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Ultrasonic Leak Detection

Detect compressed air, steam, and vacuum leaks using ultrasonic sensors. Quantify leak costs and prioritize repairs based on energy waste.

Solution Overview

Detect compressed air, steam, and vacuum leaks using ultrasonic sensors. Quantify leak costs and prioritize repairs based on energy waste. This solution is part of our Maintenance category and can be deployed in 2-4 weeks using our proven tech stack.

Industries

This solution is particularly suited for:

Manufacturing Food & Beverage Pharma

The Need

Compressed air, steam, and vacuum leaks represent the largest invisible energy waste in industrial facilities worldwide. A manufacturing plant operating 40 compressed air-consuming machines, with an average system pressure of 100 PSI, will experience 15-25% energy loss through undetected leaks. A single 3mm (1/8 inch) leak in compressed air systems costs $2,600-3,200 per year in wasted energy—the equivalent of running a full-time industrial motor continuously with zero production output. A 6mm (1/4 inch) leak costs $10,400-12,800 annually. Most facilities have 20-40 active leaks at any time, collectively wasting $200,000-500,000 per year in compressed air energy alone. In steam systems, the cost multiplies: a single 3mm steam leak wastes 5-8 tons of steam daily, equivalent to $15,000-25,000 monthly in fuel cost and water treatment chemicals. Vacuum leaks in pharmaceutical clean rooms or food processing lines cause equipment malfunction, product contamination, and production stoppages. Yet these leaks remain invisible to human operators because compressed air, steam, and vacuum are silent and colorless. Operators walk past leaking equipment hearing only quiet hissing, unable to locate the leak source or quantify the waste. Traditional leak detection relies on soapy water bubble tests—spraying soapy water onto suspected surfaces and watching for bubbles. This manual method is labor-intensive, requires experienced technicians, locates leaks slowly, and often misses subtle leaks that don't produce visible bubbles. A maintenance technician manually testing an entire facility for leaks requires 8-16 hours, costs $800-2,000 in labor, and still discovers only 60-70% of actual leaks. Facilities typically perform leak detection audits annually, if at all, meaning leaks continue for 6-12 months before detection and repair.

The financial consequences of undetected leaks compound across facility operations. Compressed air is one of the most expensive utilities in manufacturing—approximately $0.04-0.08 per CFM (cubic foot per minute) depending on electricity costs and compressor efficiency. A facility with 40 CFM of leakage running continuously at 100 PSI costs $14,000-28,000 annually in wasted electricity. For a mid-size manufacturing plant, this approaches 20-40% of total compressed air utility costs. The impact extends beyond direct energy waste. Leaks reduce system pressure, forcing air compressors to run longer and more frequently to maintain minimum operating pressure. Extended compressor runtime increases maintenance needs, shortens equipment life (adding $5,000-20,000 annually in premature maintenance), and reduces production equipment efficiency—pneumatic tools and automation systems designed to operate at 100 PSI perform poorly at 85-90 PSI, slowing production cycles by 5-10%. The hidden cost of reduced production efficiency often exceeds direct energy waste. Additionally, in pressurized systems operating at reduced pressure, moisture condensation increases, water contamination reaches downstream equipment faster, accelerating component wear and failure.

Regulatory and compliance pressures intensify the problem. ISO 50001 (Energy Management Systems) requires facilities to identify and address significant energy consumption sources—compressed air leaks qualify as major opportunities. EPA ENERGY STAR Manufacturing guidelines mandate compressed air system audits and leak repair as part of facility energy management. Pharmaceutical facilities regulated by FDA 21 CFR Part 11 must document system integrity and equipment performance—undetected vacuum leaks leading to clean room compromises create regulatory findings. Food safety regulations (HACCP, SQF) require preventing physical contamination—steam line leaks causing condensate intrusion into food products create safety incidents. The ideal solution continuously detects compressed air, steam, and vacuum leaks using ultrasonic sensors, localizes leaks to specific equipment locations, quantifies leak rates in CFM or L/min, calculates energy waste in monetary terms, prioritizes repairs by impact, and tracks repair execution to confirm resolution.

The Idea

An Ultrasonic Leak Detection system transforms manual, ineffective leak detection into continuous, quantitative leak identification that prevents energy waste worth thousands of dollars monthly. The system deploys ultrasonic sensors at facility locations where compressed air, steam, or vacuum equipment operates. Ultrasonic sensors detect high-frequency sound emissions (40,000 Hz and above) characteristic of leaking pressurized gases and liquids. Unlike audible sound equipment (human hearing range 20-20,000 Hz), ultrasonic sensors detect the turbulent noise signature generated when pressurized gas escapes through an orifice, regardless of acoustic environment. A noisy manufacturing floor with machinery operating at 80-90 dB sound level becomes silent at ultrasonic frequencies, enabling leak detection even in high-noise environments where manual soapy-water testing fails.

