British Lung Foundation
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How serious can oxygen saturation below 90 be?

Here is a comment I made on the Team Inspire website, and one reply I got which does cause me some concern. I would like to know what others think.

Comment:- I bought myself a pulse/oximeter online to monitor my oxygen saturation during exercise. I have been diagnosed with IPF after a VATS biopsy. I do get breathless, especially when going up too many stairs. My normal resting sats are about 95, but when I exercise they drop to about 83, but this does not stop me, I just keep going. Pacing yourself so as not to become too breathless is my advice, and if you do become breathless, then take a rest.

I realize that lots of people with IPF are much worse off than myself, I do not need oxygen, and hopefully will never need it.

I am 56 yrs old, and I am concerned how this lung disease is going to affect me as I know it is progressive.

I personally think your body tells you when you need to slow down, and that is all the advice I can give at the moment.

Best wishes to you all with this awful lung condition,

Tony :-)

Reply:-And side note to Tony....pacing yourself will not stop organ damage. You're right, don't stop exercising...but use supplemental oxygen while you're exercising so your saturation level never falls below 90. If your oxygen is falling to 83 you most definitely are doing internal damage. This is a progressive disease, but the side-damage you're doing could kill you before the pulmonary fibrosis does...or can make your quality of life drastically worse. You cannot stop the progression in the lungs, but you can keep the rest of your body working properly longer if you use supplemental oxygen when needed. Please talk to your doctor about dropping to the low 80s. Feeling short of breath is not a good indication of how bad your saturation level is. (for example, I do not feel short of breath until my saturation level is in the 70s...and that is shortly before I get dizzy and pass out.) Your body will not tell you about the internal damage until it is too late...the heart attack or stroke will just happen one day. The warning you're getting now is the number that shows on your pulse oximeter. Below 90: Danger! You are doing internal damage! More oxygen is needed, stat!

Is this information true? I would be very grateful to hear what you all think. I am not going to stop the exercise as it is something I have done for years.

Most of the members on the Team Inspire website are American, and they can be a little dramatic about things sometimes. So I would love to hear what my fellow Brits think. Cheers.

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On my PR assessment my starting rate was 93 falling to 85 on exercise. The PR team would not let me join the group until I had an oxygen tank. Organ damage was the reason given. I took their advice.



I did the COPD rehabilitation course and my first assessment was the same as yourself 93 falling to 84 on exercise. Had to do several laps walking around chairs spaced in a circle for 5mins, at my own pace. There the physio stopped after a while to test stats. After rest I resumed to normal (well it is to me) 93. So now if I am doing anything physical for more than a couple of minutes I use my amulatory oxygen. Otherwise I wouldn't do any exercise at all.

I am not qualified to comment on this and think your best action would be to phone the BLF helpline 03000 300 555 and ask them. They will be the best people to seek clarification on your concerns.

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There is a cause for concerns and if you haven't already spoken to your doctor about this I think you should. Of course its your call, but to continue to exercise with low oxygen levels can lead to organ damage, cardiac and respiratory failure.

Your've probably already read about it, but here it is again:

i received this from a friend

oxygen levels will rob you of your eye sight, short term memory, and your energy. Eventually low oxygen levels will weaken your heart muscle. Read that last sentence again. It is that important.

The world is facing an epidemic of heart failure! This issue is drastically shortening life span and it is just so unnecessary!

Your low oxygen levels may precede a heart failure diagnosis, but if you are experiencing low oxygen levels, you can count on developing heart failure because low blood oxygen saturation levels CAUSE heart failure!

So how low IS too low?

Facts to Remember About Blood Oxygen Saturation Levels

When oxygen saturation levels fall below 92%, the pressure of the oxygen in your blood is too low to penetrate the walls of the red blood cells.

So, oxygen is unable to access transportation to your cells, tissues, and organs.

It is a matter of gas laws.

Every time your oxygen level falls below 92% saturation the cells of your body are oxygen starved!

4. When you fail to meet your oxygen needs, every organ in your body suffers the consequences.

5. Low oxygen levels may be present only at certain times.

when retaining excessive fluid

when airways are reacting to irritants

with respiratory illness

while sleeping (with or without sleep apnea)

about 3:00am when you wake gasping for air

with activity when your heart muscle has become weak (though isn’t technically “congestive heart failure”….. yet)

Recurring low oxygen levels are harmful and should be treated with supplemental oxygen.

If oxygen levels are low, deterioration will occur in every single incidence.

There are no exceptions to this rule.


Low oxygen levels are definitely something to worry about!

