Can I Mix It? Chemical Safety Checker.
Pick two or more substances and get a straight answer: what the combination produces, what it does to a person, and the public health source that documents it.
Which substances are going in together?
Choose two or more. Search by the name on the bottle or by the chemical — bleach, sodium hypochlorite and laundry bleach all find the same thing.
Common questions
Brand names are deliberately not matched — search by what the product is.
Every substance this checker knows
28 substances match.
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Two or more substances are needed before there is a combination to check. Choose a second one, or start from one of the common questions.
If they are already mixed
Leave the area first, then call Poison Control.
1-800-222-1222Poison Control (United States)
Free, confidential, staffed by nurses, pharmacists and toxicologists, 24 hours a day. One number reaches the poison centre for any US state or territory. It is for questions as well as emergencies — nothing has to have gone wrong yet to call it.
- Leave the room immediately and take everyone else and any animals with you.Chlorine and chloramine are heavier than air and build up fastest in small rooms with the door shut — bathrooms, laundry cupboards, under-sink spaces. Time spent doing anything else in the room is time spent breathing it.CDC / NIOSH Pocket Guide to Chemical Hazards — Chlorine(opens in a new tab)
- Get to fresh air outdoors, or to a room well away from the fumes, and stay there.Symptoms from an irritant gas can worsen for several hours after the exposure has ended, so feeling better on the way out is not evidence that the exposure was small.CDC / NIOSH Pocket Guide to Chemical Hazards — Chlorine(opens in a new tab)
- Do not try to neutralise it, pour anything else onto it, or wipe it up while it is still reacting.Adding a third product to a reaction that is already producing gas is how a bad mixture becomes a worse one. The reaction stops on its own.OSHA Occupational Chemical Database(opens in a new tab)
- Call Poison Control on 1-800-222-1222 from outside the affected area.The centre will say what the specific combination produces, what symptoms to watch for and for how long, and whether the exposure needs to be seen in person. The call is free and does not require anyone to be ill yet.HRSA Poison Help — Poison Control Centers(opens in a new tab)
- Call 911 instead if anyone is short of breath, coughing without stopping, wheezing, has chest tightness, has collapsed, or is confused.Those are signs the gas has reached the lower airway. That is an emergency response, not a phone-advice situation.America's Poison Centers(opens in a new tab)
- If it reached skin or eyes, rinse with running water for 15 to 20 minutes, removing contaminated clothing first, and call Poison Control while rinsing.Corrosive damage continues for as long as the chemical is in contact with tissue, so the length of the rinse matters more than what is rinsed with. Water is correct; a neutralising agent is not.CDC / NIOSH Pocket Guide to Chemical Hazards(opens in a new tab)
- Ventilate only once everyone is out — open windows and doors from outside the room if that can be done without breathing the fumes — and keep the room closed and unused until the smell has completely gone.Ventilation is the right end state and the wrong first move. A closed, unused room clears itself; a room being cleaned by someone holding their breath does not.CDC / NIOSH Pocket Guide to Chemical Hazards — Chlorine(opens in a new tab)
For an animal
(888) 426-4435ASPCA Animal Poison Control Center
For an animal that has walked through, licked or breathed the mixture. Open 24 hours a day; a consultation fee may apply.
ASPCA Animal Poison Control Center(opens in a new tab)How this check works
- What is checked
- Every possible pair within the selection, not just adjacent ones. Three substances are three pair look-ups; four are six. A combination is unsafe if any single pair inside it is unsafe.
- Size of the matrix
- 138 documented combinations across 28 substances, each carrying its own citation.
- How severity is handled
- Fatal, severe and corrosive combinations are refused outright — no method or recipe is produced from them anywhere in this library. Caution combinations are shown together with the reason they are flagged.
- What a clear result means
- That no reaction between the selected substances is documented in the cited sources. It is not a statement that a product is safe on a given surface, safe to breathe on its own, or safe around children and animals — those are listed separately as single-substance advisories.
- What is not covered
- Substances are matched by chemical class, not by product. A bottle whose label lists more than one active ingredient can belong to two classes at once, and a proprietary formulation can contain something not on the front of the label. Where a label is unclear, the safety data sheet for the product is the authority.
- Sources
- CDC / NIOSH Pocket Guide to Chemical Hazards, ATSDR ToxFAQs, the OSHA Occupational Chemical Database, US EPA, and the ASPCA Animal Poison Control Center. Every hazard shown links to the source it came from.
- Emergency guidance
- Poison Control, 1-800-222-1222, free and staffed 24 hours a day across the United States.Source: HRSA Poison Help — Poison Control Centers
Asked most often
The combinations people search for
Can you mix bleach and vinegar?
No. Chlorine bleach and Vinegar (acetic acid) must not be mixed: the combination produces chlorine gas. Acid liberates chlorine gas from hypochlorite bleach. Chlorine gas burns the eyes, throat and lungs, causes fluid to collect in the lungs hours after exposure, and can be fatal in an enclosed space. Anyone who has already mixed them should leave the area, get to fresh air, and call Poison Control on 1-800-222-1222.CDC / NIOSH Pocket Guide to Chemical Hazards — Chlorine(opens in a new tab)
Can you mix bleach and ammonia?
No. Chlorine bleach and Ammonia must not be mixed: the combination produces chloramine gas. Chloramine gas causes chemical burns to the airway and lungs. In an enclosed room such as a bathroom it can be fatal, and people have died cleaning with this combination. Escaping the room is the only response — the gas is heavier than air and lingers. Anyone who has already mixed them should leave the area, get to fresh air, and call Poison Control on 1-800-222-1222.CDC / NIOSH Pocket Guide to Chemical Hazards — Ammonia(opens in a new tab)
Can you mix bleach and dish soap?
No. Chlorine bleach and Dish detergent must not be mixed: the combination produces possible chloramines, depending on the detergent. Dish detergent formulations are proprietary and many contain ammonia-derived or amine-based surfactants. With bleach those release chloramine gas. The bottle does not tell you which type you have, so the combination cannot be assessed as safe. Anyone who has already mixed them should leave the area, get to fresh air, and call Poison Control on 1-800-222-1222.CDC / NIOSH Pocket Guide to Chemical Hazards — Ammonia(opens in a new tab)
Can you mix bleach and rubbing alcohol?