The system performs continuous leak detection by monitoring ultrasonic frequency bands (40-100 kHz) where compressed air leaks, steam leaks, and vacuum leaks each produce characteristic signatures. Compressed air leaks generate sharp, high-frequency ultrasonic pulses as turbulent air escapes through the orifice, creating a distinctive "chirping" ultrasonic signature at 45-65 kHz. Steam leaks produce broadband ultrasonic energy (50-90 kHz) with rapid fluctuations as hot steam molecules collide during decompression. Vacuum leaks generate lower-frequency ultrasonic signals (40-55 kHz) with distinctive modulation patterns as external air is pulled inward. Fixed ultrasonic sensors deployed throughout the facility continuously monitor these frequency bands, identifying leak events automatically. When sensors detect ultrasonic energy matching leak signatures, the system triangulates leak location using multiple sensor readings and acoustic signal timing—sound travels at known speed through air, so by measuring signal arrival time at multiple sensors, the system calculates leak 3D position within 1-3 meters accuracy. This localization capability transforms detection from "there is a leak somewhere" into "there is a 3mm leak at equipment coordinates X, Y, Z—specifically the inlet check valve of Air Compressor Unit 3."

The system quantifies leak rates by analyzing ultrasonic signal amplitude and frequency content. Leak rate in CFM (cubic feet per minute) is proportional to ultrasonic signal intensity—a larger orifice generates louder ultrasonic noise, corresponding to higher leak rate. The system correlates ultrasonic signal amplitude with system pressure (measured from connected pressure sensors), air/steam temperature, and gas properties to calculate absolute leak rate. Industry standard correlations (ISO 9614 acoustic measurement standards) enable conversion from ultrasonic signal amplitude to volumetric flow rate: a 1mm leak at 100 PSI flows approximately 3-5 CFM, a 3mm leak flows 25-35 CFM, a 6mm leak flows 100-140 CFM. The system continuously monitors these correlations, updating leak rate estimates as system pressure changes. When pressure drops from 110 PSI to 95 PSI, the system recalculates leak rates accordingly, maintaining accuracy across dynamic operating conditions.

The system calculates energy cost of each detected leak using facility-specific utility costs. For compressed air, the system multiplies leak rate (CFM) by cost per CFM ($0.04-0.08 per CFM) and hours of operation to calculate daily, weekly, monthly, and annual energy waste cost. A 30 CFM leak at a facility with $0.06 per CFM electricity costs, operating 16 hours daily (excluding nights when compressed air systems shut down), costs approximately: 30 CFM × $0.06 × 16 hours × 250 working days = $72,000 annually. The system displays this cost prominently: "Air Compressor Unit 3 inlet check valve leak costs $6,000/month in wasted energy." This quantified cost creates executive visibility into the problem and justifies repair investment. For steam systems, the system multiplies leak rate by fuel cost per ton of steam (typically $8-15 per ton) and energy content of steam to calculate monetary impact. For vacuum systems (more challenging to quantify), the system calculates equivalent compressor runtime increase required to maintain vacuum level against the leak, converting to energy cost.

The system prioritizes repairs by calculating return-on-investment for each leak repair. A 30 CFM leak costing $72,000 annually to repair may cost $200-500 in labor and materials (replacement check valve), yielding ROI of 144-360x (payback in 1-3 days). A 0.5 CFM leak costing $1,200 annually to repair may cost $300 in labor, yielding ROI of 4x (payback in 3 months). The system ranks leaks by payback period: "Priority 1: Inlet check valve leak (30 CFM, $72k/year, 1-day payback), Priority 2: Dryer outlet seal leak (8 CFM, $19k/year, 5-day payback), Priority 3: Secondary regulator diaphragm leak (2 CFM, $4.8k/year, 25-day payback)." Maintenance teams fix high-priority leaks first, maximizing energy savings per maintenance hour invested. For facilities with budget constraints, this prioritization ensures limited maintenance resources address the highest-impact issues.

The system provides real-time leak dashboards showing facility-wide leak inventory, total energy cost (sum of all leaks), top 10 leaks by cost impact, and time-to-value for repair execution. Mobile apps enable field technicians to receive leak alerts, view location maps with GPS guidance to leak sites, review recommended repair procedures for each equipment type, and log repair completion. When a technician repairs a leak, the system monitors that equipment location for ultrasonic signal changes—if leak signature disappears after repair, the system confirms repair success and updates analytics: "Inlet check valve leak repaired 2025-12-28, energy savings $72,000/year confirmed." If ultrasonic signals persist, the system alerts: "Repair completed but leak signals still detected—verify repair completeness or replacement valve may be defective."

