Frequently Asked Questions
What is ultrasonic cleaning – key questions answered clearly.
What is ultrasonic cleaning?
Ultrasonic cleaning is a highly effective cleaning process in which sound waves create tiny water vapor bubbles in a cleaning fluid; these implode and thereby remove dirt, blood and wound fluid even from the finest cavities. It is frequently used in the medical and dental sector and is the step before sterilization.
How does an ultrasonic cleaner work?
The ultrasonic cleaner uses sound waves to create negative pressure in the fluid, generating tens of thousands of tiny water vapor bubbles. These grow, become unstable and implode - the resulting micro-currents clean the surfaces down to the pores. This effect is called cavitation.
What is cavitation?
Cavitation refers to the formation and sudden implosion of tiny vapor bubbles in the cleaning fluid. Because tens of thousands of these implosions occur simultaneously, a strong cleaning effect is produced that reaches even hard-to-access areas.
What is the purpose of ultrasonic cleaning in instrument reprocessing?
It serves the thorough pre-cleaning and disinfection of instruments before they are sterilized in the autoclave. Without thorough pre-cleaning, safe sterilization is not possible - clean is the first step to sterile.
Does an ultrasonic cleaner replace the autoclave?
No. The ultrasonic cleaner complements the autoclave during pre-cleaning and disinfection, but does not replace it. As soon as instruments come into contact with blood or mucous membrane (critical instruments), a Class B autoclave is subsequently required.
Is an ultrasonic cleaner, UV or hot-air device enough, or do I need an autoclave?
For critical instruments a Class B autoclave is required; ultrasonic, UV and hot-air devices are not sufficient for this. The ultrasonic cleaner complements the autoclave during pre-cleaning, but does not replace it. Hot-air sterilizers have no longer been approved for critical instruments since 2021.
Does the ultrasonic bath belong to disinfection or to sterilization?
The ultrasonic bath belongs to the reprocessing step of cleaning and disinfection (chemical disinfection with disinfectant solution and water), not to sterilization. Critical instruments must subsequently be dried, packaged and sterilized.
How do I use an ultrasonic cleaner correctly?
Fill the unit with demineralized water and ultrasonic fluid up to the fill line, degas the bath and bring it up to temperature. Place the instruments in a basket (not directly on the bottom), start the cleaning cycle and then rinse the parts with warm water.
What do I fill the ultrasonic cleaner with?
Distilled or demineralized water plus about 1% of a suitable cleaning concentrate (so with 2 liters of water, around 20 ml). Other cleaning agents certified for medical instruments are also suitable.
Which cleaning or disinfection fluid is suitable for the ultrasonic cleaner?
For Steri24 ultrasonic cleaners, the fluid Multisteril CD is suitable, for example. The dosage averages around 2%; for the exact specifications, refer to the instructions for use of the respective agent.
What is the correct dosage of the cleaning fluid?
The dosage should average about 2%, but it can vary depending on the agent. Always observe the manufacturer's specifications in the instructions for use of the cleaning or disinfecting agent used.
How long and at what temperature do I clean parts in the ultrasonic cleaner?
Typically about 5 minutes at around 60 degrees C; this often shortens the required contact time of the disinfectant. The optimal temperature can be set on the unit. The entire cleaning cycle takes about 20 minutes.
What does degassing mean and why is it necessary?
Degassing removes dissolved air from the fresh cleaning fluid so that cavitation, and thus the cleaning effect, can fully take effect. Before placing instruments in, you should degas the bath and bring it up to temperature.
How do I degas the ultrasonic cleaner without a degassing function?
Simply switch on the ultrasonic cleaner with the ultrasonic function for 10 to 30 minutes - this achieves the same effect. The duration depends on the size: at about 10 liters around 10 minutes, at about 27 liters around 30 minutes. The process also speeds up the heating at the same time.
What is the difference between direct and indirect cleaning?
With direct cleaning you place the objects directly into the cleaning bath; the fluid should be changed after each cycle. With indirect cleaning you use a glass beaker in a fine-mesh basket, so that loose dirt does not remain in the unit and several materials can be cleaned at the same time.
Do I have to rinse instruments after ultrasonic cleaning?
Yes, rinse the objects with warm water after cleaning. This prevents cleaning fluid from penetrating or adhering.
