Ammonium chloride (CAS 12125-02-9): storage and disposal
Ammonium chloride is a white crystalline salt that school, college, university and pathology stores hold as a plain tub of solid. It is classified as harmful if swallowed and as causing serious eye irritation, with a Warning signal word. On the shelf, the question is its neighbours: bleaches, chlorates and strong alkalis all react with ammonium salts.
- CAS number
- 12125-02-9
- Form
- Solid
- Storage class
- General
- Signal word
- Warning
- Usual EWC code
- 16 05 06*
Harmful or irritant
What to do this week
- Check the label is readable and write down the opened date if it is not already there.
- Check it is stored as general stock and apart from the items listed under "Do not store with".
- If you no longer need it, add it to your disposal list so it goes on the next collection.
Safe storage in a school or lab
Usually a plastic tub of white crystals or granules, it should be kept away from hypochlorites and chlorine releasing stock, since those form toxic gas with ammonium compounds, and from chlorates, which can give unstable ammonium chlorate. Sodium and potassium hydroxide also stay apart, because a strong alkali frees ammonia from an ammonium salt. A school prep room should keep ammonium chloride separate from bleach and caustic bottles. If a container is leaking or contamination is suspected, leave it undisturbed and arrange a specialist assessment before relocation. Otherwise a dry, labelled, well organised store is enough, with eye protection for scooping and the lid closed afterwards.
How to tell it has deteriorated
Look at the condition of the tub and label first. A good tub holds loose, dry, white crystals. Damp air makes them cake into a hard lump, and a lid left off lets in dust and moisture. The salt gives few distinctive signs of age, so check for a crusted neck, a cracked tub, a faded or lifted label and no date of receipt. A sharp ammonia smell on opening is not normal for this salt, and suggests it has met an alkali. Do not handle or attempt to close a suspect container. Leave it undisturbed and report the suspected ammonia release for specialist assessment.
How it must be disposed of
By specialist collection only. It never goes down the drain or into general waste. It is normally packed in a non-regulated or low hazard laboratory pack with compatible chemicals.
What to record before asking for a collection: the size of the container, how much is left, its condition, and what stands next to it. Waste code 16 05 06* is the usual entry, and a pathology lab in human healthcare would use 18 01 06*. Packed in a lab pack with compatible solids, it is kept away from hypochlorites, chlorates and strong alkalis, the same neighbours it avoids on the shelf. It is never a sink, drain, general waste or skip item, and staff should not try to treat it first.
| EWC code, laboratory chemicals | 16 05 06* |
|---|---|
| Discarded inorganic chemical, not a laboratory pack | 16 05 07* |
| Human healthcare setting | 18 01 06* |
| Hazardous waste | Yes |
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
Named chemicals to keep apart
- Calcium hypochloriteHypochlorites and ammonia or amines form toxic chloramine gases.
- Chloramine THypochlorites and ammonia or amines form toxic chloramine gases.
- Potassium chlorateChlorates and ammonium salts can form unstable ammonium chlorate.
- Potassium hydroxideStrong alkalis release ammonia gas from ammonium salts.
- Sodium chlorateChlorates and ammonium salts can form unstable ammonium chlorate.
- Sodium dichloroisocyanurateHypochlorites and ammonia or amines form toxic chloramine gases.
- Sodium hydroxideStrong alkalis release ammonia gas from ammonium salts.
- Sodium hypochloriteHypochlorites and ammonia or amines form toxic chloramine gases.
Show 1 more
- Sodium nitriteNitrites and ammonium salts can react violently on heating.
Common quantities we collect
Usually held as: solid.
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
- H302 Harmful if swallowed.
- H319 Causes serious eye irritation.
Precautionary statements
- P264 Wash hands and exposed skin thoroughly after handling.
- P264+P265 Wash hands and exposed skin thoroughly after handling. Do not touch eyes.
- P270 Do not eat, drink or smoke when using this product.
- P280 Wear protective gloves, protective clothing, eye protection and face protection.
- P301+P317 IF SWALLOWED: Get medical help.
- P305+P351+P338 IF IN EYES: Rinse cautiously with water for several minutes. Remove contact lenses, if present and easy to do. Continue rinsing.
- P330 Rinse mouth.
- P337+P317 If eye irritation persists: Get medical help.
- P501 Dispose of contents and container in accordance with local, regional, national and international regulations.
Substance as classified, dilutions may differ.
Questions
Why keep ammonium chloride away from bleach?
Hypochlorites and ammonia or amines form toxic chloramine gases, and the same warning covers chlorine releasing disinfectants. Keep the salt on a separate shelf from bleach, chlorine tablets and chlorates.
Which hazards apply to it?
It is harmful if swallowed and causes serious eye irritation, with a Warning signal word. Use eye protection when scooping, and keep the lid closed and the tub away from food and drink.
Why does the tub smell of ammonia?
A sharp ammonia smell is not normal for the salt and can mean it has met an alkali such as sodium hydroxide. Do not open, handle or attempt to close a suspect container. Leave it undisturbed and report the suspected ammonia release for specialist assessment.
Is pathology waste coded differently?
A human healthcare setting may use 18 01 06* instead of 16 05 06*. Say whether the stock sits in a hospital pathology lab or a school or university when you ask for collection.
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