What is being replaced
- Chlorine dosing that loses residual rapidly under organic load
- Peracetic acid wash systems
- Chlorine dioxide generation
Head to head
| Onsite HOCl | Quats | Chlorine / bleach | Peracetic acid | |
|---|---|---|---|---|
| Working concentration | 50–200 ppm | 200–400 ppm | 200–1,000 ppm+ | 80–200 ppm |
| pH | 5.0–6.5 | Varies | 11–13 | 2–3 |
| Skin / respiratory | Non-irritating at use conc. | Irritant, sensitiser | Irritant, fumes | Strong irritant, fumes |
| PPE burden | Minimal | Gloves, eye | Gloves, eye, ventilation | Full PPE, monitoring |
| Food-contact rinse | Not required to 200 ppm | Rinse required | Rinse required | Varies by label |
| Residue | Reverts toward salt water | Persistent film | Salt and by-products | Acetic residue |
| Biofilm | Good | Poor | Moderate | Good |
| Corrosion on stainless | Low | Low | High | High |
| Supply | Made onsite | Delivered | Delivered | Delivered, hazmat |
| Cost direction | Falls after payback | Rises | Rises | Rises |
Where the incumbents still win
Credibility requires saying this. Quaternary ammonium compounds leave a residual film that continues to act after application, which HOCl does not — where a persistent residual is genuinely wanted, that is a real advantage. Peracetic acid is more aggressive against spores at equivalent contact time. Detergents clean; HOCl does not, and no oxidiser substitutes for the mechanical removal of soil.
What onsite HOCl wins on is the bulk of routine work: cheaper per litre, safer to handle, gentler on equipment, effective across bacteria, viruses and fungi, and impossible to run out of.
Switching without disruption
Most sites transition in stages — one area, one shift or one application first, validated by swabbing, then extended. That approach also produces the internal evidence that makes the rest of the rollout straightforward to approve.