Heated humidification in CPAP therapy is often not enough to prevent side effects like dryness of nasal mucosa and xerostomia, especially in cases of mouth breathing or mask leakage. Additionally a higher level of humidification in lower ambient room temperature can lead to condensation and irritating noises. Compliance of affected patients decreases considerably. Regarding this, devices with humidifier and additional heated tubing are developed to automatically regulate optimal humidification and temperature right up to the mask. The efficacy of a system with controlled heated humidification and heated tubing in nasal masks under various conditions like leakage and different pressure levels is object of this study.

Participants will breath 3 hours during daytime with a nasal mask under three different humidity modes (No humidity, controlled heated humidification, controlled heated humidification with heated tubing) with CPAP 8 and 12 mmHg and with and without leakage. The ambient room temperature is controlled with air conditioning. Changes in temperature and humidity is measured inside of the mask with a humidity sensor and recorded. After each phase the participants subjective opinion about humidity and temperature is asked.

Inclusion Criteria:

• Age 20-70
• Obstructive Sleep Apnoea Syndrome

Exclusion Criteria:

• Other severe acute or chronic nasal disease (rhinitis, sinusitis), Cardiovascular disease, respiratory or neurologic disease
• Incapable of giving consent