Interacoustics AT235 User manual

Instructions for Use - EN
AT235
Science made smarter
D-0133834-A – 2022/09

Table of Contents
1INTRODUCTION....................................................................................................................................... 1
1.1 About this manual .............................................................................................................................. 1
1.2 Intended use ...................................................................................................................................... 1
1.3 Contraindications for performing impedance audiometry.................................................................. 1
1.4 Product description ............................................................................................................................ 2
1.5 About warnings and cautions............................................................................................................. 3
2UNPACKING AND INSTALLATION ........................................................................................................ 4
2.1 Unpacking and inspection.................................................................................................................. 4
2.2 Markings ............................................................................................................................................ 5
2.3 Important safety instructions.............................................................................................................. 6
2.4 Malfunction......................................................................................................................................... 7
2.5 Connections....................................................................................................................................... 8
2.6 Calibration cavities............................................................................................................................. 8
2.7 Changing probe system..................................................................................................................... 9
2.8 Safety precautions to take when connecting the AT235. ................................................................ 10
2.9 Security precautions ........................................................................................................................ 10
2.10 License............................................................................................................................................. 11
2.11 About Diagnostic Suite .................................................................................................................... 12
3OPERATING INSTRUCTIONS............................................................................................................... 13
3.1 Handling and selection of ear tips ................................................................................................... 14
3.2 Switching the AT235 on and off....................................................................................................... 14
3.3 Probe status..................................................................................................................................... 15
3.4 Use of standard and clinical probe system...................................................................................... 16
3.5 AT235 stand-alone operation .......................................................................................................... 16
3.5.1 AT235 stand-alone operation panel........................................................................................... 16
3.5.2 Startup........................................................................................................................................ 17
3.5.3 Instrument settings – language, printer, date & time, etc. ......................................................... 18
3.5.4 Test and module selection ......................................................................................................... 19
3.5.5 Tympanometry test screens....................................................................................................... 19
3.5.6 Audiometry test screen .............................................................................................................. 24
3.5.7 Start and stop of a tympanometric test ...................................................................................... 25
3.5.8 Save ........................................................................................................................................... 26
3.5.9 View historical sessions ............................................................................................................. 27
3.6 Operating in sync mode (only with Diagnostic Suite) ...................................................................... 28
3.6.1 PC power configuration.............................................................................................................. 28
3.6.2 Starting from OtoAccess® ......................................................................................................... 28
3.6.3 Starting from Noah 4.................................................................................................................. 28
3.6.4 Crash report ............................................................................................................................... 28
3.6.5 Instrument setup ........................................................................................................................ 29
3.7 Using sync mode ............................................................................................................................. 30
3.7.1 Using IMP sync .......................................................................................................................... 30
3.7.2 Using AUD sync......................................................................................................................... 32
3.7.3 SYNC mode ............................................................................................................................... 34
3.7.4 Client upload .............................................................................................................................. 35
3.7.5 Session download...................................................................................................................... 35

4MAINTENANCE ...................................................................................................................................... 37
4.1 General maintenance procedures ................................................................................................... 37
4.2 General maintenance procedures ................................................................................................... 40
4.3 Cleaning the probe tip...................................................................................................................... 41
4.4 Concerning repair ............................................................................................................................ 42
4.5 Warranty .......................................................................................................................................... 42
4.6 Periodic calibration .......................................................................................................................... 43
5TECHNICAL SPECIFICATIONS ............................................................................................................ 44
5.1 AT235 Technical specifications ....................................................................................................... 44
5.2 Calibration properties....................................................................................................................... 46
5.3 Reference equivalent threshold values for transducers .................................................................. 50
5.4 Pin assignments .............................................................................................................................. 51
5.5 Electromagnetic compatibility (EMC)............................................................................................... 52

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1Introduction
1.1 About this manual
This manual is valid for the AT235 firmware version 1.42.
The product is manufactured by:
Interacoustics A/S
Audiometer Allé 1
5500 Middelfart
Denmark
Tel.: [phone]
Fax: [phone]
E-mail: [e-mail]
Web: www.interacoustics.com
1.2 Intended use
The AT235 is an automatic impedance audiometer with built-in screening audiometry suited for screening, as
well as diagnostic work. Neonatal screening programs will particularly appreciate the presence of high probe
tone tympanometry, allowing more dependable tympanometric results in neonates.
The AT235 tympanometer is intended to be used by an audiologist, hearing healthcare professional, or
trained technician in a quiet environment.
1.3 Contraindications for performing impedance audiometry
•Recent stapedectomy or another middle ear surgery
•Discharging ear
•Acute external auditory canal trauma
•Discomfort (e.g., severe otitis externa)
•Occlusion of the external auditory canal
•Presence of tinnitus, hyperacusis or other sensitivity to loud sounds may contraindicate testing when
high intensity stimuli are used
Testing should not be performed on patients with such symptoms without a medical doctor’s approval.
Visual inspection for obvious structural abnormalities of the external ear structure and positioning as well as
the external ear canal should be performed before testing.