No. Chlorine bleach and Isopropyl alcohol must not be mixed: the combination produces chloroform, chloroacetone and hydrochloric acid. Bleach oxidises alcohol into chloroform and related chlorinated compounds. Chloroform depresses the central nervous system and damages the liver and kidneys; chloroacetone is a lachrymator that injures the eyes and airway. The reaction also produces hydrochloric acid, and the mixture can be fatal at the concentrations reached in a closed bathroom. Anyone who has already mixed them should leave the area, get to fresh air, and call Poison Control on 1-800-222-1222.ATSDR ToxFAQs — chemical fact sheets(opens in a new tab)
Can you mix vinegar and baking soda?
It is not a poisoning hazard, but it is not worth doing. Vinegar (acetic acid) and Sodium bicarbonate do not produce a hazardous gas or a violent reaction together, but the combination produces sodium acetate, water and carbon dioxide. The fizz is the two ingredients destroying each other. What is left is dilute salt water with almost no cleaning power. In a sealed bottle or a capped drain the carbon dioxide builds enough pressure to burst the container.US EPA — Safer Choice ingredient criteria(opens in a new tab)
Can you mix vinegar and hydrogen peroxide?
No. Vinegar (acetic acid) and Hydrogen peroxide must not be mixed: the combination produces peracetic acid. Peroxide and vinegar form peracetic acid. Used side by side on a surface, one after the other, this is a recognised sanitising sequence. Mixed together in a bottle and left, the concentration climbs: peracetic acid burns skin and eyes, corrodes metal and stone, and pressurises a closed container. Anyone who has already mixed them should leave the area, get to fresh air, and call Poison Control on 1-800-222-1222.US EPA — Safer Choice ingredient criteria(opens in a new tab)
The whole list
All 138 documented combinations
Every combination this checker knows about, grouped by how badly it goes wrong. Each row links to the public health source it is documented in. Selecting a combination loads it into the checker above.
| Combination | What it produces | What that does, and the source |
|---|---|---|
| Chloroform and chloroacetone, plus an ignition risk | Hypochlorite oxidises acetone into chloroform and chloroacetone by the same route it takes with rubbing alcohol, and the solvent underneath is flammable next to a solid oxidiser. Chloroform damages the liver and kidneys and chloroacetone injures the eyes and airway; in a closed room the mixture can be fatal.NOAA / EPA CAMEO Chemicals — Calcium hypochlorite(opens in a new tab) | |
| Chloroform and chloroacetone | Bleach oxidises acetone into chloroform and chloroacetone by the same route it takes with rubbing alcohol. Chloroform depresses the central nervous system and damages the liver and kidneys; chloroacetone is a lachrymator that injures the eyes and airway. In a closed bathroom the mixture can be fatal.ATSDR ToxFAQs — chemical fact sheets(opens in a new tab) | |
| Nitrogen trichloride | CAMEO records that calcium hypochlorite forms highly explosive nitrogen trichloride on contact with urea or ammonia. That is a detonation hazard on top of the chloramine gas the same pairing produces with liquid bleach, and either one can be fatal in an enclosed space. Urine and many glass cleaners both count as the ammonia side of this.NOAA / EPA CAMEO Chemicals — Calcium hypochlorite(opens in a new tab) | |
| Chloramine gas | Chloramine gas causes chemical burns to the airway and lungs. In an enclosed room such as a bathroom it can be fatal, and people have died cleaning with this combination. Escaping the room is the only response — the gas is heavier than air and lingers.CDC / NIOSH Pocket Guide to Chemical Hazards — Ammonia(opens in a new tab) | |
| Chlorine gas | Acidic drain openers are concentrated sulfuric or hydrochloric acid. On calcium hypochlorite they release chlorine gas immediately, inside a confined drain that vents straight back into the room. Chlorine gas at that concentration can be fatal.NOAA / EPA CAMEO Chemicals — Calcium hypochlorite(opens in a new tab) | |
| Chloroform and chloroacetone, and a delayed violent reaction | Hypochlorite oxidises alcohol into chloroform and related chlorinated compounds, which depress the central nervous system and damage the liver and kidneys. CAMEO adds that reactions between calcium hypochlorite and alcohols can turn violent after a delay, so nothing appearing to happen is not evidence of safety. The combination can be fatal.NOAA / EPA CAMEO Chemicals — Calcium hypochlorite(opens in a new tab) | |
| Chlorine gas | NIOSH lists chlorites and strong oxidisers as incompatible with oxalic acid, and CAMEO records that calcium hypochlorite evolves chlorine gas on contact with acids. Chlorine gas burns the eyes, throat and lungs and can be fatal in an enclosed space.NOAA / EPA CAMEO Chemicals — Calcium hypochlorite(opens in a new tab) | |
| Chlorine gas | A mineral acid on a solid hypochlorite releases chlorine gas, and calcium hypochlorite carries far more available chlorine than a bleach solution does. Chlorine gas burns the eyes, throat and lungs and can be fatal in an enclosed space.NOAA / EPA CAMEO Chemicals — Calcium hypochlorite(opens in a new tab) | |
| Chlorine gas | Acidic drain openers are concentrated sulfuric or hydrochloric acid. Poured onto bleach they release chlorine gas immediately, in a confined drain that vents straight back into the room, and the mixture boils. Chlorine gas at that concentration can be fatal.CDC / NIOSH Pocket Guide to Chemical Hazards — Chlorine(opens in a new tab) | |
| Chloroform, chloroacetone and hydrochloric acid | Bleach oxidises alcohol into chloroform and related chlorinated compounds. Chloroform depresses the central nervous system and damages the liver and kidneys; chloroacetone is a lachrymator that injures the eyes and airway. The reaction also produces hydrochloric acid, and the mixture can be fatal at the concentrations reached in a closed bathroom.ATSDR ToxFAQs — chemical fact sheets(opens in a new tab) | |
| Chlorine gas | Any acid releases chlorine gas from hypochlorite, and oxalic acid is a strong one. Chlorine gas burns the eyes, throat and lungs and can be fatal in an enclosed space. Rust removers and deck brighteners are frequently oxalic acid, so this pairing usually happens by accident rather than by choice.CDC / NIOSH Pocket Guide to Chemical Hazards — Chlorine(opens in a new tab) | |
| Chlorine gas | Any acid liberates chlorine gas from hypochlorite bleach, and phosphoric acid is a mineral acid strong enough to do it fast. Chlorine gas burns the eyes, throat and lungs, causes fluid to collect in the lungs hours later, and can be fatal in an enclosed space. Limescale removers, rust converters and acidic bathroom cleaners are frequently phosphoric acid without saying so on the front of the bottle.CDC / NIOSH Pocket Guide to Chemical Hazards — Chlorine(opens in a new tab) | |
