lower than 90-95%, some of the moisture may be lost from the food, reducing its selling weight and worsening its appearance, and even causing the food to perish earlier than normal. In a controlled environment, on the other hand, such processes are slowed down enormously by the dual effect of low temperature and high humidity. Take preservation of bunches of grapes as an example. For certain varieties, the recommended temperature is -1°C, with a relative humidity between 90 and 95%. If the air is too dry, the result is that the grapes release some of their moisture. Losses exceeding 3% make the berries lose consistency and shrink. The same phenomenon is even more evident in vegetables, whose weight is 80% to 95% water. Recommended storage values differ considerably for different types of vegetables: at a temperature of 0°C, for example, relative humidity should be 70% for onions, and 95% for spinach. In general, moisture losses of 5% will change the produce's features, to the extent where it can no longer be sold. To overcome these problems, cold rooms can be equipped with humidifiers, so as to guarantee the right relative humidity and ensure optimum food preservation. Carel supplies a vast range of controllers and humidifiers for these applications, with different flow-rates and operating characteristics. These are systems featuring high efficiency and very low energy consumption, which guarantee maximum reliability and safety.