Is Reverse Osmosis Water Purified? Let’s Find Out!

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Reverse osmosis is a popular filtration method advertised to remove many different contaminants in water.

But let’s look beyond the noise. Just how clean is reverse osmosis water? Is reverse osmosis water purified?

Keep reading to find out!

Key Takeaways

  • Reverse osmosis removes up to 99.9% of impurities from water. As such, reverse osmosis water qualifies as purified water in most cases.

What Is Purified Water?

According to the EPA, purified water is water that has been treated to meet the U.S pharmacopeia standards. Purified water is essentially free of chemicals and contains less than 10 ppm of total dissolved solids.

Another definition of purified water is that it has been processed to remove microorganisms.

What Is Reverse Osmosis Water (Purification)?

Reverse osmosis water is water that has been purified using reverse osmosis. It is much purer than regular tap water and is almost only H2O molecules.

Reverse osmosis purification is the process of purifying water with a reverse osmosis membrane. It works by forcing water through a tiny-pored semipermeable membrane under high pressure. Because the pores are so tiny, only water can pass through them, and pretty much all impurities are left behind.

blue reverse osmosis membrane

Is Reverse Osmosis Water Purified?

So, is reverse osmosis water purified water? Yes, it usually is.

  • For one, reverse osmosis is a water purification method. It’s one of the many ways to purify water.
  • Furthermore and as discussed before, RO water is almost pure H2O often containing less than 10 ppm TDS which means it falls in the category of purified water as defined by the EPA.
  • And lastly, reverse osmosis water is usually free from microorganisms which is the other definition of purified water.

That being said, RO water does not always count as purified. If the feed water quality is horrendous and the water contains extreme TDS levels, the RO product water is less likely to come out completely purified. The higher the TDS level in your feed water, the more tasking it is for your RO system to eliminate all of it and a TDS level of higher than 10 ppm is highly likely.

Other factors that may affect the purity of RO water include feed water pressure and temperature, membrane age and condition, and pre-treatment.

Which Is Better, RO or Purified Water?

Generally speaking, reverse osmosis and purified water are both pure and safe for drinking. But because so many factors determine how “pure” reverse osmosis water turns out, purified water might be a bit purer.

But when it comes to judging which is better, we must remember that the healthier drinking water is always the one that contains fewer harmful contaminants. For example, calcium and magnesium are common impurities in water but aren’t harmful. On the other hand, heavy metal contaminants like lead are always harmful.

So if purified water and RO water both contain these contaminants, the better water will be the one with less contamination.

Benefits of RO Water

RO water is superior to unfiltered water and provides many benefits. It is mostly free from contaminants including:

  • Sediments
  • VOCs, pesticides, disinfection byproducts, and other organic chemicals
  • Heavy metals
  • Salts and minerals
  • Radiologicals

As such, the benefits of RO water include:

  • Better taste: RO water does not contain contaminants that cause bad taste or smell. Chances are, your first glass of RO water will be worlds better than the tap water you’re used to, especially if your tap water is heavily contaminated. You’ll never want to go back.
  • Improved drinking habits: Having an endless supply of clean drinking water (that tastes good) can encourage you to drink more of it. Since RO water tastes so good, you may get motivated to lay off the carbonated drinks.
  • Food tastes better: A lot of water goes into cooking. If your water is contaminated, the taste and smell may also seep into your food. RO water has no taste, so it’s ideal for cooking.
  • No need for single-use plastic bottles: Single-use plastic bottles are a real menace to the environment. Reverse osmosis water completely eliminates the need for single-use plastic bottles since you get the water straight into your home. This is one way you can contribute to environment protection.
  • Cheaper than bottled water: For most people without an RO system, bottled water is the only source of drinking water. But buying bottled water all the time isn’t cheap. In fact, in the long run, it’s far more expensive to buy bottled water than to install and maintain an RO system.
  • Safer than bottled water: There’s the erroneous belief that all bottled water is safe. While some producers keep their bottled water at top quality, not all do. In fact, not all bottled water companies filter their water — yep, some of them sell regular tap water. RO water saves you from taking a gamble with any bottled-water brands.
  • Clear ice cubes: If you love putting ice cubes in your drinks, RO water is the best water to use. Ice cubes formed from contaminated water sometimes leave residue in drinks when contaminants melt off. You’ll never have this unpleasant experience ice cubes made with RO water.

If you have any thoughts about the question, is RO water purified water, please don’t hesitate to leave a comment below!

About the Author Gene Fitzgerald

Gene Fitzgerald is one of the founders of BOS and currently head of content creation. She has 8+ years of experience as a water treatment specialist under her belt making her our senior scientist. Outside of BOS, Gene loves reading books on philosophy & social issues, making music, and hiking.
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