Skip to content

Chemical collection and stock control for UK schools, universities and hospitals

Barium peroxide (CAS 1304-29-6): storage and disposal

Barium peroxide is a greyish white powder that mostly survives as legacy stock in school, college and university stores. It is an oxidiser that may intensify a fire, and a harmful barium compound if swallowed or inhaled. The condition of old stock is unpredictable, and that is what decides its handling. It is not quoted online, and each holding goes through a manual enquiry and an assessment.

CAS number
1304-29-6
Form
Solid
Storage class
Oxidiser
Signal word
Danger
Usual EWC code
16 05 06*
  • Oxidising pictogramOxidising
  • Harmful or irritant pictogramHarmful or irritant

This chemical is a manual enquiry

This can become unstable or explosive, especially if it is old or has dried out. Nobody should move it until someone competent has looked at it, so we start with a conversation and usually a store assessment.

Strong oxidiser legacy stock: unpredictable condition.

It cannot be priced through a form. Please do not open or move it. Call us or send an enquiry and we will talk through the safe next step, which is often a store assessment.

What to do this week

  1. Leave it where it is. If it looks old, crystalline or damaged, do not open or move it and keep people away from the shelf.
  2. Write down the label wording, the rough age and where it is stored, from a safe distance.
  3. Send us those details, and a photo if you can take one without touching it.

Safe storage in a school or lab

Check the lid first: is it sound and closed, and is the shelf around it dry? Moisture and carbon dioxide slowly change this powder, and an oxidiser with a poor seal is more of a problem than one that has been left undisturbed. Its place is the separate oxidiser space, on non-combustible shelving, with flammable and corrosive stock elsewhere. Acid needs particular distance, because acids release hydrogen peroxide from it. Old school stores sometimes keep it beside barium salts simply because of the name, but this one is an oxidiser and should not be grouped by metal. Paper and wood in contact with it are a fire concern. If a jar is damaged or has no date, leave it there and do not open it.

How to tell it has deteriorated

Over a long time, moisture and carbon dioxide from the air turn the surface of this powder into barium hydroxide and carbonate. That shows as a white crust or a hard, caked layer on what was a greyish white powder, so old stock may be a mixture of unknown strength. Because reaction with water can release oxygen, a slightly swollen container is possible and should be treated seriously. Corroded caps, staining on the shelf and paper or organic dust around the jar are the other findings to note. Beyond that it gives few distinctive signs, and looks are no guide to how reactive it remains. Do not break up a crust or open the jar to look inside it. Describe it from outside.

How it must be disposed of

This does not go through our standard collection route. It is arranged by manual enquiry, and never goes down the drain or into general waste.

It leaves after a manual enquiry, because legacy stock like this is of unpredictable condition and it is not quoted online. The online quote path does not accept it. A store assessment is recommended, with a competent chemist seeing it in person, and warning signs may call for an explosives or emergency specialist. Tell them what the label says, roughly how old the jar is, and whether you can see any crust, swelling or staining. Since it is both an oxidiser and a harmful barium compound, say what stands around it. Do not open it, move it or try to make it safe in the meantime. It must never go into a sink, a drain, a bin or a skip. School stock normally takes code 16 05 06*.

Waste codes and transport details for Barium peroxide
EWC code, laboratory chemicals16 05 06*
Discarded inorganic chemical, not a laboratory pack16 05 07*
Hazardous wasteYes

The code depends on where the waste came from and what it is mixed with. Use the waste code finder to see why.

Do not store with

  • FlammableOxidisers can ignite flammable materials or make a fire far more intense.
  • AcidMany oxidisers release toxic gas or become unstable in contact with acid.
  • AlkaliSome oxidisers react strongly with alkalis, and ammonia based stock is especially at risk.
  • ToxicToxic and oxidising stock are stored apart. A reaction could release toxic vapours.
  • CorrosiveCorrosive stock can react with oxidisers, releasing heat or fumes.