If you feel you may be experiencing low oxygen levels be sure to insist that your doctor check your “pulse oximetry reading”.

I've recently been prescribed ambulatory oxygen and find it helps me go that little bit further!



I am a CO2 retainer was was advised by COPD consultant and nurses that my oxygen levels should be between 88-92. I have been on LTOT oxygen therapy 15 hours daily since February '14. Now I am worried.

Hello malinka, I understand that below 88 is cause for concern, not 92 as I was led to believe.My sats are often below 88 but I will discuss it with the nurse next week, try not to worry. I'll let you know what they say,I have an appointment next Weds.huff x


Yes for people with COPD, 88-92% oxygen saturation is an acceptable range with some room for variance. If you have anything lower and there is no apparent reason for this...e.g exertion, anxiety, smoking; then you should see your GP. Especially if you are experiencing any abnormal respiratory distress. Remembering that having COPD is like having asthma constantly. You will never been symptom free.

Good advice! This is what I have been told by my Pulmonary DR.

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That is so scary I never knew all that. I am only 19 and I have bad ashthma and was scared to go to the doctor and I was having asthma attacks ever month for about 2 weeks and I went to the doctor after i could actually walk and was feeling better and my oxygen levels were around 60 percent and under and my doctor sent me to the hospital and told me she didn't know how I was consious and I was probably going to die if I went home....mind u i was FEELING BETTER....thats scary to know what I was doing to my body for 3 year

Thank you all for your replies. I think I will make an appointment to see my GP. The one thing that surprises me is that when I visited my consultant, he did not seem too concerned by my levels of oxygen during exercise. So feel a little confused.

Best wishes to you all :-)

Good the GP will listen to your concerns and address the matter, hope you get some answers, we have to take responsibility for our own health and insist on the best possible course of action! good luck and please let us know how you got on :)

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Some doctors don't know gp didn't

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Hi, I have an oximeter that has alarms for my sats & pulse i have alarm set to sats 90% & pulse at 150. by doing this i never drop below 90%. My FEV1 is 23% my sats at rest are 95%. I do not use oxygen yet but when the time comes i will do so. I am 69 yrs young and intend to continue a while longer. All the above comments are correct low sats do cause organ damage. I would suggest that you take your oximeter with you when you go to see you Dr. and check it against his. I have 2 and take them with me every time i visit my pulmo.


Hi Dave, I am very interested in your oxymeter could you let me know where you got it from and its make as I am in the middle of researching them with the intension of buying one. I am looking for one that will give accurate readings during exercise, and with the alarms you mentioned.

hope you can help, thanks.


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Hi Colin, my oxymeter is model MD 3001 made by; Beijing Choice, Electronic Tech Co LTD. web site,

I bought it from Amazon when we were in the UK last year can't remember how much. I am satisfied with it. I use it while exercising every time. I also do an occasional sleep check. It came with software for saving or printing charts etc. the 90% O2 lets me know to keep my eye on things I will go down to 88% sometimes but when I stop I recover in a minute or two so no problem. By the way my FEV 1 at last test has dropped to 19% but without any noticeable effect. I have checked it, and my back ups, on a couple of occasions at the hospital and no problem. Hope this is of some help anything else I can help with just ask. Cheers Dave from the LoS.

Thanks very much Dave I will be checking it out asap, sounds like a good piece of kit going by your rxperience.

My pulse oximeter is a Anapulse 100. It does the job for me. Take a look at this link

If you have IPF make sure your consultant knows what he is talking about its a rare condition one that a lot of consultants have little or no knowledge of. Try to get your GP to refer you to a specialist IPF centre of excellence there are a number around the country. I sacked my first consultant after three years of incorrect medication and a totally indifferent attitude to exercise, It was the best thing I could have done, I am now with the Newcastle RVI first class people, and treatment, open minded and respectful of the patients experience of their condition.

Please research my advice on the American sites they are very informative and demand the best.

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It's easy to become confused. I read one sight that says 88-92 02 sats ok for people with copd; I read another that said below 92 in anyone is dangerous, another sight said should always be 95-100. Doctor told me it should be 95 and over with oxygen therapy, but the portable oxygen usually puts me at 90-92, and he said that was ok as long as it stays above 89 and I don't stay on the portable long????????????

