Following bleach with an alcohol sanitiser
Doing both to be thorough is the reasoning, and the two react. Hypochlorite with alcohols forms chloroform.
What is claimed
That cleaning a surface with bleach and then going over it with an alcohol-based sanitiser or wipe gives more thorough disinfection than either product alone.
Where this comes from: Widely circulated online.
Does it work?
Does not work
Refuted as a safe or effective practice on a state health department's do-not-mix list. The record is careful to state that only one read source carries the chloroform finding — that is enough to warn on, since the cost of an unnecessary rinse is nothing, and it is not enough to claim the hazard is as well documented as the chlorine reactions.
This is a verdict on whether the technique is effective. Whether it is safe on a particular surface is a separate question, answered below.
Where not to use it
Stainless steel
Best avoided
The available guidance advises against this.
Beyond the reaction, hypochlorite's chloride content attacks the passive layer on stainless steel, and the trade association advises against leaving it in contact. A surface treated this way has had bleach on it for the whole time the second product was being applied.
Precautions
- Never mix with other cleaning products
- Ventilate the area
- Rinse thoroughly afterwards
- Keep away from children and pets
Why it works
The claim assumes the two disinfectants act independently and additively, each killing what the other missed. Hypochlorite instead reacts with alcohols to produce chlorinated organic compounds including chloroform, and it does so without heating or unusual conditions. The reaction consumes both products, so the additive disinfection the technique is reaching for does not occur either. As with the acid reaction, the common route is sequential rather than simultaneous: the first product is applied, not rinsed, and the second goes onto the same wet surface — which is combining them, with the surface as the vessel.
Background
This is not a hack so much as a habit, and it became a common one: wipe a surface with bleach, then go over it with an alcohol sanitiser or wipe, on the assumption that two disinfectants are more thorough than one. Neither product is being mixed in the ordinary sense, and nobody performing it thinks of themselves as combining chemicals. A state health department hazard alert nonetheless names the pair — bleach with rubbing alcohol forms chloroform, with reported effects of dizziness, nausea, headaches and loss of consciousness. Losing consciousness in the presence of the reaction that caused it is what makes this worse than the symptom list suggests, since the exposure continues while the person cannot leave. The practical point is that isopropyl alcohol is the active ingredient in a great many surface wipes and hand rubs, so a reader can perform this without having seen the word alcohol on anything.
What it does not do
- One authoritative read source states this hazard, on a list rather than as its main subject; CleaningHQ found no second read source and records the claim at supported rather than higher for that reason
- Rinsing thoroughly between products removes the hazard, and is the answer wherever both are genuinely needed
- Disinfection requires a specified period of wet contact regardless, so a surface wiped and immediately dried has not been disinfected by either product
What to use instead
- Detergent — A surfactant-based cleaner. The general-purpose answer for greasy and particulate soil, and the correct first choice far more often than any specialist product.
- Rinsing and drying — The step people skip, and the one that decides whether cleaning protected the surface or damaged it. Residue left behind is exposure that continues after you stop.
Evidence
Does not work
Refuted as a safe or effective practice on a state health department's do-not-mix list. The record is careful to state that only one read source carries the chloroform finding — that is enough to warn on, since the cost of an unnecessary rinse is nothing, and it is not enough to claim the hazard is as well documented as the chlorine reactions.
Sources
Hazard Alert — Worker Health and Safety: Mixing Bleach with Other Cleaning Products Can Be Deadly
New Jersey Department of Health, Environmental and Occupational Health Surveillance Program · Government or regulator
Relied on for: That bleach combined with rubbing alcohol forms chloroform, with effects including dizziness, nausea, headaches and loss of consciousness. (states this directly)
Verification: a person has read the passage relied on.
Read on — Page 1, the two case reports and the bleach/ammonia and bleach/acid paragraphs; page 2, the "DANGEROUS CHEMICAL COMBINATIONS — DO NOT MIX" list and the safe-work-practices panel. Supports a wider statement — our claim was widened. The register gained authoritative support for three hazards CleaningHQ had not recorded: bleach with alcohols, hydrogen peroxide with acetic acid, and the sequential-use route evidenced by both case reports. Incompatibility records were added for the first two, and the sequential-exposure wording on the existing bleach-and-acid record now rests on a case report rather than on inference.
Cleaning methods for stainless steel
British Stainless Steel Association · Trade or professional body
Relied on for: That hypochlorite bleaches require minimal contact time on stainless steel and thorough rinsing. (states this directly)
Verification: a person has read the passage relied on.
Read on — The whole article, compared clause by clause against SSAS Information Sheet 7.20. Supports a wider statement — our claim was widened. Recorded as a dependent source, so it cannot carry a claim alone. Its overnight-bleach-soak instruction and its salt-and-vinegar caution are the specific, domestic-scale statements CleaningHQ needed and are cited alongside the information sheet rather than instead of it.
Last reviewed by a person on .
Last reviewed by a person on .