We are independent & ad-supported. We may earn a commission for purchases made through our links.
Advertiser Disclosure
Our website is an independent, advertising-supported platform. We provide our content free of charge to our readers, and to keep it that way, we rely on revenue generated through advertisements and affiliate partnerships. This means that when you click on certain links on our site and make a purchase, we may earn a commission. Learn more.
How We Make Money
We sustain our operations through affiliate commissions and advertising. If you click on an affiliate link and make a purchase, we may receive a commission from the merchant at no additional cost to you. We also display advertisements on our website, which help generate revenue to support our work and keep our content free for readers. Our editorial team operates independently of our advertising and affiliate partnerships to ensure that our content remains unbiased and focused on providing you with the best information and recommendations based on thorough research and honest evaluations. To remain transparent, we’ve provided a list of our current affiliate partners here.

How is Normal Oxygen Saturation Determined?

By Vanessa Harvey
Updated May 17, 2024
Our promise to you
WiseGeek is dedicated to creating trustworthy, high-quality content that always prioritizes transparency, integrity, and inclusivity above all else. Our ensure that our content creation and review process includes rigorous fact-checking, evidence-based, and continual updates to ensure accuracy and reliability.

Our Promise to you

Founded in 2002, our company has been a trusted resource for readers seeking informative and engaging content. Our dedication to quality remains unwavering—and will never change. We follow a strict editorial policy, ensuring that our content is authored by highly qualified professionals and edited by subject matter experts. This guarantees that everything we publish is objective, accurate, and trustworthy.

Over the years, we've refined our approach to cover a wide range of topics, providing readers with reliable and practical advice to enhance their knowledge and skills. That's why millions of readers turn to us each year. Join us in celebrating the joy of learning, guided by standards you can trust.

Editorial Standards

At WiseGeek, we are committed to creating content that you can trust. Our editorial process is designed to ensure that every piece of content we publish is accurate, reliable, and informative.

Our team of experienced writers and editors follows a strict set of guidelines to ensure the highest quality content. We conduct thorough research, fact-check all information, and rely on credible sources to back up our claims. Our content is reviewed by subject-matter experts to ensure accuracy and clarity.

We believe in transparency and maintain editorial independence from our advertisers. Our team does not receive direct compensation from advertisers, allowing us to create unbiased content that prioritizes your interests.

Normal oxygen saturation can be determined by using a device called a pulse oximeter, which was developed to measure a patient's blood oxygen level. The small machine is attached to the end of a finger or earlobe into which it sends different colors of light and then measures the amount of light that is returned. A pulse oximeter might be clipped to a toe when measuring for a pediatric patient. It then determines the blood oxygen saturation level and displays the reading on a small screen. If the reading displayed is between 96 and 100%, the patient is said to be normal.

A reading below 96% oxygen indicates a condition known as hypoxia, or an insufficiency in the supply of oxygenated blood reaching the body's tissues. Readings below 86% indicate significant hypoxia, and readings below 85% indicate severe hypoxia. Some oximeters use different wavelengths of light, which permits them to measure the level of carbon monoxide in the blood in addition to the level of oxygen.

Determination of normal oxygen saturation might be part of evaluating the effectiveness of a medical intervention, but healthcare providers cannot always rely on the readings of a pulse oximeter for an accurate oxygen saturation measure in a patient. Situations in which the device cannot be trusted include patients who are suffering hypoperfusion, more commonly known as shock, and victims of hypothermia, or lowered body temperature by exposure to cold, because not enough blood will be flowing through capillaries for a true reading to be obtained. Carbon monoxide poisoning also will produce readings that are higher than the actual oxygen saturation.

People who smoke have carbon monoxide poisoning, so normal oxygen saturation might not be able to be determined with a pulse oximeter when assessing or treating them. Excess movement and the presence of nail polish on a nail also can prevent accurate readings. The most accurate method of measuring oxygen saturation in a patient, many healthcare providers say, is by assessing the physical signs of hypoxia: cyanosis — a bluish color of the lips, nail beds, and fingertips — and cool, clammy skin. When these signs are seen, oxygen levels are likely low.

WiseGeek is dedicated to providing accurate and trustworthy information. We carefully select reputable sources and employ a rigorous fact-checking process to maintain the highest standards. To learn more about our commitment to accuracy, read our editorial process.
Discussion Comments
WiseGeek, in your inbox

Our latest articles, guides, and more, delivered daily.

WiseGeek, in your inbox

Our latest articles, guides, and more, delivered daily.