Most people get oxygen tanks refilled through their home medical equipment (HME) supplier, the same company that originally provided the equipment. But depending on whether you need medical-grade or industrial oxygen, you have several other options including welding supply shops, specialty gas companies, and dive shops.
Home Medical Equipment Suppliers
If you use oxygen for a medical condition, your primary refill source is the durable medical equipment (DME) company that supplies your oxygen system. Large national providers like Lincare operate centers across the country and offer high-pressure cylinders, portable oxygen systems, and concentrators. Most of these companies will deliver refilled tanks directly to your home on a regular schedule, so you rarely need to drive anywhere yourself.
To get medical-grade oxygen, you need a prescription from a licensed physician. Medical oxygen is classified as a prescription drug, and suppliers are prohibited from dispensing it without one. The prescription typically specifies your flow rate and how many hours per day you need supplemental oxygen. Once that’s on file with your supplier, refills and exchanges are straightforward.
Many DME companies operate on a tank exchange model rather than refilling your exact cylinder. You return the empty tank and receive a full one. This is faster and lets the supplier inspect and test cylinders on their own schedule.
Welding and Industrial Gas Suppliers
Welding supply shops and industrial gas companies like Airgas and Praxair refill oxygen cylinders regularly. These businesses primarily serve contractors, fabricators, and hobbyists who need oxygen for cutting and welding, but many also stock medical-grade (USP) oxygen if you have a valid prescription.
If you need oxygen for non-medical purposes, such as metalworking, glass blowing, or other industrial applications, a welding supply shop is typically the most accessible and affordable option. No prescription is needed for industrial-grade oxygen. Most shops can either refill your tank on-site or swap it for a full one. Expect to pay roughly $20 to $50 for a standard tank, depending on size and location.
One important safety rule from OSHA: only the cylinder owner or an authorized person can refill a cylinder, and no one other than the gas supplier should attempt to mix gases. This means you can’t just hand any random tank to any random shop. The supplier needs to verify the cylinder is in good condition and compatible with their filling equipment.
Medical vs. Industrial Oxygen
People sometimes wonder whether there’s a real difference between medical and industrial oxygen. Both come from the same source (air), and USP medical-grade oxygen must be at least 99% pure. Industrial oxygen often meets or exceeds that same purity level, but the key difference is in quality control and chain of custody. Medical oxygen is produced, stored, and handled under stricter protocols to ensure nothing contaminates it between the production facility and your lungs.
For emergency situations, any breathing-grade oxygen at or above 99% purity is considered acceptable. The Divers Alert Network notes this directly: breathing-grade oxygen from a filling station is suitable for emergencies regardless of whether it carries a medical-grade label. But for ongoing home therapy, your supplier should be providing USP-grade oxygen as your prescription requires.
Dive Shops and Specialty Fills
Scuba dive shops fill high-pressure oxygen cylinders as part of their regular business, particularly for technical divers who use enriched air (nitrox) mixes. If you need a small emergency oxygen cylinder filled for diving first aid, many dive shops can accommodate you without a prescription, provided you meet certain conditions.
The FDA allows an exemption from the prescription requirement when oxygen is intended for emergency use. To qualify, you need to show proof of training in emergency oxygen administration (such as a DAN Emergency Oxygen course, valid for two years), and your equipment must deliver at least 6 liters per minute for a minimum of 15 minutes. The cylinder also needs to be labeled “for emergency use by properly trained persons only.”
Refills While Traveling
If you travel with supplemental oxygen, planning ahead is essential. Many large DME suppliers operate offices across the country and even internationally, which means your home provider can often coordinate delivery to your destination. Call your supplier well before your trip to arrange oxygen at your hotel, a family member’s home, or even at layover airports.
For cruise travel, your oxygen supplier can have tanks shipped to the cruise ship before departure and arrange supplies at ports of call. Your provider’s office can help estimate how many tanks you’ll need based on your flow rate and the length of your trip. The general rule is to always arrange more oxygen than you think you’ll use, since travel delays are common.
If you use a portable oxygen concentrator instead of tanks, refills become a non-issue since concentrators pull oxygen from ambient air. Many airlines allow FAA-approved portable concentrators on board, making them the simplest option for air travel.
Cylinder Testing Requirements
Before any supplier refills your tank, they’ll check whether it’s due for hydrostatic testing. The Department of Transportation requires oxygen cylinders to be pressure-tested every 10 years (some newer cylinders qualify for a 15-year interval under a special permit). This test verifies the tank can safely hold high-pressure gas without risk of rupture. If your cylinder is past due, the supplier will refuse to fill it until it passes inspection.
You’ll see the test date stamped into the metal near the top of the cylinder. If your tank is approaching its deadline, factor in a few days for testing before you’ll get it back filled. Many suppliers handle testing in-house, while others send cylinders to a third-party facility.
Insurance Coverage for Medical Oxygen
Medicare Part B covers home oxygen therapy when a patient’s blood oxygen levels fall below specific thresholds. The qualifying criteria require a clinical test ordered by your doctor showing low oxygen saturation, generally at or below 88% at rest, during sleep, or during exercise. Some patients with slightly higher levels (89%) can also qualify if they have conditions like congestive heart failure or pulmonary hypertension.
When Medicare covers your oxygen, the DME supplier bills Medicare directly, and you’re typically responsible for 20% of the approved amount after meeting your deductible. Most private insurance plans follow similar coverage rules, though the specific oxygen saturation thresholds and documentation requirements vary. If you’re paying out of pocket, expect monthly costs for tank rental and refills to range from $200 to $500 or more depending on your usage and location.