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1.4 Product description
The AT235 consist of the following parts:
Included Parts
AT235 instrument.
Clinical Probe System1.
Diagnostic Probe System1, 2.
Power supply unit UES65-240250SPA3.
Contralateral headphone1.
Daily check cavity.
CAT50 (option).
DD65v2 Audiometric headset.
Patient Response (Option).
Printer kit (Option).
Wall mounting kit (Option).
Cleaning cloth.
Assortment bag BET55.
1Applied part as according to IEC60601-1
2 One can be selected.

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1.5 About warnings and cautions
Throughout this manual the following meaning of warnings, cautions and notices are used:
WARNING indicates a hazardous situation which, if not avoided, could result in
death or severe injury.
CAUTION, used with the safety alert symbol, indicates a hazardous situation
which, if not avoided, could result in minor or moderate injury.
NOTICE
NOTICE is used to address practices not related to personal injury.

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2Unpacking and installation
2.1 Unpacking and inspection
Check box and contents for damage
When the instrument is received, please check the shipping box for rough handling and damage. If the box is
damaged, it should be kept until the contents of the shipment have been checked mechanically and
electrically. If the instrument is faulty, please contact your local distributor. Keep the shipping material for the
carrier’s inspection and insurance claim.
Keep carton for future shipment
AT235 comes in its own shipping carton, which is specially designed for the AT235. Please keep this carton.
It will be needed if the instrument must be returned for service.
If service is required, please contact your local distributor.
Reporting imperfections
Inspect before connection
Prior to connecting the product it should once more be inspected for damage. All the cabinet and the
accessories should be checked visually for scratches and missing parts.
Report immediately any faults
Any missing part or malfunction should be reported immediately to the supplier of the instrument together
with the invoice, serial number, and a detailed report of the problem. In the back of this manual, you will find
a "Return Report" where you can describe the problem.
Please use the "Return Report"
Use of the return report provides the service engineer with the relevant information to investigate the
reported issue. Without this information, there may be difficulty in determining the fault and repairing the
device. Please always return the device with a completed Return Report to guarantee that correction of the
problem will be to your satisfaction.
Use only specified power supply unit UES65-240250SPA3 type.

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2.2 Markings
The following markings can be found on the instrument:
Symbol
Explanation
Type B applied parts.
Patient applied parts that are not conductive and can be immediately
released from the patient.
Refer to instruction manual
WEEE (EU-directive)
This symbol indicates that when the end-user wishes to discard this product,
it must be sent to separate collection facilities for recovery and recycling.
0123
The CE-mark in combination with MD symbol indicates that Interacoustics
A/S meets the requirements of the Medical Device Regulation (EU)
2017/745. Approval of the quality system is made by TÜV – identification no.
0123.
Medical Device
Year of manufacture
Do not re-use Parts like ear-tips and similar are for single use only
Display Port Connection – HDMI type
“ON” / “OFF” (push-push)

