Breathing air applications are not just restricted to checking the quality of compressed gas in breathing sets and systems fitted for patients in hospitals but also the breathable levels of oxygen in compartments that might hold inerting gas generation equipment or electrolysers. These are often unmanned, and a remote monitoring system is required to allow safe entry.
Some ships and refinery plants have fire suppression systems using gases like Inergen, Argonite and FM 200. These remove oxygen from the atmosphere. If they are used, then the compartment or enclosed space in which they are used needs to be checked that Oxygen levels are safe for entry.
What measurements are essential for breathing air?
About 78% of the air we breathe is nitrogen, an average of 20.9% (at sea level) is oxygen. The balance consists of argon and then trace amounts of CO, CO2, water vapour and noble gases such as neon and helium.
Instruments to monitor breathing air and breathable atmospheres form a core of products available from Process Sensing Technologies (PST). PST instruments and sensors can be used to check moisture content, and oxygen content as well as N2, CO and CO2 levels.
Humidity and moisture measurements
A certain level of humidity is necessary for breathing air. If the air is too dry, it will dry out the user’s breathing passages which will be uncomfortable at the very least and may also be dangerous over long periods or in certain situations. On the other hand, too much moisture in the breathing apparatus may damage valves or encourage bacterial growth.
Portable hygrometers are ideal for making spot-checks of breathing sets, bottles and fixed gas lines. It’s important to select one that is capable of measuring moisture in gas at line pressure.
Online hygrometers are suitable for providing continuous measurements of compressors at the point of delivery.
Oxygen, CO and CO2 measurements
Hand-held O2and CO monitors are a convent way to check oxygen levels in tanks of breathing air, as well as check for dangerous levels of carbon monoxide (CO). Monitoring for CO is especially important since CO poisoning is very often fatal.
Ambient O2 monitors ensure safety in confined spaces where there is a risk of gas leaks. They sound alarms if O2 levels drop below safe levels.
Measuring O2 levels in gas generation systems confirms the purity of oxygen produced. These analyzers may also include CO, CO2 and moisture sensors to provide a full picture of the breathing gas quality.
Diving gas mixtures
Technical and commercial divers breathe a special gas mixture of nitrogen, helium and oxygen. The ratios of these gases vary depending on the depth of the dive and a specialist Trimix or Heliox Analyzer is recommended.
What is a breathable atmosphere?
A breathable atmosphere is one where oxygen is kept between 19.5 to 23.5%: this is the OSHA (Occupational Safety and Health Administration )1910.146 regulation.
If O2 levels drop below 19.5 and down to 16% the cells in the body do not get the oxygen needed for their correct function. Below 14% down to 10% physical activity becomes exhausting and below 6% fatalities will happen. Loss of consciousness can occur quickly: within 40 seconds.
Altitude also affects oxygen levels. As altitude increases, atmospheric pressure drops and the air thins out. Because of this, the composition of the air also changes, with a gradual reduction of the normal gases (Oxygen, Nitrogen and Argon) and an increase in Hydrogen and Helium.
For example, you can expect oxygen levels of 20.9% at sea level but at 2000m it is just over 16% O2, and by the time you reach 7,500 m you are down to 8%. This means that with each breath you receive less oxygen which can lead to hypoxia, also called ‘altitude sickness’ - which can be fatal.
Breathing air sets: Self-Contained Breathing Apparatus, SCBA
These are used by the emergency services and generally consist of one or two bottles filled with a clean compressed air to a pressure of 200-300 bar connected to a sealed mask, or a mouthpiece with a demand valve that drops the pressure of the compressed air to a breathable level.
Breathing air standards do vary but not by much, for example:
Europe BS EN12021:2014 | US CGA G-7.1.2011 Grade D | Australia & New Zealand AS-NZS 1715:2009 | |
Oxygen | 21 +/- 1% | 19.5-23.5% | 19.5-22% |
Carbon Dioxide | ≤ 500 ppm | ≤ 1000 ppm | ≤ 800 ppm |
Carbon monoxide | ≤ 5 ppm | ≤ 10 ppm | ≤ 10 ppm |
Oil | ≤ 0.5 mg/m3 | ≤ 0.5 mg/m3 | ≤ 1 mg/m3 |
Water airline <40 bar | Storage 5°C below lowest storage temperature: where storage and usage temperatures is not known pressure dewpoint will not exceed -11°C | Dewpoint≤ 50°F (67 ppmV, for SCBA use in extreme cold dew point not to exceed -65°F (24 ppmV) or 10°F lower than the coldest temperature is worn in. | |
Water high pressure | 40 to 200 bar ≤ 35 mg/m3 | ≥100 mg/m3 for cylinders initial filled to pressure of at least 120 B |
What instruments are recommended for breathing set testing?