Named chemicals to keep apart

  • Acetic acidMany oxidisers release toxic gas or become unstable in contact with acid.
  • AcetoneOxidisers can ignite flammable materials or make a fire far more intense.
  • Ammonia solutionSome oxidisers react strongly with alkalis, and ammonia based stock is especially at risk.
  • EthanolOxidisers can ignite flammable materials or make a fire far more intense.
  • FormalinToxic and oxidising stock are stored apart. A reaction could release toxic vapours.
  • HexaneOxidisers can ignite flammable materials or make a fire far more intense.
  • Hydrochloric acidMany oxidisers release toxic gas or become unstable in contact with acid.
  • Mercury(II) chlorideToxic and oxidising stock are stored apart. A reaction could release toxic vapours.
Show 9 more
  • MethanolOxidisers can ignite flammable materials or make a fire far more intense.
  • Nitric acidMany oxidisers release toxic gas or become unstable in contact with acid.
  • Potassium hydroxideSome oxidisers react strongly with alkalis, and ammonia based stock is especially at risk.
  • Sodium cyanideToxic and oxidising stock are stored apart. A reaction could release toxic vapours.
  • Sodium hydroxideSome oxidisers react strongly with alkalis, and ammonia based stock is especially at risk.
  • Sulfuric acidMany oxidisers release toxic gas or become unstable in contact with acid.
  • Thionyl chlorideCorrosive stock can react with oxidisers, releasing heat or fumes.
  • TolueneOxidisers can ignite flammable materials or make a fire far more intense.
  • Zinc chlorideCorrosive stock can react with oxidisers, releasing heat or fumes.

Common quantities we collect

Usually held as: legacy stock.

Part-used bottles and full containers are both fine. Tell us the size and how many, and an estimate is enough for a first price.

Where it is commonly held

Hazard statements

  • H272 May intensify fire; oxidiser.
  • H302 Harmful if swallowed.
  • H332 Harmful if inhaled.
Precautionary statements
  • P210 Keep away from heat, hot surfaces, sparks, open flames and other ignition sources. No smoking.
  • P220 Keep away from clothing and other combustible materials.
  • P261 Avoid breathing dust, fume, gas, mist, vapours or spray.
  • P264 Wash hands and exposed skin thoroughly after handling.
  • P270 Do not eat, drink or smoke when using this product.
  • P271 Use only outdoors or in a well-ventilated area.
  • P280 Wear protective gloves, protective clothing, eye protection and face protection.
  • P301+P317 IF SWALLOWED: Get medical help.
  • P304+P340 IF INHALED: Remove person to fresh air and keep comfortable for breathing.
  • P317 Get medical help.
  • P330 Rinse mouth.
  • P370+P378 In case of fire: Use suitable extinguishing media to extinguish.
  • P501 Dispose of contents and container in accordance with local, regional, national and international regulations.

Substance as classified, dilutions may differ.

Questions

Can it go in with our other barium salts for collection?

It should not simply be listed with them. Barium peroxide is an oxidiser as well as a barium compound, and it is not quoted online. Send a manual enquiry for this jar, and list any other barium salts separately so that each can be assessed correctly.

A hard crust has formed on the powder. Does that make it less hazardous?

You should not assume so. The crust is hydroxide and carbonate formed by moist air, and peroxide can remain underneath. Nobody can judge the strength of the contents by looking. Leave the jar closed and mention the crust in your enquiry.

How do we describe a jar with no date on it?

Say that the date is missing, then give whatever else you can: the supplier name on the label, the style of the container, and where it has been stored. Old packaging can help a chemist estimate its age. Leave the jar where it is while you do this.

Guidance only. Check your own risk assessment and your supplier's safety data sheet.

Hazard data source: PubChem GHS Classification, retrieved 31 Oct 2026. Formula BaO2. EC number 215-128-4.

Manual enquiry Add to register
Search the chemical database