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2.3 Important safety instructions
Read this instruction manual carefully and completely before using the product.
1. External equipment intended for connection to signal input, signal output or other connectors shall
comply with relevant IEC standard (e.g., IEC 60950 for IT equipment). In these situations, an optical
isolator is recommended to fulfill the requirements. Equipment not complying with IEC 60601-1 shall
be kept outside the patient environment, as defined in the standard (usually 1.5 meter). If in doubt,
contact qualified medical technician or your local representative.
2. This instrument does not incorporate any separation devices at connections for PC’s, printers, active
speakers etc. (Medical Electrical System). A galvanic l isolator is recommended to fulfill the
requirements. For safe setup please refer to section 2.3.
3. When the instrument is connected to a PC and other items of equipment of a medical electrical system
assure that the total leakage current cannot exceed the safety limits and that separations have the
dielectric strength, creepage clearances and air clearances required fulfilling the requirements of
IEC/ES 60601-1. When the instrument is connected to a PC and other similar items be aware of not
touching the PC and patient simultaneously.
4. To avoid the risk of electric shock, this equipment must only be connected to supply mains with
protective earth.
5. Do not use any additional multiple socket-outlet or extension cord. For safe setup please refer to
section 2.3
6. This instrument contains a coin-type lithium battery. The cell can only be changed by service
personnel. Batteries may explode or cause burns, if disassembled, crushed, or exposed to fire or high
temperatures. Do not short-circuit.
7. No modification of this equipment is allowed without Interacoustics authorization.
Interacoustics will make available on request circuit diagrams, component part lists, descriptions,
calibration instructions, or other information that will assist service personnel to repair those parts of
this audiometer that are designated by the Interacoustics as repairable by service personnel.
8. For maximum electrical safety, turn off the power from a mains powered instrument when it is left
unused.
9. The instrument is not protected against harmful ingress of water or other liquids. If any spillage occurs
check the instrument carefully before use or return for service.
10. No part of the equipment can be services or maintained while in use with the patient.
1. Never insert or in any way use the insert headset without a new clean non defect test tip. Always
make sure that foam or ear-tip is mounted correctly. Ear tips and foam are single use.
2. The instrument is not intended to be used in environments exposed to fluid spills.
3. The instrument is not intended to be used in oxygen rich environments or use in conjunction with
flammable agents.
4. Check calibration if any parts of the equipment is exposed to shock or rough handling.

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NOTICE
1. To prevent system faults, take appropriate precautions to avoid PC viruses and similar.
2. Use only transducers calibrated with actual instrument. To identify a valid calibration, the serial
number for the instrument will be marked on the transducer.
3. Although the instrument fulfils the relevant EMC requirements precautions should be taken to avoid
unnecessary exposure to electromagnetic fields, e.g., from mobile phones etc. If the device is used
adjacent to other equipment it must be observed that no mutual disturbance appears. Please also
refer to EMC considerations in section 5.4
4. Use of accessories, transducers, and cables other than specified, except for transducers and cables
sold by Interacoustics or representatives may result in increased emission or decreased immunity of
the equipment. For list of accessories, transducers and cables that fulfils the requirements please refer
to section 5.4
5. Within the European Union it is illegal to dispose electric and electronic waste as unsorted municipal
waste. Electric and electronic waste may contain hazardous substances and therefore
must be collected separately. Such products will be marked with the crossed-out
wheeled bin shown below. The cooperation of the user is important to ensure a high
level of reuse and recycling of electric and electronic waste. Failing to recycle such
waste products in an appropriate way may endanger the environment and consequently
the health of human beings.
6. Outside the European Union, local regulations should be followed when disposing of the product after
its useful life.
2.4 Malfunction
In the event of a product malfunction, it is important to protect patients, users, and other
persons against harm. Therefore, if the product has caused, or potentially could cause such
harm, it must be quarantined immediately.
Both harmful and harmless malfunctions, related to the product itself or to its use, must
immediately be reported to the distributor where the product was acquired. Please remember to
include as many details as possible e.g., the type of harm, serial number of the product,
software version, connected accessories and any other relevant information.
In case of death or serious incident in relation to the use of the device, the incident must
immediately be reported to Interacoustics and the local national competent authority.

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2.5 Connections
1
Probe
Dedicated probe connection.
2
LAN
LAN (Not used).
3
USB B
For printer, mouse, keyboard, Memory stick .
4
USB A
For PC connection.
5
HDMI
For external monitor or projector.
6
In 24 V
Use only specified power supply unit UES65-240250SPA3
type.
7
Trigger in / out
Cochlear implant trigger option.
8
Pat. Resp.
Patient response button.
9
Right
Audiometry Right output.
10
Left
Audiometry Left output.
11
Contra
Contra transducer output.
2.6 Calibration cavities
You can use the 0.2 ml, 0.5 ml, 2.0ml and 5 ml for validity check of the probe calibration.
To perform a calibration check, select a protocol the measures a tympanogram.
Do not use an ear tip! Place the probe tip completely into the cavity. Perform the measurement. Check the
volume that was measured.
The allowed tolerance in the volume measurement is ±0.1 ml for cavities up to 2 ml and ±5% for larger
cavities. These tolerances are applicable for all probe tone frequencies.
We strongly recommend calibrating probe and contra phone at least once a year.

