B.Ed Special Education HI Paper C1 Notes: Audiological Assessment

If you are studying B.Ed Special Education (Hearing Impairment), one of the most important and technical subjects you will face is Paper C1: Identification of Disability and Assessment of Needs.

As a future Special Educator, you are not a doctor, but you must know how to read a child’s medical reports. When a deaf child joins your classroom, the first document the parents will show you is an Audiogram.

In these notes, we will explain the basics of Audiological Assessment, how an Audiometer works, and how you can easily read an Audiogram. We have kept the language simple (Simple Indian English) so you can easily write this in your RCI exams.

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1. What is Audiological Assessment?

Audiological assessment is the scientific process of testing a person’s hearing ability. It tells us two main things:

1. Degree of Hearing Loss: How much hearing is lost? (Mild, Moderate, Severe, or Profound).
2. Type of Hearing Loss: Where is the problem? (Outer ear, Middle ear, or Inner ear).

There are two types of hearing tests:

• Subjective Tests: The patient has to respond (e.g., raising a hand when they hear a beep). Example: Pure Tone Audiometry (PTA).
• Objective Tests: The machine calculates the hearing automatically without the patient doing anything. Example: BERA, OAE (usually done for newborn babies).

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2. The Audiometer: The Testing Machine

An Audiometer is an electronic machine used by an Audiologist to measure hearing loss.

How does it work?

• It produces sounds at different Frequencies (Pitch) and different Intensities (Loudness).
• The patient sits in a soundproof room and wears headphones.
• When the patient hears a sound, they press a button.
• The machine records the softest sound the patient can hear. This softest sound is called the “Threshold.”

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3. Understanding Sound: Frequency and Intensity

To read an audiogram, you first need to understand the two parameters of sound:

• Frequency (Pitch): This is how high or low a sound is. It is measured in Hertz (Hz).
  • A bird chirping is a high-frequency sound.
  • A drum beating is a low-frequency sound.
• Intensity (Loudness): This is the volume of the sound. It is measured in Decibels (dB).
  • Normal breathing is about 10 dB.
  • A normal conversation is about 50-60 dB.
  • An aeroplane engine is about 120 dB.

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4. What is an Audiogram?

An Audiogram is a graph that shows the results of the Pure Tone Audiometry (PTA) test. It is a visual picture of a person’s hearing threshold.

How to Read the Audiogram Graph:

Imagine a graph with an X-axis (horizontal line) and a Y-axis (vertical line).

• The Top Line (X-axis) shows Frequency (Pitch): It reads from left to right, usually starting at 125 Hz (low pitch) and going up to 8000 Hz (high pitch).
• The Side Line (Y-axis) shows Intensity (Loudness): It reads from top to bottom, starting from -10 dB (very soft) down to 120 dB (very loud).

The Symbols on the Audiogram (Very Important for Exams):

Audiologists use universal symbols to mark the hearing threshold on the graph:

• Right Ear: Marked with a red “O”.
• Left Ear: Marked with a blue “X”.
• Bone Conduction: Marked with < or >.

If you look at the graph and see blue ‘X’ marks at the 80 dB line, it means the child has a severe hearing loss in the left ear.

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5. Classification of Hearing Loss (WHO Guidelines)

When you look at the child’s Audiogram, check where the marks (X and O) fall on the dB scale. Then compare it with this chart:

Hearing Level (dB)	Degree of Hearing Loss	Educational Implication
0 to 25 dB	Normal Hearing	No problem in the classroom.
26 to 40 dB	Mild Hearing Loss	Misses soft speech; needs to sit in the front row.
41 to 60 dB	Moderate Hearing Loss	Needs a hearing aid to follow normal conversation.
61 to 80 dB	Severe Hearing Loss	Needs powerful hearing aids and speech therapy.
81 dB and above	Profound Hearing Loss	Relies heavily on Indian Sign Language (ISL) or Cochlear Implants.

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6. Aided vs. Unaided Audiograms

• Unaided Audiogram: This is the hearing test done without wearing a hearing aid. It shows the natural hearing loss.
• Aided Audiogram: This is the test done while the child is wearing their Hearing Aid or Cochlear Implant. The marks on this graph are usually shown by the letter “A”.
• Why is this important? As a special educator, the Aided Audiogram tells you if the child’s hearing aid is actually working and helping them in your class.

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7. Why Must a Special Educator Know This? (Conclusion)

You might wonder, “Why do I need to study audiology in a B.Ed course?”

If you do not know the child’s exact hearing loss, you cannot plan your teaching. For example, if an audiogram shows that a child has a “High-Frequency Hearing Loss,” it means they cannot hear sounds like /s/, /sh/, or /f/. If you dictate the word “Sun,” they might hear it as “Un.”

Understanding the audiogram helps you adapt your lesson plans, speak clearly, and use visual aids to support the child.

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Frequently Asked Questions (FAQs)

Q1: What do ‘X’ and ‘O’ mean on an Audiogram?

Ans: According to international standards, the ‘O’ symbol (usually in red) represents the right ear, and the ‘X’ symbol (usually in blue) represents the left ear in an air-conduction hearing test.

Q2: What is the normal hearing range for a human?

Ans: For children and adults, a hearing threshold between 0 dB to 25 dB across all frequencies is considered normal hearing.

Q3: Can an audiogram tell if a child needs a hearing aid?

Ans: Yes. If the audiogram shows a hearing threshold worse than 40 dB (Moderate loss or above), an Audiologist will usually recommend a hearing aid.