The goal of this observational study is to learn about the agreement between sensors analyzing algorithm and body plethysmography in measuring oral and nasal breathing in healthy adults, and in patients with chronic rhinosinusitis, asthma and chronic obstructive pulmonary disease. The main question it aims to answer is: • Is the algorithm-based method accurate enough in analyzing respiratory obstruction as compared to body plethysmography (reference method)? Participants will perform a short breathing protocol (oral and nasal breathing with different masks) during which time their breathing is monitored with both methods.

The data collected in the Patient Registry include: Parameters on general health, like previous illnesses, medications, height, weight, answers to symptoms queries and queries on quality of life (Asthma test, COPD test, Sinonasal Outcome Test 22) as well as results from the examined medical devices (body plethysmography, spirometry, sensors analyzing algorithm).

Inclusion Criteria:

• 5 healthy and asymptomatic volunteers with regard to lungs and nose
• 5 patients with allergic rhinitis or nasal polyps (diagnosis of allergic rhinitis confirmed by a PRICK test or specific Ig E antibody tests and Nasal polyposis diagnosed by an ENT specialist, with endoscopy)
• 5 patients with asthma (diagnosis of asthma based on peak expiratory flow (PEF) monitoring, spirometry, or other appropriate objective measurement methods performed by a pulmonologist
• 5 patients with Chronic Obstructive Pumonary Disease (diagnosis of COPD based on spirometry (post-bronchodilator Forced Expiratory Volume/ Forced Vital Capacity (FEV1/FVC) ratio below 0.70)

Exclusion Criteria:

• Pregnancy.
• History of surgical procedures in the chest, larynx, throat (excluding tonsillectomy), or nasal area.
• Recent illnesses or surgeries that pose a risk to the patient or prevent proper measurement (common contraindications for spirometry):
• Recent (<1 month) myocardial infarction.
• Severe coronary artery disease with easily triggered symptoms.
• Cerebral artery aneurysm.
• Recent brain (<4 weeks) or eye (<1 week) surgery.
• Severe cardiac arrhythmias.
• Pulmonary tuberculosis.
• Pneumothorax
• Immediate postoperative period of lung surgery (<1 day).
• Dementia or confusion.

The healthy volunteers are selected from the personnel or students of Oulu University Hospital and University of Oulu. The patients with allergic rhinitis and nasal polyps, asthma and Chronic Obstructive Pulmonary Disease are selected from the Oulu University Hospital.