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2.7 Changing probe system
Change between the standard and clinical probe as follows:
1. Locate the probe connection on the back of the unit.
2. Open the 2 locks by pushing them to the sides.
3. Swap to the other probe system.
4. Close the 2 locks by pushing them to the center.

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2.8 Safety precautions to take when connecting the AT235.
NOTICE
Please note that if connections are made to standard equipment like printers and networks, special
precautions must be taken to maintain medical safety.
2.9 Security precautions
NOTICE: As a part of data protection, ensure to be compliant to all the following points:
1. Use Microsoft supported operating systems
2. Ensure operating systems are security patched
3. Enable database encryption
4. Use individual user accounts and passwords
5. Secure psychical and network access to computers with local data storage
6. Use updated antivirus and firewall and anti-malware software
7. Implement appropriate backup policy
8. Implement appropriate log retention policy
Please follow instructions below.
Fig 1. AT235 used with the medically approved power supply UES65-240250SPA3.
Mains outlet
Medical power supply
AT235 alone

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Fig. 2. AT235 used with, a medically approved safety transformer and a wired connection to a PC.
Fig. 3. AT235 used with the
medically approved power
supply
The separable mains plug is used to safely disconnect mains from the device. Do
not position the power supply in a position so that it is difficult to disconnect the
device.
2.10 License
When you receive the AT 235 it already contains the license you have ordered. If you would like to add
licenses that are available in AT235, please contact your dealer for a license.
AT235
Medical power supply
Mains outlet
Medically approved
safety transformer
PC power supply
PC
Printer
Mains outlet
Medical power supply
AT235 alone
MPT-III printer
Fully charged,
WITHOUT POWER SUPPLY
CONNECTED
UES65-240250SPA3 and printout with HM-E300/MPT-III printer.
HM-E300

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2.11 About Diagnostic Suite
Should you go to Menu > Help > About then you will see the below window. This is the area of the software
where you can manage license keys and check your Suite, Firmware and Build Versions.
Also, in this window you will find the Checksum section which is a feature designed to help you identify the
integrity of the software. It works by checking the file and folder content of your software version. This is
using a SHA-256 algorithm.
On opening the checksum, you will see a string of characters and numbers, you can copy this by double
clicking on it.

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3Operating instructions
The instrument is switched on by pressing the ON button on the unit. When operating the instrument, please
observe the following general precautions:
1. Use this device only as described in this manual.
2. Use only the disposable Sanibel ear tips designed for use with this instrument.
3. Always use a new ear tip for each patient to avoid cross-contamination. The ear tip is not designed for
reuse.
4. Never insert the probe tip into the ear canal without affixing an ear tip as omission may damage the
patient’s ear canal.
5. Keep the box of ear tips outside the reach of the patient.
6. Be sure to insert the probe tip in a way which will assure an airtight fit without causing any harm to the
patient. Use of a correct and clean ear tip is mandatory.
7. Be sure to use only stimulation intensities acceptable to the patient.
8. When presenting contralateral stimuli using the insert phones – do not insert the phones or in any way
try to conduct measurements, without a correct insert ear tip in place.
9. Clean the headphone cushion regularly using a recognized disinfectant.
10. Contraindications to testing include recent stapedectomy or middle ear surgery, a discharging ear,
acute external auditory canal trauma, discomfort (e.g., severe otitis externa) or occlusion of the
external auditory canal. Testing should not be performed on patients with such symptoms without a
medical doctor’s approval.
11. The presence of tinnitus, hyperacusis or other sensitivity to loud sounds may contraindicate testing
when high intensity stimuli are used.
NOTICE
1. Careful handling of the instrument whenever in contact with a patient should be given high priority.
Calm and stable positioning while testing is preferred for optimal accuracy.
2. The AT235 should be operated in a quiet environment, so that measurements are not influenced by
outside acoustic noises. This may be determined by an appropriately skilled person trained in
acoustics. ISO 8253 Section 11, defines a quiet room for audiometric hearing testing in its guideline.
3. It is recommended that the instrument be operated within an ambient temperature range of 15°C /
59°F – 35°C / 95°F.
4. The headphone and insert phone are calibrated to the AT235 – introducing transducers from other
equipment requires a re-calibration.
5. Never clean the transducer housing with water or insert non-specified instruments into the transducer.
6. Do not drop and avoid other undue impact to this device. If the instrument is dropped or otherwise
damaged, return it to the manufacturer for repair and/or calibration. Do not use the instrument if any
damage is suspected.
7. Although the instrument fulfils the relevant EMC requirements, precautions should be taken to avoid
unnecessary exposure to electromagnetic fields, e.g., from mobile phones etc. If the device is used
adjacent to other equipment, caution must be taken to observe that no mutual disturbance appears.