Why should I not place the instruments directly on the bottom of the unit?
On the bottom of the unit the cavitation effect is uneven and the instruments can be damaged. Therefore always use the supplied basket; for small parts there are additionally fine-mesh baskets in round and rectangular versions.
What are frequencies in ultrasonic cleaning?
The frequency describes the number of vibrations per second and is given in hertz (Hz) or kilohertz (kHz). For ultrasonic cleaning, the frequencies usually range between 20 kHz and 50 kHz.
Which frequency is best for instrument cleaning?
20 kHz produces larger bubbles for fast, powerful cleaning, while 40 kHz produces small bubbles for intensive cleaning - ideal for hollow bodies and fine structures. Our ultrasonic cleaners operate at 40 kHz for a particularly thorough result.
At what frequency do the ultrasonic cleaners from Steri24 operate?
Our ultrasonic cleaners have a high cleaning frequency of 40 kHz. This creates fine bubbles that thoroughly clean even cavities and hard-to-reach areas.
What are the most important advantages of ultrasonic cleaning?
The three main advantages are: a thoroughly clean, pore-deep result even in hard-to-reach areas, gentle cleaning without scratches or damage, and a significant saving of time and effort, since the unit works automatically.
Does ultrasound clean more thoroughly than hand washing?
Yes, ultrasonic cleaning delivers a more thorough result than hand washing because it removes dirt down to the pores and from the finest cavities. By hand, this intensity cannot be achieved without damaging the instruments.
Does ultrasonic cleaning damage delicate instruments?
No, ultrasonic cleaning is not abrasive and does not attack the objects. Even delicate and intricately shaped parts can be cleaned gently.
Which instruments can I clean in the ultrasonic cleaner?
Most medical, dental and cosmetic instruments are suitable, especially those with fine structures, cavities or hard-to-reach areas. For delicate or coated parts, always observe the approvals of the instrument manufacturer.
Can I clean my hearing aids in the ultrasonic cleaner?
Only if the manufacturer of the hearing aid expressly permits or approves ultrasonic cleaning. When in doubt, refrain from it to avoid damage to the electronics.
Can I also clean electronics or technical parts in the ultrasonic cleaner?
Ultrasonic cleaners are suitable not only for medical purposes but also for electronics and technology. However, make sure that the respective parts have been approved by the manufacturer for ultrasonic cleaning.
What are the additional fine-mesh baskets for?
The additional baskets with extra-fine mesh are ideal for small parts and instruments that would otherwise fall through the standard basket. They are available in round and rectangular versions - consider the space required in the tank when choosing.
How much cleaning fluid goes into the tank?
Make sure the ultrasonic bath is filled with cleaning fluid up to the fill line or at least two thirds full. This ensures even cavitation and thus reliable cleaning.
How often do I have to change the cleaning fluid?
With direct cleaning you should replace the fluid after each cleaning cycle to avoid re-contamination. In addition, observe the change frequency specified by the manufacturer of the cleaning agent used.
What sizes of ultrasonic cleaners does Steri24 offer?
We carry ultrasonic cleaners from about 3 to 22 liters, suited to different instrument types and cleaning volumes. We are happy to advise you on which size is ideal for your needs.
Which ultrasonic cleaner is right for me?
That depends on the instrument type and the quantity. We advise you individually - from 3 to 22 liters, medically compliant - and help you find the right device. Feel free to use our consultation for this.
Do you offer ultrasonic cleaners and which of them are medical devices?
Yes, we carry ultrasonic cleaners. The higher-quality professional units are certified as medical devices; the more affordable models are not medical devices, but are suitable for manual instrument reprocessing. A small ultrasonic cleaner is also suitable for the gentle cleaning of delicate products.
Which devices are medical devices and which are not?
Autoclaves and our higher-quality ultrasonic cleaners are medical devices. Sealing devices fall under the Machinery Directive and bear only the CE mark. For reprocessing critical A instruments, an ultrasonic cleaner declared as a medical device is not strictly required.
Do I strictly need an ultrasonic cleaner declared as a medical device for critical A instruments?
No, for reprocessing critical A instruments an ultrasonic cleaner declared as a medical device is not strictly required. For critical B instruments, on the other hand, a washer-disinfector / thermal disinfector is required. We are happy to advise you on the right choice of device.