| Chlorine gas | Citric acid liberates chlorine gas from a solid hypochlorite exactly as any other acid does, and calcium hypochlorite holds far more available chlorine than liquid bleach. Chlorine gas burns the eyes, throat and lungs and can be fatal in an enclosed space.NOAA / EPA CAMEO Chemicals — Calcium hypochlorite(opens in a new tab) | |
| Chlorine gas | Citric acid liberates chlorine gas from hypochlorite bleach exactly as vinegar does. Chlorine gas burns the eyes, throat and lungs and can be fatal in an enclosed space.CDC / NIOSH Pocket Guide to Chemical Hazards — Chlorine(opens in a new tab) | |
| Chlorine gas | This is the fastest of the hypochlorite-and-acid reactions and the one most often reached by accident, because both products sit in the same pool store. Concentrated hydrochloric acid on calcium hypochlorite granules releases chlorine gas immediately and in quantity, and chlorine gas can be fatal in an enclosed space.NOAA / EPA CAMEO Chemicals — Calcium hypochlorite(opens in a new tab) | |
| Chlorine gas | This is the fastest and most violent of the bleach-and-acid reactions: concentrated hydrochloric acid releases chlorine gas from bleach almost instantly and in quantity. Chlorine gas burns the eyes, throat and lungs and can be fatal in an enclosed space. Acidic toilet bowl cleaners and rust removers are hydrochloric acid and count as this substance.CDC / NIOSH Pocket Guide to Chemical Hazards — Chlorine(opens in a new tab) | |
| Chlorine gas | CAMEO records that calcium hypochlorite evolves highly toxic chlorine gas on contact with acids. It carries roughly ten times the available chlorine of household bleach, so the same vinegar that would be dangerous with liquid bleach is worse here. Chlorine gas burns the eyes, throat and lungs and can be fatal in an enclosed space.NOAA / EPA CAMEO Chemicals — Calcium hypochlorite(opens in a new tab) | |
| Chlorine gas | Acid liberates chlorine gas from hypochlorite bleach. Chlorine gas burns the eyes, throat and lungs, causes fluid to collect in the lungs hours after exposure, and can be fatal in an enclosed space.At higher strength: Cleaning-strength vinegar (20–30%) drives this far faster and releases far more chlorine in the first seconds. It is already fatal at table-vinegar strength; higher concentration shortens the time you have, it does not change the verdict.CDC / NIOSH Pocket Guide to Chemical Hazards — Chlorine(opens in a new tab) |
| Combination | What it produces | What that does, and the source |
|---|---|---|
| Charring, heat and flammable vapour | Concentrated acid reacts with the solvent and releases a great deal of heat next to a liquid that is flammable and whose vapour sinks toward floor level. This is an ignition risk rather than a gas risk.OSHA Occupational Chemical Database(opens in a new tab) | |
| Heat, caustic splash-back and flammable vapour | Concentrated lye heats sharply on contact with a liquid, and this liquid is flammable. A treated drain holds a caustic charge until it is flushed, so pouring solvent in can eject that charge back out of the opening.OSHA Occupational Chemical Database(opens in a new tab) | |
| Peroxide-forming mixture in a flammable solvent | Peroxide and acetone together can form organic peroxides, which are shock and heat sensitive, and the mixture remains flammable throughout. There is no cleaning task that needs both, and the pair should never be stored together after use.CDC / NIOSH Pocket Guide to Chemical Hazards(opens in a new tab) | |
| Heat, caustic splash-back and flammable vapour | Concentrated lye heats sharply on contact with a liquid, and this liquid is flammable. A treated drain holds a caustic charge until it is flushed, so pouring solvent in can eject that charge back out of the opening.OSHA Occupational Chemical Database(opens in a new tab) | |
| Peroxide-forming mixture in a flammable solvent | Sodium percarbonate releases hydrogen peroxide the moment it meets liquid, so this behaves as acetone mixed with peroxide: organic peroxides that are shock and heat sensitive, inside a flammable solvent. Applying one to a spot still wet with the other counts as mixing them.CDC / NIOSH Pocket Guide to Chemical Hazards(opens in a new tab) | |
| Violent exothermic neutralisation | Concentrated acid meeting concentrated lye releases heat fast enough to boil the mixture and blow it back out of the drain. The ejected liquid is both scalding and caustic, and can also crack the drain pipe.OSHA Occupational Chemical Database(opens in a new tab) | |
| Acid splash-back, plus total loss of enzyme activity | Concentrated acid destroys the enzymes on contact. Adding any liquid to a drain still holding an acid charge also risks that charge being displaced back out of the opening.OSHA Occupational Chemical Database(opens in a new tab) | |
| Piranha solution | Concentrated sulfuric acid with hydrogen peroxide forms piranha solution. It self-heats past boiling within seconds, oxidises skin and organic material on contact, and can detonate if any organic matter is present in quantity.OSHA Occupational Chemical Database(opens in a new tab) | |
| Charring, heat and flammable vapour | Concentrated sulfuric acid dehydrates alcohol, charring it and releasing a great deal of heat next to a flammable solvent. Alcohol vapour above a hot drain is an ignition risk.OSHA Occupational Chemical Database(opens in a new tab) | |
| Carbon dioxide and acid mist ejected from the drain | Bicarbonate in concentrated acid foams violently and the gas drives hot acid back up and out of the drain opening as a mist. Neutralising a spill on a floor with bicarbonate is a different situation from doing it inside a drain.OSHA Occupational Chemical Database(opens in a new tab) | |
| Carbon dioxide and acid mist ejected from the drain | Carbonate in concentrated acid foams violently and the gas drives hot acid back up and out of the drain opening as a mist.OSHA Occupational Chemical Database(opens in a new tab) | |
| Violent exothermic neutralisation | Concentrated acid meeting concentrated lye releases heat fast enough to boil the mixture and blow it back out of the drain. The ejected liquid is both scalding and caustic, and can also crack the drain pipe.OSHA Occupational Chemical Database(opens in a new tab) | |
| Piranha solution | Sodium percarbonate releases hydrogen peroxide, which with a concentrated sulfuric acid drain opener forms piranha solution: self-heating past boiling within seconds and oxidising skin on contact.OSHA Occupational Chemical Database(opens in a new tab) | |
| Carbon dioxide and acid mist ejected from the drain | Carbonate in concentrated acid foams violently and the gas drives hot acid back up and out of the drain opening as a mist.OSHA Occupational Chemical Database(opens in a new tab) | |
| Caustic splash-back, plus total loss of enzyme activity | Lye destroys the enzymes on contact, so the enzyme product does nothing. Pouring it into a drain still holding a caustic charge also risks that charge being displaced back out of the opening.OSHA Occupational Chemical Database(opens in a new tab) | |