The system integrates with facility compressed air system design documentation, equipment manufacturer specifications, and maintenance records to provide context-aware leak diagnostics. A leak at the air compressor inlet check valve differs fundamentally from a leak at a pneumatic tool quick-disconnect. The system recognizes equipment types and suggests root causes: inlet check valve leaks typically indicate valve seal degradation (maintenance fix: replace internal seals), while quick-disconnect leaks typically indicate worn coupling poppet (maintenance fix: replace coupling or use different connector type). The system recommends preventive actions: "Quick-disconnect leak detected—recommend switching to flat-face couplers that self-seal when disconnected, preventing future leaks during tool changeovers." Integration with spare parts inventory ensures replacement parts are stocked at all times: "Air Compressor Unit 3 inlet check valve—currently 0 units in inventory, 2-week procurement lead time—recommend ordering 2 units for inventory buffer and emergency repair readiness."

How It Works

flowchart TD A[Ultrasonic Sensors
Deployed Facility-Wide
40-100 kHz Detection] --> B[Continuous Passive
Acoustic Monitoring] B --> C[Detect Leak
Ultrasonic Signature] C --> D[Transmit Waveform
to Backend] D --> E[Store in SQLite
Immutable Log] E --> F[Acoustic Localization
Beamforming] F --> G[Triangulate Leak
Location X,Y,Z] G --> H[Correlate to
Equipment Database] H --> I{Leak Detected?} I -->|No| J[Continue
Monitoring] J --> B I -->|Yes| K[Calculate Leak Rate
CFM from Amplitude] K --> L[Measure System
Pressure & Temp] L --> M[Quantify Energy Cost
Annual Waste] M --> N[Calculate Repair
ROI & Payback Period] N --> O[Rank by Priority
High ROI First] O --> P[Generate Maintenance
Work Order] P --> Q[Assign to Technician
with Location Map] Q --> R[Technician Performs
Leak Repair] R --> S[System Monitors
Leak Location] S --> T{Leak Signal
Eliminated?} T -->|Yes| U[Confirm Repair
Success] U --> V[Calculate Avoided
Annual Cost] V --> W[Real-Time Dashboard
Shows Energy Savings] W --> J T -->|No| X[Alert: Repair
May Be Incomplete] X --> Y[Generate Follow-Up
Work Order] E -.->|Historical Data| Z[DuckDB Analytics
Identify Patterns] Z --> AA[Root Cause Analysis
& Preventive Strategy]

End-to-end ultrasonic leak detection system that continuously monitors for compressed air, steam, and vacuum leaks, localizes leak sources to equipment locations using acoustic triangulation, quantifies leak rates and energy costs, prioritizes repairs by ROI, tracks repair execution, and provides historical analytics for root cause analysis and preventive maintenance planning.

The Technology

All solutions run on the IoTReady Operations Traceability Platform (OTP), designed to handle millions of data points per day with sub-second querying. The platform combines an integrated OLTP + OLAP database architecture for real-time transaction processing and powerful analytics.

Deployment options include on-premise installation, deployment on your cloud (AWS, Azure, GCP), or fully managed IoTReady-hosted solutions. All deployment models include identical enterprise features.

OTP includes built-in backup and restore, AI-powered assistance for data analysis and anomaly detection, integrated business intelligence dashboards, and spreadsheet-style data exploration. Role-based access control ensures appropriate information visibility across your organization.

