In an individual's SpO2 range from 100 to 73 %, this study calibrates and evaluates the accuracy of SpO2 measurement by CW2 in comparison to reference pulse oximeter (Nellcor PM10) or CO-oximetry, Pulse rate (PR) and respiratory rate (RR) were calibrated based on the same Nellcor equipment and the frequency of end-tidal CO2 respectively.

The study is designed in accordance with Medical electrical equipment - Part 2-61: Particular requirements for basic safety and essential performance of pulse oximeter equipment ISO 80601-2-61:2017, Corrected version 2018-02 and ISO 80601-2-55.

SpO2: Testing to confirm the accuracy of the SpO2 monitoring according to ISO 80601-2-61 Clause 201.12.1.101 201.12.1.101

RR Testing: Testing to confirm the accuracy of the respiration rate monitoring according to ISO 80601-2-55. Volunteers respirated spontaneously, no efforts were made to include all ranges of respiration during the study.

PR Testing: Testing to confirm the accuracy of the PR monitoring according to ISO 80601-2-61 Clause 201.12.1.104. No efforts were made to influence PRs of volunteers.

An accelerometer and PPG filters are built in CW2 in order to form the basis to exclude non-eligible test results.

Inclusion Criteria:

1. Healthy non-disabled subjects with American Society of Anesthesiologists health score (ASA) of 1 or 2.
2. The subject is aged ≥18 and ≤ 65 years.
3. The subject is not intellectual disabled, and has provided informed consent and is willing to comply with the study procedures.

Exclusion Criteria:

1. Heavy smokers or individuals exposed to high levels of carbon monoxide that result in elevated carboxyhemoglobin levels.
2. Individuals subject to conditions that result in elevated levels of methemoglobin
3. Individuals with hypoxia (SpO2 < 95 % at 21 % of oxygen)
4. Severe claustrophobia
5. Subject is known with altitude disease
6. The subject is obese (BMI ≥ 31 kg/m2).
7. The subject has a known history of moderate to severe heart disease, lung disease, kidney or liver disease.
8. The subject is diagnosed with moderate to severe asthma.
9. The subject is known with a hemoglobinopathy or history of anemia, e.g. sickle cell anemia, thalassemia, ... who, in the opinion of the investigator, would make them unsuitable for study participation.
10. The subject has any other serious systemic illness.
11. Any injury, deformity, or abnormality at the sensor sites that in the opinion of the investigators would interfere with the sensors working correctly.
12. The subject has a history of fainting or vasovagal response.
13. The subject has a history of sensitivity or allergy to local anesthetics or disinfectants.
14. The subject has a diagnosis of Raynaud's disease.
15. The subject has unacceptable collateral circulation based on exam by the investigator.
16. The subject is pregnant, lactating or trying to get pregnant.
17. The subject is unable or unwilling to provide informed consent or is unable or unwilling to comply with study procedures.
18. The subject has any other condition, which in the opinion of the investigators would make the subject unsuitable for the study.
19. The subject refuses to remove nail-vanish.