General guidelines

Definition of hazardous waste

As per § 3 of the Abfallverzeichnis-Verordnung (waste index regulation), waste displaying one or several of the following characteristics is deemed to be hazardous:

  • flammable
  • poisonous
  • harmful to health
  • corrosive
  • irritant
  • carcinogenic
  • teratogenic (harmful for reproduction)
  • mutagenic (likely to cause changes to the human genome)
  • hazardous to the environment
  • explosive
  • flammable/combustible
  • contagious

Chemical waste consists of unused chemicals in their original containers. We accept unused chemicals in their original containers if these are intact.

Avoiding the production of hazardous waste

Disposing of hazardous waste is expensive. You should therefore take care to produce as little hazardous waste as possible.

Every staff member is obliged to update the hazardous materials database (DaMaRIS) regulary. You can access the database from the University of Konstanz website.

The following guidelines apply:

  • Before you acquire new chemicals, please check whether the substance in question is already available to your working group or whether it is included in the DaMaRIS materials exchange.
  • Please call Dr Ursula Locher (+49 7531 88 -4292) if you require chemicals from the DaMaRIS materials exchange.
  • Do not hoard unnecessary amounts of chemicals.
  • You must enter new chemicals acquisitions or depletion into DaMaRIS as soon as they occur.
  • If possible, try to re-use solvents via distillation.
  • Try to avoid using chemicals that are difficult to dispose of (e.g. solvents containing halogens, mercury, arsenic and cadmium compounds, chromic sulfuric acid).
  • Chemicals that are no longer needed should be released for general use via the DaMaRIS exchange or disposed of at the “Sonderabfallannahme” (hazardous waste collection point).

For safety reasons, it is strictly prohibited to amass and store large quantities of hazardous waste in your laboratory. Waste designated for disposal should be delivered to the “Sonderabfallannahmestelle” as soon and as regularly as possible.

Abandoned chemicals

Abandoned chemicals pose a major problem. These are chemicals that have not been labelled properly or that no one feels responsible for, e.g. because the original owner has left the university.

These “leftovers” create various problems:

  • Handling unknown chemical substances poses a major risk to staff members.
  • When handing these substances over to the “Sonderabfallannahmestelle”, a person other than the original waste producer will sign the declaration form, assuming the original owner’s liability.
  • The University of Konstanz’s “Sonderabfallannahmestelle” does not accept unknown substances.
  • No disposal company will process or dispose of substances of unknown or uncertain composition.

Such "leftovers" can be avoided by consistently checking and updating the inventory.

Gas bottles + gas cartridges

Gas cylinders and gas cartridges are summarized under the term compressed gas containers.

Camping gas cartridges must be completely emptied (used up) and handed in at the acceptance times at the hazardous waste area.

Gas cylinders may only be transported with suitable aids and protective caps and must be secured against mechanical impact (falling over) when stationary.

Before working with gases, the gas cylinder should be leak-tested. Also ensure that the gas hoses, valves and pressure reducers are in perfect condition. The date of the next due inspection must be observed.

Gas cylinders purchased from the gas storage facility must be returned there before the TÜV deadline is exceeded, even if the contents have not been completely used up. Before placing an order with another supplier, it should be checked whether the supplier will take the cylinder back. In this case, the return must also be arranged in good time.

Gas cylinders with e.g. exceeded TÜV inspection period, which are not taken back by the gas storage facility, must be reported to the hazardous waste department. The hazardous waste department will arrange for special disposal.

The costs of a gas filling usually amount to a few hundred euros. In contrast, the disposal of a single pressurised gas cylinder without TÜV costs at least €6,000.

On 12.12.2017, the occupational safety committee decided that if the TÜV inspection deadlines are not met, the working groups will bear the disposal costs.

Safety advice

Please take note of the following when collecting hazardous waste:

  • Individual components must not react to one another.
  • Your waste must not produce any gases. The container must be ventilated or remain sealed within the fume cupboard until gas production ceases.
  • Waste prone to reacting violently or forming unstable products must be neutralised.
  • Waste liable to react violently with water or air, as well as highly corrosive, oxidising or reducing substances, must also be neutralised.

This includes, amongst other things, acid chlorides and acid anhydrides (e.g. acetic anhydride, thionyl chloride, phosphorus pentachloride, phosphorus oxychloride, chlorosulfonic acid), fuming sulfuric acid (oleum), phosphorus, alkali metals, alkali hydrides, calcium hydride, lithium aluminium hydride, alkaline borohydride, organic lithium compounds (e.g. butyllithium), organometallic and metal carbonyl compounds, dimethyl sulphate, diethyl sulphate, Raney nickel, cyanide, traces of bromine and iodine.

Liquid hazardous waste must be collected in approved containers only and must be correctly labelled.

The waste producer is responsible for packaging and fully declaring their hazardous waste!

Please note that waste producers remain responsible for their waste even after it has been handed over to the hazardous waste collection point and the disposal company!

They are fully responsible for any potential damage to human beings or the environment that is caused by improper collection, mixing or declaration of hazardous waste!


Hazardous waste must be collected in special containers. These can be obtained from the Chemistry inner courtyard during opening hours .

The following containers are available:

  • for liquid waste: 5 and 10-litre plastic containers
  • for solid waste: white plastic barrels with blue screw-on lids

Please contact our waste coordinator Mr Müller (+49 7531 88 -2747) if you want to use other containers or sizes (e.g. larger barrels for collecting used oils fit for recycling).

Whatever the container you’re using, it must not be filled beyond 90% capacity. They must be sealed shut and clean. Containers that are too full, damaged, leaky or contaminated will not be accepted by the “Sonderabfallsammelstelle” (hazardous waste collection point).

The plastic containers must not be older than 5 years starting from the manufacturing date. You will find the manufacturing date on the TÜV seal or the so-called “UN code”. Example: UN 3H1/X1.5/250/14/… This container was produced in 2014 and may be used until 2019.

Please check the manufacture date carefully since we cannot accept containers with expired UN codes.

Using glass bottles as storage containers for liquid waste is strictly prohibited due to risk of breakage.

Declaration (labelling)

Waste containers must be clearly labelled. Please go to our Documentation and labels website to print off the required labels.

If you’re using plastic barrels, please attach one label each on the side of the barrel and on the lid.

In the laboratory, solvent waste must be clearly labelled. We recommend that you tie laminated labels to the handle of the plastic canister. Research groups that do not have access to a laminator can get the appropriate labels from the "Sonderabfallsammelstelle" (hazardous materials collection point).


We only accept hazardous waste that is accompanied by the correct documentation. Acceptable exceptions are included in the list of waste products.

Please only use the most current form of the documents.

The document must include the following information:

  • departmental chair, working group or division and room number
  • quantity
  • if you are disposing of liquid waste, please specify what kind it is (e.g. halogen-free solvents, acids etc.)
  • the individual components
  • information on particularly poisonous (e.g. arsenic and mercury), highly flammable (e.g. ether) or other “highly dangerous” components (e.g. ethidium bromide), even if these only occur as traces.
  • information on dyes in aqueous solutions
  • pH-value of aqueous solutions, acids and bases
  • if you are disposing of contaminated equipment, please name the device and provide information on what kind of contamination has occurred
  • Properties of hazardous materials
  • Name (in capital letters), signature, phone number and date

By signing the document, the undersigned confirms that the information provided as well as the declaration in its entirety is correct.

They also confirm that the waste does not include pyrophoric substances or highly oxidising or reducing agents.

All entries must be clearly legible, in permanent ink and complete.

Any waste accumulated over the course of an internship must be signed for by the person responsible (superior/instructor or assistant). Student signatures do not qualify.