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You have to remember that COPD is an umbrella term for a number of inflammatory and destructive lung disorders. One of them being emphysema. These people are CO2 retainers and develop a tolerance to living of lower saturations. As there drive to breath is dependent on higher CO2 levels than the rest of us. Ultimately this is a terminal illness.

hufferpuffer is spot on. I used to do what you have been doing. Until I felt like I was dying and had done a little damage to my heart. As hufferpuffer said, you WILL do damage with sats that low whatever anyone tells you. Ask for an oxygen assessment. With sats that low. You WILL be offered supplementary oxygen for mobility. Refuse it at your own risk. I know of three people that have died through refusing oxygen. And dozens that have used it for up to and over a decade.


Hi Tony,

I'm on oxygen 24/7 and go to pulmonary rehab a couple of days per week where they keep a close eye on my oxygen levels which believe it or not have dropped as low as 59 (after exercise) no one made any comment about this so obviously I wasn't concerned but after reading your blog I'm now very concerned. All my docs,nurses etc. seem to keep me in the dark, it's not as if I'm the hysterical type so thanks to you I will delve into this more closely.

(wonder how accurate these pulse oximeters are)



My pulse oximeter seems to vary and change as I sit here. Just read my left hand finger as 70 pulse and 95 sats. My right hand finger read 120 pulse and 92 sats. Can't get to grips with these readings. Seems my right hand doesn't know what the left hand is doing!


Same here my left hand says 96 my right 97 oh well at least they are both well over 90 but only I add with the aid of my home oxygen machine - for which I am very grateful. Without it I was down to low 80's all the time and was rushed into hospital - so guess it is dangerous as others have said and on the damage issue I may now have a heart problem (was probably without knowing it with a low oxygen level for nearly a year or at least with it gradually decreasing during that time, although I knew something was wrong) - please get it checked and good luck.

Thanks for the post, you learn something new every day, who needs doctors when we can come here and find all the info we need. Guess my GP surgery should pop in here now and again lol x

I've been on oxygen for over 4 years, using home concentrator 16 hrs a day at 2lts/min, and supplied with portables. On oxygen at rest my sats are approx 93. Off oxygen at rest approx 87. Advice from doctor has been to increase hours usage of concentrator as needed but to maintain 2 litre flow rate. My problems come on exercise when off oxygen even gentle walk takes them plumetting to below 70. Even on oxygen they still fall to high 70's. Awaiting appointment at Glenfield for walk test and fully expect them to increase my portable flow rate substantially. But at no point have I got any sense of alarm by the medical profession at these low numbers - you've really got me worried now. On the plus side my blood pressure is stable and heart rate steady at 70 (at rest).

I just went to the doctors yesterday, I had been feeling weak and dizzy and my oxygen level was 86 when she checked me, the nurse told me that, that was a normal reading so I didnt think twice about it, but tonight I am having trouble breathing again and a tightness in my throat, when I looked up oxygen levels I found this website....should I be concerned I am 26, Im not overweight and no health problems that I am aware of

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For a normal fit healthy person with no medical conditions, no medications your oxygen sats should be 95-100%. 86 is well below normal.


I am not qualified to give advice either. What I do know aboutd obstructive lung disorders is that it is normal for for people with these disorders to sat lower than normal and 88 -92 % on air is normal. If sats are too high (>95-100%, it can cause repiratory dificulties. potentially even cause then person to stop breathing. This is because carbon dioxide clearance is depending on low oxygen levels. even so, 83% is quite a low reading and could be doing some damage. I will say that a lot of things can affect the readings you will get on a pulse oximeter. Periferal skin temp, sweat, carbo monoxide levels if you are a smoker, nail polish and dirty hands. One way to determine accuracy is to manually check your radial pulse and compare it with the pulse reading on the oximeter. I also highly reccomend talking to your GP or specialist about this.

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I will say, if this is only during exercise (short term) and you get those sat levels back up to 92% after. I wouldn't be concerned.

The human body is highly resilient and can take a drop in oxygen saturation. I would be more concerned about prolonged low oxygen saturation's. Not sudden drops from exercise where your cells will be quickly using up your available oxygen reservoir. Just make sure you get them back up again.

