HDDs store data on spinning magnetic disks called platters. These platters are sealed inside an enclosure along with the necessary electronics. Traditionally, this enclosure has always been filled with regular air that we breathe. However, as the demand for more storage sky-rocketed over the last couple of decades, HDD manufacturers started using helium instead of air to allow them to produce high-capacity HDDs that wouldn’t be possible with air.

Helium is one of the lightest elements known to humans. It’s much lighter and significantly less dense than regular air. So, when used in HDDs, it creates less friction and turbulence for the platters. As a result, the platters don’t need to be as rigid as in an HDD filled with air. This allows manufacturers to fit thinner and a higher number of platters in the same enclosure, resulting in higher data storage capacity.

Helium HDDs are a relatively new entrant to the data storage space, and it’s been just over a decade since the first commercially available helium HDDs were launched. Besides enabling the production of high-capacity hard drives, the use of helium results in a couple of performance benefits, particularly for the data center and server space where hundreds and thousands of HDDs are used.

As the platters used in the helium HDDs can be thinner, they require less power to spin. Helium also creates less drag than air, which results in even lower power consumption, making helium HDDs more power efficient than HDDs with air.

While helium hard drives have many advantages, it’s essential to be aware of potential drawbacks. One such risk is the possibility of drive failure in case of helium leakage.

Helium has the smallest atomic radius among the known elements, which makes it quite difficult to contain. Hard drive manufacturers spent decades trying to seal HDDs with helium without success. However, modern technologies and years of research have made it possible to hermetically seal the helium drives with a negligible chance of leakage.

However, a fault in the manufacturing processes or wear and tear over the long term can potentially cause the gas to leak and cause the drive failure. That said, according to an old study by Backblaze, a cloud storage provider, helium-filled HDDs had a lower Annualized Failure Rate (AFR) than air-filled HDDs. However, beyond this Backblaze study, the data on their long-term reliability is limited. So this is something to keep in mind.

Besides the leakage, data recovery from a failed helium hard drive is a challenging endeavor. While it’s not impossible to recover data from the helium HDD, advanced tools and technologies are required, which will be incredibly expensive, making the recovery worth the cost only in rare cases.