Michell MDM300 high-speed portable hygrometer. This is also available with a tough Peli case, and is capable of measuring moisture at line pressure.
SF82 Online Hygrometer for charging compressors for delivery.
Analytical Industries AII-3000 and Palm O2 handheld monitors measure oxygen levels in tanks of breathing air. The Palm CO ensures that CO levels are not dangerous.
Instruments to ensure safety of divers’ breathing air
Diving should be considered a separate breathing air application. Divers’ air should also conform to BS EN12021.
Further, it is divided into two categories, depending on the diving depth the swimmer must get to or work at.
Sport divers and shallow water divers can work on standard 21% O2 with a balance of N2 to a depth of 30m.
Technical and commercial divers reach depths below 30m. At these depths, high N2 levels can cause nitrogen narcosis. This has the effect of causing a drunken-like effect and can be fatal.
Also, by reducing the amount of nitrogen in a diving set and substituting it with helium the effects of and decompression times to reduce the bends can be reduced. The bends, decompression sickness or Caisson disease, can occur both in divers and for people at high altitude. Nitrogen can come out of solution as bubbles in the blood and can affect the whole body including joints, heart, lungs and brain. The term ‘bends’ came from the cramped-up body shape divers suffering from it took to try and relieve the pain.
Advanced sport divers and professional divers (such as those in various Navies tasked with bomb and mine recovery and disposal as well as commercial divers working on oil & gas platforms) will use either a trimix gas or heliox in their diving sets.
Below 65m even oxygen can become toxic to the central nervous system as the partial pressure of oxygen rises at depth. So extra helium is used to reduce the amount of oxygen, a typical trimix could be 15% O2, 55% he, and 30% N2.
PST equipment for diving air set testing:
Michell MDM300 high-speed portable hygrometer.This is also available with a tough Peli case, and is capable of measuring moisture at line pressure.
SF82 Online Hygrometer for continuous measurements of moisture at the compressor.
Analytical Industries AII-3000 and Palm O2 handheld monitors
Analytical Industries AII Trimix 4001 automatically calculates and measures the correct mix of helium, oxygen and nitrogen for technical divers.
Decompression & Hyperbaric chambers
The decompression chamber is used by deep commercial divers in order to compress and decompress them in a safe manner. It is surface-supplied and is essentially a living space with an airlock for transfer of food etc. It can also be connected to a diving bell. Divers can spend several days in one as they are compressed and decompressed.
The hyperbaric chamber is used in medical treatment and it can also be used to treat altitude sickness by placing a victim in an oxygen-rich atmosphere to aid their recovery. This can be for post injury operations and circulatory diseases where an increased level of oxygen at pressure is beneficial.
PST equipment for decompression and hyperbaric chambers:
Michell MDM300 high-speed portable hygrometer. This is also available with a tough Peli case, and is capable of measuring moisture at line pressure.
SF82 Online Hygrometer for continuous measurements of moisture at the compressor.
Analytical Industries AII Trimix 4001 automatically calculates and measures the correct mix of helium, oxygen and nitrogen for technical divers.
Hospital gases
Hospitals use a wide variety of gases, the main ones are:
These gases can either be distributed by a network of pipelines or, in cases like the CO2, be delivered direct from a bottle. Many hospitals have gas production and storage areas.
Medical Air & Gas - Compressed Air Testing - Trace Analytics (airchecklab.com)
The gases used for breathing again must conform to BS EN 12021
PST equipment for hospital gases:
Michell MDM300 high-speed portable hygrometer. This is also available with a tough Peli case, and is capable of measuring moisture at line pressure.
SF82 Online Hygrometer for continuous measurements of moisture at the compressor.
Analytical Industries AII Trimix 4001 automatically calculates and measures the correct mix of helium, oxygen and nitrogen for technical divers.
Ntron MoGas Medical Gas Analyzeris designed to confirm the purity of oxygen generated for medical use.