Hi Jaydubb13

Sorry to hear about your problems with your heart and asthma. What I was talking about above was specifically to do with certain COPD patients. COPD being a term for a number of lung disorders, not one specific disorder. Some COPD patients are what we call CO2 retainers. meaning that they have higher levels of CO2 and lower O2 sats than a healthy set of lungs. Your mother may not have been one of these. CO2 levels in our blood is what causes us to breathe autonomically. put simply CO2 levels increase, then we breathe to get rid of the CO2 and inhale O2. With a certain type of COPD patient they require a higher level of CO2 in order to breathe. They develop a sort of tolerance to having lower sats. This is not a belief of mine or something I have just read from Wikipedia, It is something I have been taught and that I deal with for a living. At the time I wrote this (2 years ago) I was not qualified and I made that clear. But now I am qualified and I still agree with what I said above. I would only like to add that it's not all COPD patients who are CO2 retainers. And if they are they will most likely know. Even so, I would not even take the advice of an expert of here as the word of God. Someone said above that everyone's health is their own responsibility. I agree with this. We are on here to share ideas and give opinions, not to diagnose or give specific medical instructions that replace a GP visit. If my above comments don't satisfy your understanding then I implore you to reach out and extend your knowledge, read books, talk to experts. You don't have to take anything I say as absolute. I wouldn't expect you too. But please don't come on here and attack me and say that I am copying and pasting from websites and delivering information directly from a book. Because I'm not. I am a trained medical professional and I deal with a range of medical complaints weekly.

Thank you.

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my last attack my stats went down to 54% I think even the ambulance people were surprised I was even alive - me too ha,ha, xx


wow thought i was the only 54%er, high five ya made it too


Hi mike yes and 2 years later I'm still here - fingers crossed ...... for awhile anyway ....

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After two bad colds/infections over xmas my oxygen sats were 91 at rest and they fell to 85 unloading the weekly shop [which I did at a fast pace to test]. My Nurse [who I saw today] said my sats at rest should not go below 90, EVEN DURING EXCERSISE. I am know being sent to the Oxygen assessment clinic.

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'Researchers ... have demonstrated that, contrary to prevailing dogma, hypoxia can be remarkably beneficial to the heart. These discoveries, to be reported in the June 2008 issue of Experimental Biology and Medicine, may lead to a new paradigm to protect hearts of patients at risk of coronary disease. Hypoxia is generally considered harmful to the heart, since a steady supply of oxygen is required to maintain cardiac function.

However, this research has demonstrated that a 20 day program of brief, repetitive, moderate reductions in the amount of oxygen in the arterial blood induce adaptations which increase the heart's resistance to the more severe insult of a heart attack. . . .'

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Well its two years down the line, and I am still here, and still not requiring ambulatory oxygen. However my exercise regime is not what it was. I hardly go to the gym now, I still work full time, but at my next appointment with my consultant I will be discussing ending my working career as it is getting increasingly difficult. I can tell the lungs are getting worse as the cough is getting worse, and during a coughing fit my sats drop to low 80's. Hopefully I will do the 6 MWT at my appointment, and have the full pulmonary function test, to get a good idea of how my lungs are performing. Been on pirfenidone for 17 months now.

take heed it is dangerous, my levels drop even more drastically than 83! has been 70! that is just walking a few yards. I have been told that unless I use oxygen when I am doing anything at all physical as otherwise the consequenece could be that I will just stop breathing.

Well after my last visit to see my consultant, I had a 6MWT and I am now using ambulatory oxygen. I use it for any exertion as that is when my saturation drops. Two years ago I did not require oxygen, now I do. The oxygen really does help, but needing it now just shows that this dreaded IPF is progressing. I have good days and bad ones, but now the weather is improving I do feel a lot better. Take care everyone :-)

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Here's something for you all to consider..., and I feel many of you probably have already discovered it on your own..., and that is that your doctors, for whatever reason, whether ignorance or simply not 'thinking of it', often don't let you in on what seem to be the simplest of information..., such as what I just discovered from my next door 80 year old neighbor who's not even on oxygen and that is to always use your left index finger for your oximeter reading as it is closest to your heart and gives the higher reading.

In the 3 years of being on oxygen therapy, I didn't know that.

Surprise, Surprise, Sargeant !!!

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Also the same for checking Blood Pressure. If you check both left & right arm & the reading is 10 points or more difference you could possibly have arterial damage. Doctors are supposedf to check both arms but rarely do.

I am a CO2 retainer and on 1/2 litre oxygen min 15 hours daily and was told by the medical professionals that my levels were fine between 88-92.

Now you have got me worried.


I agree with the first reply you received, the response was perfect. I have had heart failure, and respiratory failure at the same time. It hit me suddenly, and this was how I found out that I had a progressive lung condition. My heart healed, but my lungs won't heal I was told by the doctor before being sent home, which gave me a lot to think about, since my health was perfect before this all happened to me. But, to make a long story short, I was in picture perfect good health, and then one day I woke up, and found their was little oxygen in the atmosphere for me to breath...I hated this feeling. Anyhow, six month's later of living like that, and I was rushed to the hospital, and admitted. For six month's I went living daily with very low oxygen, and never once did I think about my heart, and looked what happened. Now, I am wheelchair bounded and on 24/7 oxygen, and in severe stage. They still are trying to figure out what type of lung condition I have, but have found that my lungs are not damaged, but my airways are inflamed quite a bit, and they feel it is either severe asthma or some kind of scarring. Ask your doctor about prescribing you oxygen with activities. I strongly feel that is what you need.