| Rapid oxygen release and caustic splash-back | Strong alkali catalyses the decomposition of hydrogen peroxide. In a drain already holding a caustic charge the gas evolution forces the caustic liquid back up and out of the opening.OSHA Occupational Chemical Database(opens in a new tab) | |
| Heat, caustic splash-back and flammable vapour | Concentrated lye heats sharply the moment it meets a liquid, and the liquid here is flammable with vapour that sinks toward floor level. A treated drain holds a caustic charge until it is flushed with water, so pouring alcohol in can eject that charge back out of the opening onto skin and eyes.OSHA Occupational Chemical Database(opens in a new tab) | |
| Violent neutralisation and caustic splash-back | A concentrated acid meeting a concentrated alkali releases a great deal of heat very quickly and can eject both liquids back out of whatever is holding them. Neither is weakened usefully by the other.OSHA Occupational Chemical Database(opens in a new tab) | |
| Exothermic neutralisation and caustic splash-back | NIOSH records strong caustics as incompatible with phosphoric acid. Concentrated alkali and a mineral acid neutralise each other fast enough to boil the mixture and throw both liquids back out of whatever is holding them, scalding and caustic at the same time.CDC / NIOSH Pocket Guide to Chemical Hazards — Phosphoric acid(opens in a new tab) | |
| Rapid oxygen release and caustic splash-back | Sodium percarbonate releases hydrogen peroxide, which decomposes rapidly in the presence of strong alkali. In a treated drain the gas forces the caustic charge back out of the opening.OSHA Occupational Chemical Database(opens in a new tab) | |
| Ammonium salt fume and heat | Concentrated acid neutralising ammonia releases heat and a dense white fume of ammonium salt particles. The reaction is violent enough to spray concentrated acid out of the drain.CDC / NIOSH Pocket Guide to Chemical Hazards — Ammonia(opens in a new tab) | |
| Ammonia vapour driven off by heat | Concentrated lye is strongly alkaline and heats as it dissolves, and both of those drive dissolved ammonia out of solution as concentrated vapour straight into the room. Ammonia vapour burns the eyes and airway at concentrations below the level most people find the smell intolerable.CDC / NIOSH Pocket Guide to Chemical Hazards — Ammonia(opens in a new tab) | |
| Ammonia vapour driven off by heat | Concentrated lye is strongly alkaline and heats as it dissolves, and both of those drive dissolved ammonia out of solution as concentrated vapour straight into the room. Ammonia vapour burns the eyes and airway at concentrations below the level most people find the smell intolerable.CDC / NIOSH Pocket Guide to Chemical Hazards — Ammonia(opens in a new tab) | |
| Oxidation with heat, and an ignition risk | True soap is a fatty acid salt — organic material — and CAMEO records that calcium hypochlorite may ignite combustibles and reacts vigorously with organic matter and oils. Damp granules react faster than dry ones, which is the state a soapy surface leaves them in.NOAA / EPA CAMEO Chemicals — Calcium hypochlorite(opens in a new tab) | |
| Oxidation with heat, and an ignition risk | Detergent is organic material and calcium hypochlorite is a solid oxidiser that CAMEO records as able to ignite combustibles. Many detergents also carry amine-based surfactants, which release chloramine gas with hypochlorite. Neither risk is visible on the bottle, so the pairing cannot be assessed as safe.NOAA / EPA CAMEO Chemicals — Calcium hypochlorite(opens in a new tab) | |
| Denatured enzymes, and a chloramine or nitrogen trichloride route | Hypochlorite destroys the enzymes outright, so the cleaner stops working. Worse, enzyme cleaners are used on urine and other protein soils, and CAMEO records that calcium hypochlorite forms highly explosive nitrogen trichloride on contact with urea.NOAA / EPA CAMEO Chemicals — Calcium hypochlorite(opens in a new tab) | |
| Ignition of the oil | CAMEO records that reactions between calcium hypochlorite and organic matter, oil or hydrocarbons may lead to explosions, and that it may ignite combustibles. Pine and citrus oils are hydrocarbons: granules landing in spilled oil can start a fire with no flame present, and OSHA notes such a fire feeds itself because the granules supply their own oxygen.NOAA / EPA CAMEO Chemicals — Calcium hypochlorite(opens in a new tab) | |
| Ignition of the organic liquid | Glycerin is an organic liquid and calcium hypochlorite is a powerful solid oxidiser. CAMEO records that reactions with organic matter may lead to explosions, and OSHA that a fire involving cal hypo sustains itself because the granules liberate oxygen as they decompose.NOAA / EPA CAMEO Chemicals — Calcium hypochlorite(opens in a new tab) | |
| Oxygen gas, heat and chlorine | Hypochlorite and peroxide destroy each other in a rapid exothermic reaction that foams and can eject the mixture out of the container, and chlorine is released alongside the oxygen. With a solid hypochlorite the reaction starts where the granules sit, so the heat is concentrated rather than spread through a solution.NOAA / EPA CAMEO Chemicals — Calcium hypochlorite(opens in a new tab) | |
| Ignition of the solvent | CAMEO names hydrocarbons specifically: reactions between calcium hypochlorite and oil or hydrocarbons may lead to explosions. A petroleum distillate in contact with a solid oxidiser is an ignition risk rather than a gas risk, and no flame is needed to start it.NOAA / EPA CAMEO Chemicals — Calcium hypochlorite(opens in a new tab) | |
| Oxidised surfactant, with heat | The ethoxylate chain of a nonionic surfactant is organic and readily oxidised, and CAMEO records calcium hypochlorite as reacting with organic matter vigorously enough to be an explosion risk. The surfactant is destroyed and the heat is released against combustible material.NOAA / EPA CAMEO Chemicals — Calcium hypochlorite(opens in a new tab) | |
| Chloramines | Quaternary ammonium compounds are ammonium salts, and hypochlorite reacts with them to release chloramines — the same class of gas produced by bleach and household ammonia, from a source carrying far more available chlorine. Both products lose their disinfecting action.US EPA — What are antimicrobial pesticides?(opens in a new tab) | |
| Oxidation with heat, and an ignition risk | Saponins are plant organic matter and the dried shells are combustible. CAMEO records calcium hypochlorite as reacting vigorously with organic matter and as able to ignite combustibles such as wood, paper and clothing.NOAA / EPA CAMEO Chemicals — Calcium hypochlorite(opens in a new tab) | |
| Oxygen gas, heat and chlorine | Sodium percarbonate releases hydrogen peroxide as it dissolves, so this is the same reaction as calcium hypochlorite with liquid peroxide: rapid foaming, concentrated heat where the granules sit, and chlorine released into the room. Both products are destroyed.NOAA / EPA CAMEO Chemicals — Calcium hypochlorite(opens in a new tab) | |