Confined spaces and rooms
The HSE definition is: A confined space is a place which is substantially enclosed (though not always entirely), and where serious injury can occur from hazardous substances or conditions within the space or nearby (e.g. lack of oxygen).
These could be N2 generation areas for inerting gases, or electrolyser facilities where both H2 & O2 are being produced.
There can also be hypoxic areas. These are areas with low oxygen levels either for fire prevention (libraries storage for example) or to prevent oxidation of food stuffs, or paints and chemicals.
Monitoring equipment such as the Ntron Gasenz and Ntron OxyTx for hazardous areas can give warning of low O2 levels. These would be permanently mounted in the spaces. Their displays can be placed in normal habitable areas or their outputs sent to warning systems in control rooms.
CO and CO2 are both gases which need to be monitored in confined areas, or rooms with low ventilation areas.
Carbon Dioxide levels in confined spaces
As a guideline the following levels apply to CO2 which occurs at 0.03% in normally breathable air:
250-350 ppm: Normal, outside air-breathing level. Low risk
350 - 1,000 ppm Normal, indoor air-breathing level. Low risk
1,000 - 2000 ppm: Elevated levels in poor quality air, higher risk of drowsiness
2,000-5,000 ppm: High Levels in poor quality air: dizziness, nausea, increased heart rate will occur
>5,000 ppm UK Long Term Exposure Limit (8 Hour Reference Period)
>15,000 ppm: UK Short Term Exposure Limit
Carbon Monoxide levels in confined spaces
The following applies to CO which is a lethal gas (source Wikipedia):
Effects of carbon monoxide in relation to the concentration in parts per million in the air:
Concentration | Symptoms |
35 ppm (0.0035%) | Headache and dizziness within six to eight hours of constant exposure |
100 ppm (0.01%) | Slight headache in two to three hours |
200 ppm (0.02%) | Slight headache within two to three hours; loss of judgment |
400 ppm (0.04%) | Frontal headache within one to two hours |
800 ppm (0.08%) | Dizziness, nausea, and convulsions within 45 min; insensible within 2 hours |
1,600 ppm (0.16%) | Headache, increased heart rate, dizziness, and nausea within 20 min; death in less than 2 hours |
3,200 ppm (0.32%) | Headache, dizziness and nausea in five to ten minutes. Death within 30 minutes. |
6,400 ppm (0.64%) | Headache and dizziness in one to two minutes. Convulsions, respiratory arrest, and death in less than 20 minutes. |
12,800 ppm (1.28%) | Unconsciousness after 2–3 breaths. Death in less than three minutes. |
We offer the following options for monitoring carbon dioxide and carbon monoxide levels in confined spaces:
The Rotronic Monitoring System is a complete cloud-based monitoring system that can be used to monitor CO2 levels in confined spaces or areas with limited ventilation.
Rotronic offers a dedicated CO2 display, which also displays temperature and humidity, for complete indoor air quality monitoring.
Ntron Microx 406, Carbon Dioxide Analyzer and the Ntron Microx 401, Carbon Monoxide Analyzer are cost-effective units that provide reliable and fast responses to changes in air composition. Contact us to find out more about these options.
Have a question? Get in touch!
Our team of application specialists will be happy to discuss your specific breathing gas application. Use this form to contact us.
FAQs
What are the OSHA standards for breathing air? ›
Human beings must breathe oxygen . . . to survive, and begin to suffer adverse health effects when the oxygen level of their breathing air drops below [19.5 percent oxygen]. Below 19.5 percent oxygen . . . , air is considered oxygen-deficient.
What are the safety rules for compressed air? ›Wear the appropriate personal protective equipment (PPE) for the task. Safety glasses are always required when using compressed air or pneumatic tools, and face guards or shields and hearing protection are required with some impact tools. Gloves and steel-toed shoes may also be required.
What is the lowest oxygen level to live? ›Humans need oxygen to live, but not as much as you might think. The minimum oxygen concentration in the air required for human breathing is 19.5 percent. The human body takes the oxygen breathed in from the lungs and transports it to the other parts of the body via the body's red blood cells.
What is the required grade of breathing air to be used in an SCBA? ›To ensure SCBA air quality, NFPA 1500 suggests a minimum CGA Grade D air quality. CGA Grade E breathing air quality is an improvement on CGA Grade D, allowing for use in both SCBA and SCUBA applications.
What are the OSHA allowable percentages for oxygen in breathing air? ›19.5 % Minimum acceptable oxygen level.
