IFLUIDS ENGINEERING

Noise Study as per ISO 9613 Modeling

Overview

At iFluids Engineering, we provide technically rigorous Noise Study and SoundPLAN Modeling designed for complex industrial environments. Our services are grounded in empirical acoustic science and international compliance frameworks, delivering detailed assessments that support project approval, safety assurance, and design optimization.

Why Noise Studies Matter in Industrial Settings

In refineries, gas plants, compressor stations, and metering facilities, equipment such as compressors, turbines, heaters, and valves can generate high noise levels, often exceeding 90–120 dBA at source. Prolonged exposure at these levels poses occupational hazards and environmental risks. Our noise studies help quantify these impacts and simulate propagation through realistic models to:

  • Prevent hearing loss in personnel
  • Ensure compliance with ISO 9613-2, ISO 9614-1/2, ISO 11203, ISO 15664, and OSHA 1910.95 permissible limits
  • Minimize acoustic load on nearby residential or protected areas

Our Specialized Service Capabilities

The image illustrates Specialized noise impact assessment services for industrial facilities including predictive analysis, 3D acoustic modeling with SoundPLAN, on-site measurement and model calibration, regulatory compliance verification, and noise mitigation strategy engineering
Industrial Noise Impact Assessment and Mitigation Services

Predictive Noise Impact Assessment

  • Normal Operations Analysis: Evaluation of continuous noise emissions from equipment operating at design conditions.
  • Emergency Scenario Simulation: Includes PSV discharges, blowdown events, and relief conditions where noise can exceed 115–125 dBA.
  • Receiver Grid Mapping: Placement of receivers at boundary walls, control rooms, walkways, and sensitive zones to assess SPL.
  • Exposure Zoning: Mapping SPL contours (>85 dBA, >90 dBA, >100 dBA) to classify areas requiring PPE, restricted access, or engineering controls.

SoundPLAN 3D Acoustic Modeling

  • Emission Input Modeling: Equipment characterized by sound power level (PWL) and octave band data. Emission angles (directivity) and elevation adjusted to reflect true source behavior.
  • Propagation Algorithms: ISO 9613-2 method for outdoor propagation, accounting for geometric divergence, atmospheric absorption, ground attenuation, and barrier diffraction.
  • Reflection/Absorption Coefficients: Set per material specifications (concrete, steel, insulation, vegetation).
  • Topographical and Meteorological Inputs: Includes site elevation, terrain slope, prevailing wind direction, and ambient temperature layers.

Instrumented On-site Measurement & Model Calibration

  • Noise Logging: Sound level meters (Type 1, IEC 61672 Class 1) used to record LAeq, LAmax, and octave bands over representative operating conditions.
  • Calibration Protocol: Calibrated with a 94 dB reference source before and after each session.
  • Spot Mapping: Measurement grid covers locations near major equipment and boundary receptors; spatial data geo-referenced for SoundPLAN overlay.
  • Model Tuning: Measured values compared to simulated SPL for error correction within ±2 dB accuracy range.

Regulatory Compliance Verification

  • ISO 9613-2, ISO 1996-2, ISO 9614-1/2, ISO 11200/11203: Ensures methodology adheres to globally accepted acoustic modeling standards.
  • OSHA 29 CFR 1910.95: Time-weighted average exposure (TWA) and allowable exposure durations are calculated for occupational zones.
  • Local Environmental Codes: QatarEnergy 75 dBA day/night limit at industrial boundaries; RCER-2015 and EIA permit limits applied as per region.
  • BS 4142 and ISO 15665: Used where residential proximity and pipeline noise insulation is critical.
  • EEMUA 140/142: Referenced for noise measurement and acoustic pipeline insulation guidelines.

Noise Mitigation Strategy Engineering

  • Source Control: Recommendations include low-noise design options (e.g., centrifugal compressors over reciprocating, low-noise valves).
  • Path Control: Acoustic louvers, silencers, and barriers designed using insertion loss (IL) tables.
  • Receiver Protection: Control room façade upgrades (e.g., triple glazing, acoustic cladding) proposed where LAeq > 65 dBA at façades.
  • Design Feedback Loop: Re-simulated scenarios with proposed mitigation to demonstrate effectiveness (≥10 dB reduction typical).

SoundPLAN Modeling Methodology

Flowchart showing SoundPLAN Modeling Methodology with five main steps: Source Characterization, Geometry & Material Modeling, Grid and Receptor Placement, Simulation Execution, and Result Verification and Compliance Reporting.
SoundPLAN Modeling Methodology – from Source Characterization to Compliance Reporting
  1. Source Characterization
    • Sound Power Level (Lw) specified in octave bands (63 Hz to 8 kHz)
    • Emission type defined: point source (pump), line source (piping), area source (cooling bay)
    • Directivity index and mounting height accurately represented
  2. Geometry & Material Modeling
    • 3D CAD-based layout imported or manually constructed
    • Structure surfaces assigned specific reflection coefficients (e.g., Steel: 0.7, Concrete: 0.6, Vegetation: 0.2)
  3. Grid and Receptor Placement
    • Receivers placed at operator walkways (1.5 m height), building façades (4 m), site boundaries (5 m intervals)
    • Grid resolution optimized to 2–5 m spacing for high accuracy in complex layouts
  4. Simulation Execution
    • SPL maps generated in LAeq and LAmax formats for multiple scenarios (normal, emergency, mitigated)
    • Isopleths at 5 dB intervals used to define exposure zones
  5. Result Verification and Compliance Reporting
    • Model outputs validated against measurement where applicable
    • Summary tables for exceedance, mitigation effectiveness, and final compliance statement

Typical Applications

  • Compressor Packages: Fuel gas, booster, inlet
  • Heater Systems & Pressure Reducing Stations (PRS)
  • Control Buildings and Switchgear Rooms
  • Tank Farms and NGL Loading Bays
  • Scraper Stations, Jetty Terminals, Pig Launchers

Standards and Tools Applied

StandardPurpose
ISO 9613-2Outdoor sound attenuation calculation
ISO 9614-1/2Determination of sound power using intensity methods
ISO 11203Emission sound pressure at workstations
ISO 15664Open plant noise design methodology
ISO 15665Acoustic insulation standards for piping systems
ISO 11546-2Evaluation of enclosure insulation performance
BS 4142Assessment of industrial noise near residential zones
EEMUA 140/142Acoustic measurement and industrial pipeline insulation standards
OSHA 29 CFR 1910.95Occupational exposure limits
RCER-2015, QP-STD-V-004Regional boundary noise limits
SoundPLANFull-spectrum acoustic modeling & isopleth generation

Why Choose iFluids Engineering?

  • Deep industry experience in compressor and metering station noise prediction
  • Measurement-calibrated models to ensure real-world accuracy
  • Region-specific regulatory expertise (Qatar, KSA, UAE, India)
  • Design-phase feedback for acoustic control integration in FEED/EPC stages
  • Multilingual reporting formats compliant with client and authority standards

Get in Touch

Ensure your industrial project is acoustically compliant, safe, and future-ready.

Contact iFluids Engineering to commission a detailed Noise Study and SoundPLAN Model today.

Noise exposure isn’t just a compliance matter—it’s an engineering obligation. Partner with iFluids Engineering for technically certified, audit-ready acoustic modeling solutions.