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CSA Z107.6-16: Procedure for the Measurement of Occupational Noise Exposure – Technical Overview
Ensuring accurate workplace noise assessment for hearing conservation programs
Scope and Application
CSA Z107.6-16 outlines the engineering method for determining occupational noise exposure levels in workplaces. It specifies procedures for measuring A-weighted sound levels and calculating the equivalent continuous sound level (Leq) or noise dose over a work shift. The standard applies to all work environments where employees may be exposed to noise levels that could cause hearing loss or interfere with communication.
The document is intended for use by occupational hygienists, safety professionals, and acoustical consultants. It covers both general industry and mining operations, excluding impulsive noise from weapons or explosives. CSA Z107.6-16 aligns with international practices such as ISO 9612 but includes specific provisions for Canadian regulatory requirements (e.g., Canada Labour Code, provincial OHS acts).
Technical Requirements
Instrumentation
Sound level meters or personal noise dosimeters must meet the specifications of IEC 61672-1 Class 1 or Class 2. Instruments must be field-calibrated before and after each measurement series using an acoustical calibrator that meets IEC 60942 Class 1 or 2. The frequency weighting must be A-weighting, and the time weighting must be slow or fast depending on the measurement strategy.
Measurement Strategy
The standard defines three primary strategies:
- Task-based measurement: Break the work shift into distinct tasks and measure noise levels for each. The overall exposure is calculated as the energy-average of the task Leq values weighted by task duration.
- Job-function measurement: Take multiple full-shift samples for workers in similar job categories and compute the average exposure.
- Full-shift personal sampling: Attach a dosimeter to the worker for the entire shift to directly record noise dose.
Note: When using task-based or job-function methods, be aware that the variability between workers and days must be captured. The standard requires a minimum of three representative measurements for each task or job function to ensure statistical reliability.
Microphone Placement
The microphone must be positioned on the shoulder near the ear (top of the shoulder, approximately 0.1 m from the ear canal entrance) for personal dosimetry. For area measurements, the microphone should be at the worker’s ear height (typically 1.5 ± 0.1 m above the floor) and at least 0.5 m from reflective surfaces.
| Parameter | Requirement |
|---|---|
| Frequency weighting | A-weighting (dBA) |
| Time weighting | Slow (1 s) or Fast (125 ms) as appropriate |
| Exchange rate (Q) | 3 dB or 5 dB depending on jurisdiction (default 3 dB in this standard) |
| Criterion level | 85 dBA (8-hour time-weighted average) |
| Threshold level | 80 dBA (below this, noise does not contribute to dose) |
| Measurement duration | At least 80% of the work shift (preferably full shift) |
Good practice: Always document the measurement conditions, including worker tasks, machinery settings, and any unusual noise events. This information is critical when interpreting results and verifying compliance.
Implementation Highlights
Successful implementation of CSA Z107.6-16 requires careful planning. Employers should first conduct a baseline noise survey to identify high-exposure areas. Then, using the standard’s decision tree, determine which measurement strategy is most appropriate. The standard provides guidance on sample size based on the variability of noise exposure.
One key advantage of the task-based method is its ability to identify specific contributions to overall exposure. This allows engineering controls to be targeted efficiently. However, the method requires accurate time-activity logs, which can be challenging in dynamic workplaces.
Tip: Use dosimeters with datalogging capabilities to capture time-history profiles. This data can be analyzed later to correlate noise peaks with specific activities.
Compliance Notes and Auditing
CSA Z107.6-16 is not a standalone regulation but is referenced by many Canadian occupational health and safety jurisdictions. Compliance with the standard demonstrates due diligence under the internal responsibility system. Auditors will typically check:
- Calibration records (pre- and post-measurement)
- Measurement protocol selection and justification
- Worker sampling documentation (job tasks, durations, PPE usage)
- Data analysis and reporting format
Common non-compliance findings: Failure to calibrate instruments at required intervals, insufficient sample size for variable exposures, and incorrect calculation of 8-hour TWA when shifts exceed 8 hours.
The standard includes an annex with example calculations and a reporting template. Annual reviews of the hearing conservation program should incorporate updated exposure measurements following the procedures of CSA Z107.6-16.
Frequently Asked Questions
Q: What is the difference between CSA Z107.6-16 and ISO 9612?
A: Both describe engineering methods for occupational noise exposure measurement. ISO 9612 is the international standard, while CSA Z107.6-16 adapts it for Canadian workplaces, referencing Canadian noise exposure limits and including provisions for mining and resource industries. The measurement principles and strategies are very similar.
A: Both describe engineering methods for occupational noise exposure measurement. ISO 9612 is the international standard, while CSA Z107.6-16 adapts it for Canadian workplaces, referencing Canadian noise exposure limits and including provisions for mining and resource industries. The measurement principles and strategies are very similar.
Q: Does the standard require a specific exchange rate?
A: The standard primarily uses a 3 dB exchange rate (equal energy principle), which is consistent with international practice. However, it acknowledges that some Canadian jurisdictions still apply a 5 dB exchange rate for compliance. The user must check the applicable OHS regulation.
A: The standard primarily uses a 3 dB exchange rate (equal energy principle), which is consistent with international practice. However, it acknowledges that some Canadian jurisdictions still apply a 5 dB exchange rate for compliance. The user must check the applicable OHS regulation.
Q: Can I use a smartphone app to measure worker noise exposure for compliance with CSA Z107.6-16?
A: No. Smartphone apps generally do not meet the instrumentation requirements of the standard (IEC 61672). They may be used for preliminary screening, but formal exposure determination must use an approved sound level meter or dosimeter with a valid calibration certificate.
A: No. Smartphone apps generally do not meet the instrumentation requirements of the standard (IEC 61672). They may be used for preliminary screening, but formal exposure determination must use an approved sound level meter or dosimeter with a valid calibration certificate.
This article is for informational purposes only and does not substitute for the official standard. Always refer to the latest edition of CSA Z107.6-16 and applicable legislation. — Updated 2026