What are the OSHA requirements for oxygen monitoring? ›OSHA specifies that a hazardous atmosphere may include one where the oxygen concentration is below 19.5% or above 23.5%. The device alarm and warning levels should be set according to these oxygen concentration levels.
Does OSHA regulate air standards? ›Currently, OSHA has no indoor air quality (IAQ) standards but it does provide guidelines about the most common IAQ workplace complaints.
What are three 3 hazards of using compressed air to clean yourself? ›Compressed air accidentally blown into the mouth can rupture the lungs, stomach, or intestines. The high decibel sound of compressed air blown in or near the ears can cause permanent hearing loss. Compressed air can enter the navel, even through a layer of clothing, and inflate and rupture the intestines.
What is the OSHA safety for compressed gases? ›OSHA standards require the compressed gas cylinders to be in an upright position (vertical) or valve end up position. This requirement is provided to ensure the protection of and safe access to the valve while in use, during movement, or while in storage.
What is the highest survivable oxygen level? ›It refers to altitudes above a certain point where the amount of oxygen is insufficient to sustain human life for an extended time span. This point is generally tagged as 8,000 m (26,000 ft, less than 356 millibars of atmospheric pressure).
What is a dangerously low oxygen level while on oxygen? ›
If blood oxygen saturation levels fall to 88% or lower, seek immediate medical attention, says Dr. Lutchmansingh.
What happens when your oxygen level drops to 80? ›If the oxygen saturation drops below 85%, the severe lack of oxygen affects the brain. The person may experience vision changes and lose consciousness. Severe Hypoxemia: When the blood oxygen levels drop below 80%, the brain, liver, and other vital body organs get affected.
What is the minimum acceptable amount of oxygen allowed for a supplied air system? ›§ 84.79 Breathing gas; minimum requirements.
(a) Breathing gas used to supply apparatus shall be respirable and contain no less than 19.5 (dry atmosphere) volume percent of oxygen.
The SCBA is only compliant with standards set forth for CBRN masks. The first stage regulator keeps the pressure to the mask-mounted regulator at approximately 80 psi throughout the entire operating pressure range of the cylinder.
What is the allowable concentration of CO in breathing air? ›Exposure Limits
[OSHA PEL] The current Occupational Safety and Health Administration (OSHA) permissible exposure limit (PEL) for carbon monoxide is 50 parts per million (ppm) parts of air (55 milligrams per cubic meter (mg/m(3))) as an 8-hour time-weighted average (TWA) concentration [29 CFR Table Z-1].
A normal level of oxygen is usually 95% or higher. Some people with chronic lung disease or sleep apnea can have normal levels around 90%. The “SpO2” reading on a pulse oximeter shows the percentage of oxygen in someone's blood. If your home SpO2 reading is lower than 95%, call your health care provider.
What is oxygen safe limits? ›OSHA dictates that the minimum "safe level" of oxygen in a confined space is 19.5%, while the maximum "safe level" of oxygen in a confined space is 23.5%.
What is normal oxygen level in air? ›Normal atmospheric air at sea level has a pressure of 760 millimeters of mercury (mm Hg). Because air contains approximately 21 percent oxygen, oxygen's contribution to the total pressure, in other words its partial pressure, is 21 percent of 760 mm Hg, or about 159 mm Hg.
What are three guidelines for working safely around oxygen? ›Never place the tank or machine near an open flame (e.g., matches, lit candles, a stove in use). Keep the oxygen tank at least six feet away. Always turn your oxygen off when not in use. Always check the oxygen levels on your oxygen tank.
What are the OSHA standards for the minimum and maximum levels of atmospheric oxygen in a confined space? ›General Procedures
An atmospheric test should be performed in the confined space to ensure the required ambient conditions—less than 10 percent LFL, greater than 19.5 percent and less than 23.5 percent oxygen, and less than the PEL of a contaminant—exist.
What is the minimum type of respirator required by OSHA? ›
Approved respirators: full facepiece pressure demand self-contained breathing apparatus (SCBA) certified by NIOSH for a minimum service life of thirty minutes, or. combination full facepiece pressure demand supplied-air respirator (SAR) with auxiliary self-contained air supply.
What does OSHA say about air quality? ›OSHA does not have a general IAQ standard, but does provide guidelines addressing the most common workplace complaints about IAQ, which are typically related to temperature, humidity, lack of outside air ventilation, or smoking.
