Abstract: A humidification system humidifies breathable gas that is supplied to a patient with a ventilator or an anesthesia circuit having inhalation tubing connecting from the ventilator to the patient and exhalation tubing extending from the patient. The humidification system includes a blotting paper humidifier disposed in the inhalation tubing adjacent to the patient. Piping carries an amount of water from a reservoir to the humidifier, and the amount of water delivered to the humidifier is limited by a controllable pulsing valve disposed in the piping. A measurement device measures at least two parameters, and a regulation device regulates the pulsing valve as a function of the measured parameters so that an appropriate amount of water is delivered to the blotting paper to achieve a desired humidity level in the gas.