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3.1 Handling and selection of ear tips
When using the AT235 probe and CIR contra phone, Sanibel ear tips must be used.
The Sanibel ear tips are single use only and should not be reused. Reuse of ear tips can lead to the spread
of infection from patient to patient.
The probe and CIR contra phone must be fitted with an ear tip of a suitable type and size before testing.
Your choice will depend on the size and shape of the ear canal and ear. Your choice may also depend on
personal preference and the way you perform your test.
When performing a quick impedance screening test, you may choose an umbrella shaped ear
tip. Umbrella ear tips seal the ear canal without the probe tip going into the ear canal. Press
the ear tip firmly into the ear canal in such a way that a seal remains during the complete test.
For more stable testing, we recommend using an extension cord with a mushroom shaped
ear tip. Make sure that this ear tip inserts completely into the ear canal. Mushroom shaped
ear tips allow you to test ‘hands free’ from the AT235. This reduces the chance of contact
noise disturbing the measurement.
Refer to the “Selecting the Correct Ear Tip” Quick Guide included in the AT235 Additional Information
document for an overview of ear tip sizes and selection.
3.2 Switching the AT235 on and off
Switch the AT235 on or off by pressing the ON (1).
NOTICE
The AT235 takes approximately 35 seconds to boot up. Allow the unit to warm up for 1 minute before use.

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3.3 Probe status
The probe status is indicated by the color of the light on the control panel, standard probe system and the
clinical probe system. Below, the colors and their meanings are explained:
Color
Control panel
Standard probe
Clinical probe
Status
Red
Right ear is selected. Probe is out of
the ear.
Blue
Left ear is selected. Probe is out of
the ear.
Green
Probe is in the ear and a seal is
maintained.
Yellow
Probe is in the ear and is blocked,
leaking or too noisy.
White
The probe has just been attached.
Probe status is unknown. If the probe
light stays white in any other situation
the AT235 may need to be switched
off and back on again to regain
proper probe status.
Blinking
AT235 is pausing and/or an
interaction is expected. The AT235
will for example remain blinking green
if the protocol has finished testing and
the probe is still in the ear. The user
may pause the AT235 before
inserting the probe resulting in blue or
red blinking.
No light
AT235 is not monitoring the probe
status.

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3.4 Use of standard and clinical probe system
For establishing most stable measurements, it is recommended not to hold the probe between fingers during
the measurements. Particularly acoustic reflex measurements could be affected by probe movements.
3.5 AT235 stand-alone operation
3.5.1 AT235 stand-alone operation panel
Name
Description
1
ON
Turns the AT235 ON and OFF.
2
Shift
Shift is used to access secondary functions of the other keys.
3
Setup
Hold down Setup and use the wheel (19) to select the desired
Setup menu then let go of the Setup button to open it.
4-13
Function keys
The 10 function keys hold functions of which labels are displayed
in the screen.
14
Tests
Hold down Test and use the wheel (19) to select the desired
protocol or audiometry or impedance module. Let go of the Test
button to make your selection.
15
New Session
Clears data and starts a new session in the current module.
16
Clients
Press the Clients button to open a window in which a client can
be selected, edited, or created. Also, its historic sessions can be
viewed.
17
Save
Saves the current session for the current module.
18
Print
Prints the session that is currently on screen.
19
Wheel
Used for manual pump control as well as scrolling through menus
and selection possibilities. In the audiometry module the wheel
controls the stimulus intensity.
20
Tymp
Selects or deselects a tympanogram test from the protocol.

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21
Reflex
Selects or deselects a reflex test from the protocol. If necessary,
a test with ipsilateral or contralateral reflexes is automatically
added to the protocol.
22
Tone Switch, Enter,
Start/stop
In audiometry it is the tone switch. In tympanometry it interrupts
or starts the auto-start function, and it operates as a stop and
start button while the probe is in an ear. In menus that require
textual input the tone switch is used for making selections.
23
Right
Selects right ear for testing.
24
Left
Selects left ear for testing.
3.5.2 Startup
The AT235 will always load the last used tympanometry protocol as a starting point.