Does OSHA require air testing? ›There is no Federal OSHA requirement specifically addressing the use of compressed air to test for leaks in gas lines. There are several applicable general industry and construction standards addressing the hazards of compressed gases. In the construction standard, Subpart J, Welding and cutting, §1926.350.
How do you measure air quality at work? ›- Purchase an indoor air quality monitor. High-quality monitors will test for particulate matter, chemical pollutants, humidity, carbon monoxide and even formaldehyde.
- Install carbon monoxide alarms. ...
- Conduct a radon test. ...
- Buy a mold test kit.
- Gas up after dusk. Refueling any motorized vehicle or appliance allows the escape of vapors that, on summer days, can lead to ozone formation. ...
- Don't overfill your tank. ...
- Drive smart. ...
- Keep your vehicle in excellent running condition. ...
- Clean diesel is not an oxymoron. ...
- Gas saving tips.
Safety goggles, gloves, and hearing protection are appropriate for any compressed-air cleaning task. Safety goggles prevent any stray particles from flying back into the user's eyes.
When using compressed air what is one thing you should never do? ›Never Point Compressed Air Towards Your Body
I'm sure this is common sense to most people, but it's still worth noting that you should NEVER point the nozzle of compressed air towards your body or anyone else.
Non-liquified gases are also known as compressed, pressurized, or permanent gases. Oxygen, nitrogen, helium, and argon are all examples of non-liquefied gases. Dissolved gases are very unstable chemically.
What are the two main hazards posed by compressed gasses? ›Compressed-gas hazards include oxygen displacement, explosion, and toxic effects as well as the physical hazards of a ruptured cylinder. Employers must evaluate compressed-gas hazards and have an emergency-response plan that defines procedures and responsibilities to address emergencies.
What does OSHA consider high pressure? ›No employee shall be subjected to pressure exceeding 50 pounds per square inch except in emergency.
What is the lowest oxygen level in air before death? ›
Fainting and unconsciousness begin to occur at 8 percent to 10 percent oxygen. Death occurs in 8 minutes at 6 percent to 8 percent oxygen; recovery is possible after 4 to 5 minutes if oxygen is restored.
What is a good oxygen level for a 70 year old man? ›What Is the Normal Oxygen Level for the Elderly? The normal oxygen saturation level is from 97 to 100%. Older adults usually have lower levels of oxygen levels as compared to younger adults. If a person is older than 70, a normal oxygen level could be around 95% instead.
What happens if your oxygen level is 75? ›Doctors consider oxygen levels to be low when they are below 60 millimeters of mercury (mm Hg). Shortness of breath, dizziness, and other symptoms may occur. Blood oxygen level usually range from 75–100 mm Hg. If they fall below 60 mm Hg , there may not be enough oxygen reaching the body's vital organs.
How can I raise my oxygen level quickly? ›- Stand or sit up straight. Rather than lying down, which may put pressure on your lungs and make it harder to breathe.
- Cough. If you have a cold or the flu, difficulty breathing can decrease oxygen saturation in your blood. ...
- Go outside. ...
- Drink lots of water. ...
- Take slow, deep breaths.
Most people will die within 10 minutes of total oxygen deprivation. Those in poor health often die much sooner. Some people may suffer other medical catastrophes, such as a heart attack, in response to oxygen deprivation.
Which finger is best for pulse oximeter reading? ›Then rest it on your chest for five minutes. Switch the pulse oximeter on. Then attach the clip of the pulse oximeter to the finger next to your thumb, or your middle finger. Watch the numbers on the pulse oximeter.
What are the signs that a person needs oxygen? ›If you have a health condition that causes low levels of oxygen in your blood (hypoxia), you may feel breathless and tired, particularly after walking or coughing. Fluid may also build up around your ankles (oedema) and you may have blue lips (cyanosis).
What is the most common cause of low blood oxygen? ›Low amounts of oxygen in the blood (hypoxemia) can lead to hypoxemic hypoxia, the most common cause of hypoxia. Hypoxemia can be caused by lung and heart diseases, congenital heart defects, and medications that slow your breathing.
Does oxygen level drop during sleep? ›When we sleep, the oxygen level in our blood drops, due to interruptions in breathing. Lung and sleep disorders tend to decrease those levels further, and dangerously so. But the range of those levels during sleep varies widely between individuals and, researchers suspect, is greatly influenced by genetics.
