Blog › Quality Series › Chapter 2
◆ Quality Series · Part 2
In short: 75% ethanol (or 70% IPA) is not an arbitrary number — it is roughly the concentration at which alcohol kills most effectively. Holding it there is a daily control task, not a one-time setting.
Why not just use stronger alcohol?
Higher is not better. Near-pure alcohol denatures surface proteins so fast that it can flash off before it penetrates the cell, and it evaporates from the skin almost instantly. A water fraction slows evaporation and helps disrupt the cell membrane, so the alcohol keeps working long enough to do its job. Around 70–75% is the practical optimum for skin antisepsis.
75% ethanol vs 70% IPA
| Active | Notes |
|---|---|
| 75% ethanol | Common in many markets; the active in our registered prep pad. |
| 70% isopropyl alcohol (IPA) | Widely specified internationally; available on request via OEM. |
Both are well established for skin prep; the right choice depends on your market and protocol. We can supply either.
How we hold concentration in spec
- The disinfectant solution is compounded with purified water to 75% (±10% v/v).
- Concentration is verified with a calibrated alcohol meter, with readings temperature-corrected to 20 °C.
- It is checked in process on every batch and recorded in the batch record.
- The sealed barrier pouch then prevents the alcohol from evaporating, so the concentration you test at release is the concentration the user gets.
For buyers — what to ask for: confirm whether the active is ethanol or IPA and at what percentage, and ask for the measured concentration on the COA — not just the label value.