| Caustic splash-back and heat | Household bleach is already stabilised with alkali, so nothing is gained chemically. The hazard is the caustic: concentrated lye heats sharply the moment it meets any liquid, and a treated drain is already hot and full of it, so adding bleach can make the charge boil and eject caustic solution back out onto skin and eyes. Nothing should go into a treated drain until it has been flushed clear.OSHA Occupational Chemical Database(opens in a new tab) | |
| Possible chloramines, depending on the detergent | Dish detergent formulations are proprietary and many contain ammonia-derived or amine-based surfactants. With bleach those release chloramine gas. The bottle does not tell you which type you have, so the combination cannot be assessed as safe.CDC / NIOSH Pocket Guide to Chemical Hazards — Ammonia(opens in a new tab) | |
| Chloramines, plus total loss of enzyme activity | Bleach denatures the enzymes outright, so the cleaner stops working. Worse, enzyme cleaners are used on urine and other protein soils, and bleach applied to urine releases chloramine gas from the urea in it.CDC / NIOSH Pocket Guide to Chemical Hazards — Ammonia(opens in a new tab) | |
| Chlorinated organic compounds | Essential oils are terpene hydrocarbons. Bleach oxidises them, producing chlorinated organic compounds and an exothermic reaction. Pine oil with bleach is a documented source of respiratory injury in cleaning workers.OSHA Occupational Chemical Database(opens in a new tab) | |
| Oxygen gas, heat and chlorine | Hypochlorite and peroxide destroy each other in a rapid exothermic reaction that foams and can eject the mixture out of the container. Chlorine is released alongside the oxygen. Neither product retains any cleaning or disinfecting power afterwards.CDC / NIOSH Pocket Guide to Chemical Hazards — Chlorine(opens in a new tab) | |
| Chlorinated hydrocarbons and heat | Hypochlorite oxidises petroleum distillates, producing chlorinated organic compounds and heat beside a flammable liquid whose vapour sinks toward floor level. Solvent and bleach steps must never share a spot or a cloth.OSHA Occupational Chemical Database(opens in a new tab) | |
| Chloramines | Quaternary ammonium compounds are ammonium salts. Bleach reacts with them to release chloramines, the same class of gas produced by bleach and household ammonia. The mixture also destroys the disinfecting action of both products.US EPA — What are antimicrobial pesticides?(opens in a new tab) | |
| Caustic splash-back and heat | Household bleach is already stabilised with alkali, so nothing is gained chemically. The hazard is the caustic: concentrated lye heats sharply the moment it meets any liquid, and a treated drain is already hot and full of it, so adding bleach can make the charge boil and eject caustic solution back out onto skin and eyes. Nothing should go into a treated drain until it has been flushed clear.OSHA Occupational Chemical Database(opens in a new tab) | |
| Oxygen gas, heat and chlorine | Sodium percarbonate releases hydrogen peroxide as it dissolves, so this is the same reaction as bleach with liquid peroxide: rapid foaming, heat, and chlorine released into the room. Both products are destroyed.CDC / NIOSH Pocket Guide to Chemical Hazards — Chlorine(opens in a new tab) | |
| Exothermic neutralisation and caustic splash-back | Any acid neutralises concentrated lye violently, and NIOSH records acids as incompatible with it. In a treated drain the heat boils the standing liquid and throws caustic back out of the opening; on a treated oven surface it spatters hot caustic.OSHA Occupational Chemical Database(opens in a new tab) | |
| Exothermic neutralisation and caustic splash-back | Any acid neutralises concentrated lye violently, and NIOSH records acids as incompatible with it. In a treated drain the heat boils the standing liquid and throws caustic back out of the opening; on a treated oven surface it spatters hot caustic.OSHA Occupational Chemical Database(opens in a new tab) | |
| Acid foam ejected from the drain | Detergent turns the hot acid standing in the drain into foam, which expands and rises out of the opening, carrying concentrated acid onto surrounding surfaces and onto anyone leaning over the drain.OSHA Occupational Chemical Database(opens in a new tab) | |
| Caustic foam | Detergent turns hot caustic liquid into foam that expands and spreads well past where it was poured. In a treated drain it rises back out of the opening, carrying concentrated lye onto surrounding surfaces and onto anyone leaning over it. The soap adds no cleaning power the lye does not already have.OSHA Occupational Chemical Database(opens in a new tab) | |
| Caustic foam | Detergent turns hot caustic liquid into foam that expands and spreads well past where it was poured. In a treated drain it rises back out of the opening, carrying concentrated lye onto surrounding surfaces and onto anyone leaning over it. The soap adds no cleaning power the lye does not already have.OSHA Occupational Chemical Database(opens in a new tab) | |
| Caustic splash-back, plus total loss of enzyme activity | Lye destroys the enzymes on contact, so the enzyme product does nothing. Pouring it into a drain still holding a caustic charge also risks that charge being displaced back out of the opening.OSHA Occupational Chemical Database(opens in a new tab) | |
| Rapid oxygen release and caustic splash-back | Strong alkali catalyses the decomposition of hydrogen peroxide. In a drain already holding a caustic charge the gas evolution forces the caustic liquid back up and out of the opening.OSHA Occupational Chemical Database(opens in a new tab) | |
| Heat, caustic splash-back and flammable vapour | Concentrated lye heats sharply the moment it meets a liquid, and the liquid here is flammable with vapour that sinks toward floor level. A treated drain holds a caustic charge until it is flushed with water, so pouring alcohol in can eject that charge back out of the opening onto skin and eyes.OSHA Occupational Chemical Database(opens in a new tab) | |
| Violent exothermic neutralisation | Concentrated hydrochloric acid neutralising concentrated lye releases heat fast enough to boil and eject the mixture. The spray is scalding, caustic and acidic at the same time.OSHA Occupational Chemical Database(opens in a new tab) | |
| Ammonium chloride fume and heat | Hydrochloric acid and ammonia produce a dense white fume of ammonium chloride particles, along with enough heat to spatter the concentrated acid. The fume irritates the eyes and airway and obscures vision.CDC / NIOSH Pocket Guide to Chemical Hazards — Ammonia(opens in a new tab) | |
| Chlorine gas | Hydrogen peroxide oxidises hydrochloric acid and releases chlorine gas. Chlorine gas burns the eyes, throat and lungs and can be fatal in an enclosed space.CDC / NIOSH Pocket Guide to Chemical Hazards — Chlorine(opens in a new tab) | |