What are the 5 rules that must be followed when oxygen is in use? ›- Never smoke, and don't let others light up near you. ...
- Stay 5 feet away from heat sources. ...
- Don't use flammable products like cleaning fluid, paint thinner, and aerosol sprays.
- Keep oxygen containers upright. ...
- Skip products with oil, grease, or petroleum.
What are the 3 types of oxygen? ›
- Compressed gas systems.
- Portable oxygen concentrators (POCs)
- Liquid oxygen systems.
The phenomenon of pulmonary toxicity is commonly referred to as the Smith effect. This can occur after prolonged exposure to oxygen >0.5 ATA. The incidence of displaying pulmonary symptoms with oxygen toxicity is 5%.
How many breaths is 500 psi in SCBA? ›So 500 PSI = 75 breaths.
What is the minimum volume of air in SCBA? ›The volume of air contained in the SCBA cylinders should be at least 1,200 litres, which shall be capable of providing air for at least 30 minutes.
What is the minimum pressure before use in BA set cylinder? ›The working pressure of the cylinder shall not be less than 300 bar and the test pressure shall be 1.5 times the working pressure. 4. The cylinder shall be approved by CCOE and certificate to that effect shall be submitted along with the tender.
What percentage of CO2 in air is safe? ›CO2 gas at room temperature will not injure the skin or eyes. What OSHA standards and exposure guidelines apply? OSHA has established a Permissible Exposure Limit (PEL) for CO2 of 5,000 parts per million (ppm) (0.5% CO2 in air) averaged over an 8-hour work day (time-weighted average orTWA.)
What is the safe level of exposure for CO and CO2? ›The WHO recommended limits are: 9-10 ppm for no more than 8 hours. 25-35 ppm for no more than 1 hour. 90-100 ppm for no more than 15 minutes.
What are three 3 items which need to be checked prior to using a compressed air or gas powered nail gun? ›Ensure that the compressed air supplied to the tool is clean and dry. Dust, moisture, and corrosive fumes can damage a tool. An in-line regulator filter and lubricator increases tool life. Keep tools clean and lubricated, and maintain them according to the manufacturers' instructions.
What is the NFPA standard for compressed air? ›Compressed Breathing Air Systems
Compressors must be operated for at least 30 minutes each week with two condensate drain cycles. Air stored in steel cylinders must be replaced at least annually. The air system intake location must be acceptable and marked with a placard.
Compressed air can break through skin and cause minor injuries, but if the air enters into the bloodstream, and travels to the brain or heart, stroke or heart attack symptoms can occur. Blowing air from a compressed air system into your mouth can cause ruptures in the lungs or stomach.
What are the 4 components of a compressed air system? ›
- compressor.
- air cooler.
- air receiver tank.
- filter.
- dryer.
- condensate trap.
- distribution system.
- NEVER POINT IT AT YOURSELF OR ANOTHER PERSON! ...
- NEVER USE IT TO CLEAN CLOTHING OR HAIR! ...
- ALWAYS FOLLOW PRESSURE RATINGS AND LIMITATIONS! ...
- ALWAYS CHECK THE CONDITION OF HOSES AND LINES BEFORE USE! ...
- ALWAYS WEAR PROPER PPE!
The Code defines three specific types of compressed air systems in the food industry; systems with contact with food, non-contact high-risk, and non-contact low-risk.
What is the OSHA requirements for compressed air? ›The enclosed Occupational Safety and Health Administration (OSHA) standard 29 CFR 1910.242(b) requires that compressed air used for cleaning purposes must be reduced to less than 30 psig (pounds per square inch gauge, 204 kPa).
What is the air compression limit? ›Atmospheric air has 14 PSI of pressure (1 bar) but can be forced up to 6004 PSI (414 bar) of pressure when compressed into a smaller state. Exactly how pressurized compressed air becomes is determined by science.
What are the NFPA 99 instrument air requirements? ›Medical Air Dewpoint Summary
Level 1 and Level 2 Medical Air Systems are required, by the NFPA 99 Standard, to provide a 32 F pressure dewpoint at supply pressure. Medical air is produced and dried at 100 psig pressure and then regulated down to 55 psig for distribution in the pipelines.
Compressed air gets used across a range of industries to provide respiratory protection. It's used in applications where the risk of breathing ambient air is too high to mitigate using half or full-face respirators. But it is not safe to breathe the compressed air directly following compression.