| 📋 Article Summary — Audiometric Testing in Australian Workplaces | |
|---|---|
| Key Fact 1 | Audiometric testing must be offered within 3 months of commencing noise work and every 2 years thereafter under the Safe Work Australia Noise Code |
| Key Fact 2 | A standard threshold shift (STS) of ≥10 dB average shift at 2, 3, and 4 kHz triggers mandatory investigation and re-evaluation of controls |
| Key Fact 3 | Workers must be away from significant noise for at least 14 hours before a baseline audiogram to avoid temporary threshold shift (TTS) contaminating results |
| Read Time | 9 min |
The Legal Requirement for Audiometric Testing
Under the Safe Work Australia Code of Practice for Noise, PCBUs must offer audiometric testing to workers who are frequently required to use hearing protection, or who are regularly exposed to noise above the action level (defined in most Australian jurisdictions as 85 dB(A) LAeq,8h). While hearing testing is offered rather than mandated for workers (who may refuse), the PCBU is legally required to make it available at no cost to the worker.
Testing schedule under the Code of Practice:
- Baseline audiogram: Within 3 months of commencing work in a noisy environment (ideally before commencing, to establish pre-exposure baseline)
- Periodic monitoring: Every 2 years for workers with ongoing significant noise exposure
- Annual testing: May be required where a worker’s baseline audiogram shows pre-existing hearing loss, or where exposure levels are very high
- Exit audiogram: When a worker leaves a position involving noise exposure (important for both the worker’s and the employer’s records)
AS/NZS 1269.4: The Australian Standard for Workplace Audiometric Testing
Audiometric testing in Australian workplaces must comply with AS/NZS 1269.4:2014. Key requirements include:
- Test environment: The audiometric test booth or room must meet maximum permissible ambient noise levels specified in AS/NZS 1269.4 at each test frequency. A test conducted in a noisy environment will artificially elevate thresholds (making hearing appear worse than it is).
- Instrumentation: Audiometers must be calibrated and meet IEC 60645 requirements. Audiometer calibration certificates must be current.
- Test frequencies: The standard requires testing at 500, 1000, 2000, 3000, 4000, 6000, and 8000 Hz for occupational audiometry.
- Operator qualifications: The person conducting the test must have appropriate training. Audiograms showing significant abnormalities should be reviewed by a registered audiologist or occupational physician.
- Pre-test requirements: Workers must have been away from significant noise exposure for at least 14 hours before the test to avoid temporary threshold shift. The test form should document time since last noise exposure.
Reading an Audiogram
An audiogram is a graph of hearing thresholds (in dB HL — hearing level) at each test frequency, separately for left and right ears. Normal hearing thresholds are 0–25 dB HL across all frequencies. The typical NIHL pattern is:
- Normal or near-normal thresholds at 500–2000 Hz
- Notch (dip) at 3000–6000 Hz, most pronounced at 4000 Hz
- Partial recovery at 8000 Hz
For occupational surveillance purposes, the key comparison is between the baseline audiogram and each subsequent periodic audiogram. Progressive worsening of the 4 kHz notch, or spreading of threshold shift to lower frequencies, indicates ongoing noise-induced damage.
Significant Threshold Shift: When to Act
A significant threshold shift (STS) — defined in most frameworks as an average worsening of ≥10 dB at 2, 3, and 4 kHz (or significant worsening at 4 kHz alone in some protocols) — triggers a mandatory response:
- Re-test the worker (to rule out temporary threshold shift, equipment error, or technique variability)
- Review noise exposure controls for the worker
- Refer the worker to an audiologist or occupational physician for further assessment
- Review the overall noise control program for the area where the worker is employed
- Document findings and actions taken
Where a worker has an STS confirmed on re-testing, this may also represent a recordable hearing loss for workers’ compensation and WHS injury recording purposes. Legal advice should be sought where there is doubt about notification obligations.
Record Keeping Requirements
Audiometric records must be kept for at least 30 years from the date of the last entry — reflecting the long-latency nature of NIHL and its potential relevance to future workers’ compensation claims. Records must include the individual’s audiograms, the date and conditions of testing, and any referrals or follow-up actions.
Frequently Asked Questions
A worker refuses audiometric testing — are they breaking the law?
Workers have the right to refuse medical testing, including audiometric testing. The legal obligation is on the PCBU to offer testing, not to compel it. However, workers who refuse testing are responsible for the consequences of that refusal in terms of detecting their own hearing deterioration. Employers should document the offer and the refusal to protect themselves from future liability claims.
Can audiometric testing be done on-site rather than at a medical facility?
Yes — mobile audiometric testing vans and portable audiometric booths can bring testing to the workplace. This improves compliance rates (no travel required) and allows testing at optimal times (before shifts, ensuring 14-hour noise-free requirements are met). The test environment and instrumentation must still meet AS/NZS 1269.4 requirements.