| Violent exothermic neutralisation | Concentrated hydrochloric acid neutralising concentrated lye releases heat fast enough to boil and eject the mixture. The spray is scalding, caustic and acidic at the same time.OSHA Occupational Chemical Database(opens in a new tab) | |
| Chlorine gas | Sodium percarbonate releases hydrogen peroxide, which oxidises hydrochloric acid and liberates chlorine gas. Chlorine gas burns the eyes, throat and lungs.CDC / NIOSH Pocket Guide to Chemical Hazards — Chlorine(opens in a new tab) | |
| Violent neutralisation and caustic splash-back | A concentrated acid meeting a concentrated alkali releases a great deal of heat very quickly and can eject both liquids back out of whatever is holding them. Neither is weakened usefully by the other.OSHA Occupational Chemical Database(opens in a new tab) | |
| Exothermic neutralisation and caustic splash-back | NIOSH records strong caustics as incompatible with phosphoric acid. Concentrated alkali and a mineral acid neutralise each other fast enough to boil the mixture and throw both liquids back out of whatever is holding them, scalding and caustic at the same time.CDC / NIOSH Pocket Guide to Chemical Hazards — Phosphoric acid(opens in a new tab) | |
| Rapid oxygen release and caustic splash-back | Sodium percarbonate releases hydrogen peroxide, which decomposes rapidly in the presence of strong alkali. In a treated drain the gas forces the caustic charge back out of the opening.OSHA Occupational Chemical Database(opens in a new tab) | |
| Exothermic neutralisation and caustic splash-back | NIOSH lists acids as incompatible with sodium hydroxide: the neutralisation is violent and releases a great deal of heat at once. Poured onto a caustic drain charge it can boil the standing liquid and throw concentrated lye back out of the opening; sprayed onto an oven surface still wet with cleaner it spatters hot caustic at head height.OSHA Occupational Chemical Database(opens in a new tab) | |
| Exothermic neutralisation and caustic splash-back | NIOSH lists acids as incompatible with sodium hydroxide: the neutralisation is violent and releases a great deal of heat at once. Poured onto a caustic drain charge it can boil the standing liquid and throw concentrated lye back out of the opening; sprayed onto an oven surface still wet with cleaner it spatters hot caustic at head height.OSHA Occupational Chemical Database(opens in a new tab) |
| Combination | What it produces | What that does, and the source |
|---|---|---|
| Peracetic acid | Peroxide and vinegar form peracetic acid. Used side by side on a surface, one after the other, this is a recognised sanitising sequence. Mixed together in a bottle and left, the concentration climbs: peracetic acid burns skin and eyes, corrodes metal and stone, and pressurises a closed container.At higher strength: With 3% peroxide and table vinegar this is a slow, mildly corrosive mixture. Above roughly 10% peroxide, or with 20–30% vinegar, peracetic acid forms fast enough to burn skin and airways on contact and the reaction gives off real heat.US EPA — Safer Choice ingredient criteria(opens in a new tab) | |
| Peracetic acid | Sodium percarbonate releases hydrogen peroxide, which with vinegar forms peracetic acid. Stored in a closed bottle the concentration climbs; peracetic acid burns skin and eyes and corrodes metal and stone. The acid also neutralises the carbonate, so the powder loses its cleaning action.At higher strength: Percarbonate releases peroxide as it dissolves, so the same escalation applies: with cleaning-strength vinegar this stops being a fizz and becomes a hot, corrosive mixture.US EPA — Safer Choice ingredient criteria(opens in a new tab) |
| Combination | What it produces | What that does, and the source |
|---|---|---|
| Decomposed peroxide | Alkaline conditions accelerate the breakdown of hydrogen peroxide into water and oxygen, so the peroxide is spent before it can do anything. At household strengths the reaction is not violent, but nothing is gained by it.CDC / NIOSH Pocket Guide to Chemical Hazards(opens in a new tab) | |
| Ammonium oxalate | The alkali and the acid neutralise each other and both stop working, leaving a salt solution with no cleaning power. Ammonia vapour is released as the mixture warms.CDC / NIOSH Pocket Guide to Chemical Hazards — Ammonia(opens in a new tab) | |
| Ammonium phosphate, with heat | The acid neutralises the ammonia and both are consumed, leaving a salt solution with no cleaning power. The reaction warms as it goes and drives ammonia vapour out of solution while it does.CDC / NIOSH Pocket Guide to Chemical Hazards — Ammonia(opens in a new tab) | |
| Decomposed peroxide | The released hydrogen peroxide breaks down quickly under alkaline conditions, so the oxygen bleaching action is lost before it reaches the stain.CDC / NIOSH Pocket Guide to Chemical Hazards(opens in a new tab) | |
| Chlorine and heat as the granules dissolve | Bleach is mostly water, and CAMEO records that calcium hypochlorite is slowly decomposed by water with the evolution of gaseous chlorine and heat. Combining the two puts an uncontrolled amount of available chlorine in one container for no gain, and the granules should be dissolved in water alone instead.NOAA / EPA CAMEO Chemicals — Calcium hypochlorite(opens in a new tab) | |
| Oxidised soap | Bleach oxidises the fatty acid salts that make up true soap. The soap loses its cleaning power and the bleach is partly spent on the soap rather than on the surface. Castile soap has a known, simple composition, so this combination does not carry the gas risk that bleach with a proprietary detergent does — but there is still no reason to mix them.CDC / NIOSH Pocket Guide to Chemical Hazards — Chlorine(opens in a new tab) | |
| Free fatty acids — a white curd | Acid converts true soap back into fatty acids, producing a curd that films the surface rather than cleaning it. On a deck this leaves a grey film exactly where the brightener was supposed to work.US EPA — Safer Choice ingredient criteria(opens in a new tab) | |
| Free fatty acids — a white curd | Acid converts true soap back into the fatty acids it was made from. The result is a white curd that leaves a film on whatever it is wiped over, and no cleaning happens. Use the acid and the soap as separate steps with a rinse between them.US EPA — Safer Choice ingredient criteria(opens in a new tab) | |
| Deactivated disinfectant and soap curd | True soap is anionic and binds the cationic disinfectant, precipitating both as a curd. The disinfectant no longer meets its registered kill claim.US EPA — What are antimicrobial pesticides?(opens in a new tab) | |
| Partly degraded surfactant | Bleach attacks the ethoxylate chain of a nonionic surfactant over time. Commercial bleach cleaners use surfactants selected for stability; adding an ordinary one to bleach reduces both.CDC / NIOSH Pocket Guide to Chemical Hazards — Chlorine(opens in a new tab) | |