I do have oxygen now seawave, and I use it. It helps me out a lot.

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Americans dramatic? Oh, come on! Please?! Really??! Just kidding. Sites like this can be very helpful, when not being very dangerous. I've been doing a bit of research . . .

My GP of 2009-2011 got fired--by me--for prescribing me an inhaler for my COPD to which I was allergic. I told her about the allergy. I took the inhaler, wondering. I took it for 18 months then quit, after the last 6 months showed me the inhaler was making me cough more rather than less. She--the fired GP--was "unconvinced" about my COPD even when the first set of test--using nebulized albuterol, showed some. My GP of 2012-2016 was also skeptical, based on his (like the prior GP's) stethoscope/listening examination. However, I knew my smoking and inhaled-dust and -pollutants history. My last test showed lung function (expanded "spirometry". for a brief, albeit insufficient explanation) showed results "consistent with mild COPD".

. . . I've also been doing research. This 88-90 percent figure is "bandied about" too quickly, probably too often, and--I'm making a slightly educated guess--TOO out-of-context. I just read a brief explanation of emergency-room supplemental-oxygen treatment for COPD-sufferers that advised using sup'-O2 to get blood oxygen saturation levels to 88-92%. Then--!THEN!--the author commanded blood-gas analysis. This may be due to the fact that if you give the wrong person too much sup'-O2, you can actually make them worse. I don't understand all the various feedback mechanisms (including, but not limited to the bio-sensors in the upper-chest near the carotid arteries and veins). I certainly don't understand biology very well, despite having "aced" a semester of pre-nursing biology. I DEFINITELY DON'T understand blooc chemistry, especially the chemistry of blood-gasses and their interactions, i.e. too much O2 can cause CO2 in the hemoglobin to move into the blood-plasma, evidently that's NOT A GOOD THING to have happen.

So, please, all you Brits--and you Yanks and Johnny Reb-types that are over here with me "across the pond"--don't assume a bit of reading online can make you an authority.

I started monitoring my blood oxygen saturation level after a doctor--in a hospital, who'd reviewed my mother's file, after she'd had surgery and had anesthetic-induced complications including having to be put on sup'-O2 to get out of the ER where she was moved after the ER (well, the peri-operative services room, after the anesthesia-recovery room), because her BOSL had been too low, stayed too low, and she did not progress through the stages of anesthesia recovery properly, thus scaring several OR and POS nurses--told me to monitor her at home. So, I started monitoring myself. AND, I scared the [deleted] out of myself with mid- to low-80s readings. So, I went to my GP.

GPs tend to be skeptical. Especially if they're also the GP (I'm guessing, here) of a fellow family member, or well informed about that individual, who has faked three or four heart-attacks. So, some self-knowledge is a good thing to have, to protect one's self and to argue with doctors when the need arises. However, it's always best to defer to them as best and as long and as well as one can as they've been through medical-school and most of us have not.

After more self-monitoring, more self education, coming out of some denial, I'm now waiting for a sleep-apnea test as that may be a part of my problem.

A lot of my problem appears to be that my BOSL goes to low when I sleep and when I'm inactive. I've taken it with a pulse-ox meter, immediately on awakening, and gotten consistent readings of 83-84. I've taken it when awakening panting (I'd always thought I was just breathing very deeply--which seemed to be a good thing--and very fast. Ahh, [light-bulb came on over my head], that's called 'Denial!" which is not a river in Egypt ("THE Nile"). So, I continue to advocate, strongly for my own health, but, I also continue to defer to my doctor's, my GP's, medical opinion. He finished medical school. I've finished . . . ? . . ., well, writing this.

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i have o2sats usually between 94% and 98% during the day but when im just sitting or laying down watching tv and tired they drop to between 90% and 94%... when i am active walking or working they seem to stay up.. what concerns me is that when im laying down very sleepy and relaxed ill put the pulse ox on my finger and it might reak 90% 10 93 % then i cough or take a deep breathe and it goes back up to betwen 95 - 98 is this normal... i have mild emphysmea with pft numbers bewtween 77 fev1 and 89 fev

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I totally agree with your comments And confirm what you are saying to be factual. Keep excercising, use your 02 when ambulant and keep those sats at 90 at least.

See your UK Dr or Respiratory nurse and they will put you on the right path and organise your needs.

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