Is ultrasonic cleaning required under RKI/KRINKO?
Instruments must be cleaned before sterilization and disinfected depending on their classification, but according to RKI an ultrasonic cleaner is not strictly required for this. For critical instruments, however, a standardized, reproducible cleaning with proven efficacy is required, for which machine-based processes are well suited.
Why is cleaning the most important step before sterilization?
Sterilization can only work reliably if the instruments have been thoroughly cleaned beforehand - dirt residues can impair sterilization. According to KRINKO, effective cleaning is a prerequisite for safe reprocessing.
What happens if instruments are not thoroughly cleaned before sterilization?
Remaining residues such as blood or tissue can impair the sterilization effect and burden the instruments or the autoclave. Thorough pre-cleaning, e.g. in an ultrasonic bath, is therefore indispensable.
What does the entire reprocessing workflow look like?
Reprocessing takes place in several steps: pre-cleaning/cleaning (e.g. ultrasonic bath or thermal disinfector), disinfection, drying and packaging, followed by steam sterilization in the autoclave. The exact requirements depend on RKI/KRINKO and the instrument manufacturers' specifications.
Is manual pre-cleaning necessary before the ultrasonic bath?
A manual pre-cleaning of coarse dirt under running water or with a plastic brush is advisable so that the ultrasonic bath does not become contaminated too quickly. Use plastic rather than metal brushes for brushing, so as not to damage the instruments.
Can I use distilled water in the ultrasonic cleaner?
Yes, distilled or demineralized water is the right base for the cleaning bath, supplemented with the appropriate cleaning concentrate. It avoids limescale deposits and supports an even cleaning effect.
Is sterilization paper suitable for ultrasonic cleaning?
No, sterilization paper is used to wrap the instruments before sterilization so that they remain sterile. It is not suitable for ultrasonic cleaning, as it would soften in the bath.
How do I clean endoscopes or fine hollow-body instruments?
Such instruments benefit from a frequency that produces fine bubbles (e.g. 40 kHz), which also reach into cavities. In addition, observe the cleaning and disinfection recommendations of the respective instrument manufacturer.
How do I correctly clean PA or periodontal probes?
PA / periodontal probes are critical A instruments: clean and disinfect in the washer-disinfector or ultrasonic cleaner, then sterilize packaged in the autoclave and store packaged. Several instruments may lie in one package.
Do you offer sets with an autoclave and ultrasonic cleaner?
Yes, you can put together your shopping cart individually (e.g. an autoclave plus an ultrasonic cleaner and additional accessories) or we can create an individual package offer. Our value bundles combine an autoclave and matching accessories at a reduced price.
How do the professional units differ from the more affordable ultrasonic cleaners?
The higher-quality professional units are certified as medical devices and designed for medically compliant reprocessing, while the more affordable models are not medical devices but are suitable for manual instrument reprocessing or the gentle cleaning of delicate products. We are happy to advise you on which model suits your application.
What does an ultrasonic cleaner cost at Steri24?
The price depends on the size and equipment of the device. Steri24 stands for very good prices combined with high-quality service - you can see the current prices on the respective product pages or get advice.
How does Steri24 differ from established expensive providers?
As a family business since 1957, Steri24 offers medically compliant devices at fair prices - with a large, fast on-site service network in DACH (39 locations and 150 partners). This gives you comparable performance and service quality without paying the high prices of some established manufacturers.
Does Steri24 offer service and advice for ultrasonic cleaners?
Yes, our specialists are happy to advise you on device selection, application and care - by phone or e-mail. In addition, you benefit from our on-site service network in Germany, Austria and Switzerland.
My ultrasonic cleaner does not clean thoroughly - what could be the cause?
Common causes are an undegassed bath, too little fluid (below two thirds), incorrect dosage of the cleaning agent, a solution that is too cold, or instruments lying directly on the bottom instead of in the basket. Check these points; if problems persist, our service team will help you further.
How do I find the right ultrasonic cleaner or autoclave for my practice?
Use our autoclave configurator or get advice from our specialists - we recommend devices based on instrument type, quantity and risk class. This way we ensure that pre-cleaning and sterilization are optimally matched.
.png "Preview: Clavio DokuSoft")