| Oxidised saponins | Bleach oxidises the saponins and both are consumed. The wash gets neither the surfactant nor the full bleaching action.CDC / NIOSH Pocket Guide to Chemical Hazards — Chlorine(opens in a new tab) | |
| Ammonium citrate | The acid neutralises the ammonia, consuming both. Ammonia vapour is released as the mixture warms.CDC / NIOSH Pocket Guide to Chemical Hazards — Ammonia(opens in a new tab) | |
| Boric acid in solution | Citric acid converts borate to boric acid and removes the alkalinity that borax contributes, so the laundry-boosting effect is lost.US EPA — Safer Choice ingredient criteria(opens in a new tab) | |
| Free fatty acids — a white curd | Citric acid converts true soap back into fatty acids, producing a curd that leaves a film rather than cleaning. Use the acid and the soap in separate steps instead.US EPA — Safer Choice ingredient criteria(opens in a new tab) | |
| Denatured enzymes | Citric acid takes the solution below the pH range the enzymes need and they stop working immediately. This matters most on pet urine, where the enzyme step is the only thing that removes the odour rather than masking it.US EPA — Safer Choice ingredient criteria(opens in a new tab) | |
| Peroxycitric acid | An acid added to peroxide forms a peroxy acid. Peroxycitric acid is far weaker than the peracetic acid formed with vinegar, but the mixture still loses its oxidising strength on standing and pressurises a closed container.US EPA — Safer Choice ingredient criteria(opens in a new tab) | |
| Disinfectant taken outside its registered pH | Citric acid drops the solution below the pH band the disinfectant was registered and tested at, so its kill claim no longer applies. Nothing visible changes, which is what makes it worth knowing.US EPA — What are antimicrobial pesticides?(opens in a new tab) | |
| Sodium citrate, water and carbon dioxide | The two neutralise each other and stop working. The fizz is useful for lifting loose debris mechanically, but nothing is being cleaned chemically once the reaction finishes.US EPA — Safer Choice ingredient criteria(opens in a new tab) | |
| Sodium citrate, water and carbon dioxide | The acid neutralises the alkali and both are consumed. In a sealed container the carbon dioxide builds enough pressure to burst it.US EPA — Safer Choice ingredient criteria(opens in a new tab) | |
| Peroxycitric acid, and loss of the alkaline builder | Citric acid neutralises the carbonate that sodium percarbonate needs to work, so the powder stops lifting stains. The peroxy acid formed is weak, but the mixture should not be kept in a closed bottle.US EPA — Safer Choice ingredient criteria(opens in a new tab) | |
| Sodium citrate, water and carbon dioxide | The acid neutralises the alkali and both are consumed. In a sealed container the carbon dioxide builds enough pressure to burst it.US EPA — Safer Choice ingredient criteria(opens in a new tab) | |
| Deactivated disinfectant | Quaternary ammonium compounds carry a positive charge; the anionic surfactants in most dish detergents carry a negative one. They bind to each other and precipitate, so the disinfectant no longer meets its registered kill claim even though the mixture still looks and foams like a cleaner.US EPA — What are antimicrobial pesticides?(opens in a new tab) | |
| Denatured enzymes | Peroxide oxidises the enzymes and stops them working. If both are wanted, the enzyme treatment has to run to completion and be rinsed out before the peroxide goes on.US EPA — Safer Choice ingredient criteria(opens in a new tab) | |
| Denatured enzymes | Oxalic acid takes the solution below the pH range the enzymes need and they stop working immediately. Nothing visible changes, which is what makes it worth knowing before the step is wasted.US EPA — Safer Choice ingredient criteria(opens in a new tab) | |
| Denatured enzymes | Enzymes work only inside a narrow pH range and a mineral acid takes the solution well below it. The enzyme product stops working the moment the acid goes in, with no visible sign that it has.US EPA — Safer Choice ingredient criteria(opens in a new tab) | |
| Denatured enzymes | Quaternary ammonium compounds denature proteins, which is how they kill bacteria and also what they do to the enzymes in an enzyme cleaner. Used together, the enzyme product stops working.US EPA — What are antimicrobial pesticides?(opens in a new tab) | |
| Denatured enzymes | The peroxide released by sodium percarbonate denatures the enzymes. Run the enzyme step first, rinse, then use the oxygen bleach.US EPA — Safer Choice ingredient criteria(opens in a new tab) | |
| Oxidised terpenes | Peroxide oxidises the terpenes in essential oils, destroying both the scent and the peroxide. Oxidised terpenes are also a more common skin sensitiser than the fresh oil.US EPA — Safer Choice ingredient criteria(opens in a new tab) | |
| Oxidised terpenes | The hydrogen peroxide released by sodium percarbonate oxidises the oil, so the scent is gone before the wash finishes and some of the bleaching power is spent on the oil.US EPA — Safer Choice ingredient criteria(opens in a new tab) | |
| A flammable mixture that weakens both ingredients | Peroxide slowly oxidises the alcohol, so both are consumed and neither remains at the strength its label states. The mixture stays flammable while gaining nothing: alcohol below roughly 60 per cent does not disinfect, and peroxide is not made stronger by being diluted into it. Stored together in a closed bottle the pair also concentrates an oxidiser against a flammable solvent, which is a fire risk rather than a gas risk.CDC / NIOSH Pocket Guide to Chemical Hazards(opens in a new tab) | |
| An oxidiser sitting in a flammable solvent | Neither is made more effective by the other, and the pair leaves an oxidiser in contact with a flammable petroleum distillate. Let a solvent step dry fully before any oxygen-bleach step touches the same spot.CDC / NIOSH Pocket Guide to Chemical Hazards(opens in a new tab) | |
| Two products spending themselves on each other | NIOSH lists strong oxidisers as incompatible with oxalic acid. Peroxide oxidises the acid, so a deck brightener and an oxygen bleach used wet-on-wet consume each other and neither reaches full strength on the timber. Let one step dry and rinse before the other starts.CDC / NIOSH Pocket Guide to Chemical Hazards — Oxalic acid(opens in a new tab) | |
| A flammable mixture that weakens both ingredients | Sodium percarbonate releases hydrogen peroxide as soon as it meets liquid, so this behaves as alcohol mixed with peroxide. Both are consumed, neither ends up at label strength, and an oxidiser is left sitting in a flammable solvent. Keep the powder away from alcohol and dissolve it in water alone.CDC / NIOSH Pocket Guide to Chemical Hazards(opens in a new tab) | |
| An oxidiser sitting in a flammable solvent | Sodium percarbonate releases hydrogen peroxide in water, so this is an oxidiser left in contact with a flammable petroleum distillate. Let the solvent flash off completely before the oxygen-bleach step.CDC / NIOSH Pocket Guide to Chemical Hazards(opens in a new tab) | |
