Monitor workplace noise exposure, calculate TWA doses, and generate compliance reports against OSHA, NIOSH, ISO 9612, and EU standards — all from your smartphone.
Purpose-built for safety officers and industrial hygienists who need reliable, regulation-compliant noise measurements.
Continuous TWA noise dose measurement with real-time percentage tracking. Calculate 8-hour time-weighted average exposure per OSHA 1910.95, ISO 9612, or NIOSH criteria simultaneously.
IEC 61672 Class 2 sound pressure level measurement with A, C, and Z frequency weighting. Leq, Lmax, Lmin, Lpeak, and statistical levels (L10, L50, L90) with configurable integration times.
Generate professional noise assessment reports documenting measurement methodology, exposure levels, regulatory comparison, and recommended control measures. Export as PDF for regulatory submission.
Simultaneous compliance evaluation against all major occupational noise exposure standards.
US federal standard. PEL of 90 dBA TWA, action level at 85 dBA TWA. 5 dB exchange rate. Hearing conservation program required above action level.
International standard for determination and assessment of occupational noise exposure. Task-based, job-based, and full-day measurement strategies.
NIOSH recommends 85 dBA REL with 3 dB exchange rate — more protective than OSHA. Basis for best-practice hearing conservation programs.
European directive with lower and upper exposure action values of 80 dBA and 85 dBA (LEX,8h). Exposure limit of 87 dBA including HPD attenuation.
Understand the differences between OSHA, NIOSH, and EU noise exposure limits at a glance. SonaVyx evaluates your measurements against all three simultaneously.
| Parameter | OSHA 1910.95 | NIOSH REL | EU 2003/10/EC |
|---|---|---|---|
| Exchange Rate | 5 dB | 3 dB | 3 dB |
| Action Level / Lower EAV | 85 dBA TWA | 85 dBA REL | 80 dBA LEX,8h |
| PEL / Upper EAV | 90 dBA TWA | 85 dBA REL | 85 dBA LEX,8h |
| Exposure Limit | 90 dBA TWA | 85 dBA REL | 87 dBA LEX,8h* |
| Peak Limit | 140 dB SPL | 140 dB SPL | 140 dB C-peak |
| Monitoring Required | >= 85 dBA TWA | >= 85 dBA REL | >= 80 dBA LEX,8h |
| HPD Required | >= 90 dBA TWA | >= 85 dBA REL | >= 85 dBA LEX,8h |
| Audiometric Testing | >= 85 dBA TWA | >= 85 dBA REL | >= 85 dBA LEX,8h |
* EU exposure limit of 87 dBA includes attenuation provided by hearing protection devices (HPD). This is unique to the EU directive.
Select or scan hearing protection devices and calculate the effective attenuation using NIOSH subject-fit derating methods. Compare NRR, SNR, and HML ratings across different HPD types to find the right protection level for each noise environment.
Noise-induced hearing loss (NIHL) remains one of the most prevalent occupational diseases worldwide. The World Health Organization estimates that over 360 million people globally have disabling hearing loss, with occupational noise exposure being a leading preventable cause. In the United States alone, OSHA estimates that approximately 22 million workers are exposed to hazardous noise levels each year, and the Bureau of Labor Statistics reports thousands of cases of occupational hearing loss annually. Effective noise measurement is the foundation of any hearing conservation program, yet traditional noise dosimetry equipment remains expensive, cumbersome, and underutilized by the organizations that need it most.
The regulatory landscape for occupational noise exposure involves several overlapping frameworks. OSHA 29 CFR 1910.95 is the enforceable US federal standard, establishing a Permissible Exposure Limit (PEL) of 90 dBA as an 8-hour Time-Weighted Average (TWA) with a 5 dB exchange rate (also called the doubling rate). This means that for every 5 dB increase above 90 dBA, the permissible exposure duration halves. The action level of 85 dBA TWA triggers hearing conservation program requirements including noise monitoring, audiometric testing, hearing protection, and employee training. NIOSH uses a more protective 3 dB exchange rate with a Recommended Exposure Limit (REL) of 85 dBA, reflecting the scientific consensus that the OSHA criteria leave a significant residual risk of hearing loss. The European Union Directive 2003/10/EC establishes three tiers: a lower exposure action value of 80 dBA daily exposure (LEX,8h), an upper action value of 85 dBA, and an exposure limit of 87 dBA that uniquely accounts for hearing protection device attenuation.
Traditional noise dosimeters cost between $500 and $3,000 per unit, and a comprehensive noise survey of a manufacturing facility may require multiple dosimeters running simultaneously across different work areas and shifts. This cost barrier means that many small and medium-sized businesses — which collectively employ the majority of workers exposed to hazardous noise — simply do not conduct adequate noise monitoring. SonaVyx addresses this gap by turning any smartphone into a noise measurement instrument. When paired with an inexpensive calibrated microphone (such as the Dayton Audio iMM-6 at $18), a smartphone running SonaVyx can deliver measurements that meet the functional requirements for occupational noise assessment. The Rust WASM audio processing engine applies A-weighting per IEC 61672 and computes LAeq, TWA dose percentage, and statistical descriptors (L10, L50, L90) in real time, with data logged continuously for the duration of the work shift.
ISO 9612:2009 defines three strategies for determining occupational noise exposure: task-based measurement, job-based measurement, and full-day measurement. The task-based approach breaks a worker's day into distinct tasks, measures each task separately, and calculates the combined daily exposure. This is ideal when tasks have distinctly different noise levels and durations are well documented. The job-based approach groups workers with similar noise exposure into homogeneous exposure groups (HEGs) and measures representative samples. Full-day measurement is the simplest conceptually — the dosimeter runs for the entire shift — but requires the most instrument time. SonaVyx supports all three strategies, guiding the safety officer through task identification, measurement duration requirements, and sample size calculations to achieve the specified measurement uncertainty.
The value of noise measurement lies not in the numbers themselves but in the actions they trigger. When SonaVyx identifies exposures above the action level, the platform generates a structured compliance report documenting the measurement methodology, instrument calibration records, measured exposure levels by work area and task, regulatory comparison against OSHA, NIOSH, and EU criteria simultaneously, and recommended engineering and administrative controls prioritized by cost-effectiveness. For exposures requiring hearing protection, SonaVyx includes an HPD calculator that applies NIOSH subject-fit derating to published NRR, SNR, and HML ratings, providing realistic estimates of the protection actually achieved in the field rather than the laboratory-rated values that overstate real-world attenuation by 25-75%. This evidence-based approach to HPD selection helps safety officers choose protection that is both adequate and practical, improving compliance with hearing conservation programs.
Turn any smartphone into an occupational noise monitoring tool. Evaluate compliance against OSHA, NIOSH, and EU standards simultaneously.