| Denatured enzymes | Strong acid destroys the enzymes on contact. There is no combination of the two that does anything useful.OSHA Occupational Chemical Database(opens in a new tab) | |
| Carbon dioxide, heat and acid mist | Bicarbonate is the standard neutraliser for an acid spill, but adding it to concentrated acid foams hard and throws a fine acid mist. Add it slowly, in small amounts, from upwind, and never inside a closed container.OSHA Occupational Chemical Database(opens in a new tab) | |
| Carbon dioxide, heat and acid mist | Carbonate neutralises the acid, but does so vigorously: it foams and throws a fine acid mist. Add it slowly and in small amounts, never inside a closed container.OSHA Occupational Chemical Database(opens in a new tab) | |
| Carbon dioxide, heat and acid mist | Carbonate neutralises the acid, but does so vigorously: it foams and throws a fine acid mist. Add it slowly and in small amounts, never inside a closed container.OSHA Occupational Chemical Database(opens in a new tab) | |
| Diluted disinfectant | Nonionic surfactants do not neutralise quats and are used alongside them in commercial formulations, but adding any extra liquid to a ready-to-use disinfectant drops the active ingredient below the concentration its EPA registration is based on.US EPA — What are antimicrobial pesticides?(opens in a new tab) | |
| Carbon dioxide and a spent acid | The bicarbonate neutralises the acid on contact, so the mixture fizzes and then does nothing. Whatever the acid was meant to lift is left behind, with no visible sign that the product has been cancelled.US EPA — Safer Choice ingredient criteria(opens in a new tab) | |
| Carbon dioxide and a spent acid | Carbonate neutralises the acid and both are consumed. The rust or tannin stain the acid was meant to lift is left in place, and in a sealed container the carbon dioxide builds enough pressure to burst it.US EPA — Safer Choice ingredient criteria(opens in a new tab) | |
| Two products spending themselves on each other | Sodium percarbonate releases hydrogen peroxide as it dissolves, and NIOSH lists strong oxidisers as incompatible with oxalic acid. The acid also neutralises the carbonate the powder needs to work, so both the brightener and the oxygen bleach end up weaker than either alone.CDC / NIOSH Pocket Guide to Chemical Hazards — Oxalic acid(opens in a new tab) | |
| Carbon dioxide and a spent acid | Carbonate neutralises the acid and both are consumed. The rust or tannin stain the acid was meant to lift is left in place, and in a sealed container the carbon dioxide builds enough pressure to burst it.US EPA — Safer Choice ingredient criteria(opens in a new tab) | |
| Carbon dioxide and a spent acid | The bicarbonate neutralises the acid on contact. The mixture fizzes, then does nothing: the scale or rust the acid was meant to lift is left in place, with no visible sign that the product has been cancelled.US EPA — Safer Choice ingredient criteria(opens in a new tab) | |
| Carbon dioxide and a spent acid | Carbonate neutralises the acid and both are consumed. In a sealed container the carbon dioxide builds enough pressure to burst it, and nothing is descaled either way.US EPA — Safer Choice ingredient criteria(opens in a new tab) | |
| Carbon dioxide and a spent acid | Carbonate neutralises the acid and both are consumed. In a sealed container the carbon dioxide builds enough pressure to burst it, and nothing is descaled either way.US EPA — Safer Choice ingredient criteria(opens in a new tab) | |
| Reduced disinfectant activity | Saponins are surface-active and bind quaternary ammonium compounds, reducing the concentration of free disinfectant below the level its label claim depends on.US EPA — What are antimicrobial pesticides?(opens in a new tab) | |
| Ammonium acetate | The alkali and the acid neutralise each other. Both stop working and the result is a salt solution with no cleaning power. The reaction also warms and releases ammonia vapour as it goes.CDC / NIOSH Pocket Guide to Chemical Hazards — Ammonia(opens in a new tab) | |
| Boric acid in solution | Vinegar converts borate to boric acid and removes the alkalinity that borax contributes. The mixture no longer softens water or boosts detergent.US EPA — Safer Choice ingredient criteria(opens in a new tab) | |
| Free fatty acids — a white curd | Acid converts true soap back into the fatty acids it was made from. The result is a white curd that leaves a film on whatever it is wiped over, and no cleaning happens. This is the most common failure in homemade cleaner recipes.US EPA — Safer Choice ingredient criteria(opens in a new tab) | |
| Reduced detergency, and precipitate in hard water | Detergent works best at neutral to alkaline pH; vinegar pushes the mixture acidic and cuts its grease-cutting power. In hard water the acid also drops the calcium out of solution as a visible film.US EPA — Safer Choice ingredient criteria(opens in a new tab) | |
| Denatured enzymes | Enzymes work only inside a narrow pH range and vinegar takes the solution below it. The product stops working from the moment the acid goes in, with no visible sign that it has. If both are needed, use the enzyme cleaner first and let it dry fully before any acid step.US EPA — Safer Choice ingredient criteria(opens in a new tab) | |
| Disinfectant taken outside its registered pH | Quaternary ammonium products are registered at one concentration and one pH band, and acidifying the solution takes it outside the conditions its kill claim was tested under. The danger is quiet: the surface is left wet and apparently disinfected when it has not been.US EPA — What are antimicrobial pesticides?(opens in a new tab) | |
| Hydrolysed saponins | Acid breaks down the saponins that make soap nuts work, so foam and cleaning power drop. Vinegar is better added to the rinse than to the wash.US EPA — Safer Choice ingredient criteria(opens in a new tab) | |
| Sodium acetate, water and carbon dioxide | The fizz is the two ingredients destroying each other. What is left is dilute salt water with almost no cleaning power. In a sealed bottle or a capped drain the carbon dioxide builds enough pressure to burst the container.US EPA — Safer Choice ingredient criteria(opens in a new tab) | |
| Sodium acetate, water and carbon dioxide | The acid neutralises the alkali. Both are consumed and the result is dilute salt water. In a sealed container the carbon dioxide builds enough pressure to burst it.US EPA — Safer Choice ingredient criteria(opens in a new tab) | |
| Sodium acetate, water and carbon dioxide | The acid neutralises the alkali. Both are consumed and the result is dilute salt water. In a sealed container the carbon dioxide builds enough pressure to burst it.US EPA — Safer Choice ingredient criteria(opens in a new tab) |
Other tools
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