Frequently Asked Questions

How much does compressed air waste cost in a typical manufacturing facility? +
Compressed air waste typically costs 15-25% of total compressed air utility expense—making it one of the largest invisible energy drains in industrial facilities. For a mid-size manufacturing plant operating 40-60 compressed air-consuming machines with an annual compressed air energy bill of $200,000, leak waste costs approximately $30,000-50,000 per year. A large facility with a $1,000,000 annual compressed air bill loses $150,000-250,000 to leaks. Waste sources include: small pinhole leaks (3-6mm diameter) at 20-40 CFM each, quick-disconnect coupling leaks (5-15 CFM each) from worn poppets, pressure regulator diaphragm leaks (10-20 CFM), air dryer seals (5-10 CFM), and flexible hose micro-cracks (2-5 CFM each). A facility with 200 CFM total leak rate at 100 PSI system pressure and $0.06 per CFM electricity cost experiences: 200 CFM × $0.06 × 24 hours × 365 days = $105,120 annual energy waste. This calculation assumes continuous operation; facilities shutting down compressed air systems nights/weekends reduce waste proportionally. Compressed air costs more per unit energy than electricity because it converts only 10-30% of motor electrical input into useful pneumatic work—70-90% is lost as heat during compression. Therefore, preventing 1 CFM of leak saves $300-500 annually and prevents 3-4 kW of unnecessary motor power consumption.
How does ultrasonic leak detection locate leaks more accurately than soapy water testing? +
Ultrasonic leak detection uses physics-based acoustic triangulation to pinpoint leak location within 1-3 meters, while soapy water testing requires manual inspection within arm's reach (requiring technician to see the bubble). Acoustic localization works by deploying multiple ultrasonic sensors (3-12 sensors distributed across facility) continuously monitoring ultrasonic frequencies (40-100 kHz) where compressed air and steam leaks generate characteristic signatures. When a leak occurs, multiple sensors simultaneously detect the ultrasonic signal at different times—sound travels at 340 m/s through air, so a leak 10 meters from sensor A and 15 meters from sensor B will reach sensor A 15 milliseconds before sensor B. By measuring time-delay differences across multiple sensors, the system calculates leak 3D position using triangulation mathematics. Soapy water testing, by contrast, requires visual confirmation: technician sprays soapy water on suspected surfaces and watches for bubbles. This method has fundamental limitations: (1) technician must be within arm's reach of the leak, (2) technician must see the leak surface (not visible if leak is inside a closed manifold or inaccessible location), (3) bubbles are visible only if leak rate exceeds ~0.5 CFM (smaller leaks don't produce visible bubbles), (4) testing is time-consuming (a facility audit requires 8-16 hours of technician time), (5) technician must have experience recognizing subtle bubbles in adverse conditions. Ultrasonic systems overcome all these limitations: sensors detect leaks remotely (no technician proximity required), detect leaks inside closed equipment (ultrasonic signals propagate through metal), detect leaks down to 0.1 CFM (far smaller than soapy water capability), test continuously (24/7 automated monitoring vs. manual annual audits), and provide objective quantified data (leak rate, location coordinates) rather than subjective bubble observations.
How accurate is ultrasonic leak rate quantification in CFM? +
Ultrasonic leak rate quantification achieves accuracy of ±15-25% depending on system pressure stability, acoustic environment, and orifice geometry. Leak rate (CFM) is calculated from ultrasonic signal amplitude using empirical correlations: acoustic power radiated by an orifice leak is proportional to (pressure drop)^1.5 × orifice diameter^2. By measuring acoustic power (ultrasonic sensor signal amplitude calibrated against known reference sources) and measuring system pressure with pressure transducers, the system calculates implied orifice diameter and volumetric flow rate. Accuracy sources of error: (1) acoustic environment variation—ultrasonic signal reflections from nearby surfaces create constructive/destructive interference, affecting measured signal amplitude ±10-20%, (2) pressure transducer accuracy—±2-3% typical, (3) temperature effects—ultrasonic attenuation in air varies with humidity and temperature, requiring temperature compensation, (4) orifice geometry assumptions—calculation assumes sharp-edged circular orifice, but real leaks may have irregular geometry affecting flow pattern. Despite these uncertainties, ±15-25% quantification accuracy is sufficient for practical maintenance: distinguishing high-impact 30 CFM leaks (worth $72,000/year) from low-impact 1 CFM leaks (worth $2,400/year) is reliable even with 25% uncertainty—a 25 CFM leak will cost between $54,000-90,000 annually regardless of ±25% error band. For comparison, soapy water testing provides only binary leak detection (leak present or absent) with no quantification. Organizations pursuing maximum accuracy can correlate ultrasonic measurements with direct flow metering: measure compressed air volume manually using a bag test or turbine meter, then correlate measured flow rate to simultaneous ultrasonic signal amplitude, creating facility-specific calibration curves. Post-calibration accuracy improves to ±8-12%.
What are the main differences between compressed air leaks, steam leaks, and vacuum leaks from a detection perspective? +
Compressed air, steam, and vacuum leaks generate distinctly different ultrasonic signatures enabling system differentiation and specialized analysis. Compressed air leaks generate sharp, rapid ultrasonic pulses (45-65 kHz center frequency) as turbulent air exits through the orifice—the ultrasonic signal is characterized by short-duration impulses repeating at frequencies related to turbulence vortex shedding. Pressure drop across the orifice is the dominant energy source, so leak intensity is proportional to system pressure. Steam leaks produce broadband ultrasonic energy (50-90 kHz) with rapid amplitude fluctuations as high-temperature steam molecules decompressing create violent molecular collisions. Steam leaks are louder ultrasonically than compressed air leaks at equivalent pressure because steam undergoes phase-change (liquid-gas transition), releasing additional energy. Steam also shows strong temperature correlation: warmer steam (higher temperature, more energy) produces louder ultrasonic signals than cool steam. Vacuum leaks generate lower-frequency ultrasonic signals (40-55 kHz) with distinctive modulation patterns—external air being pulled into vacuum creates different turbulence pattern than pressurized gas escaping outward. Vacuum leak intensity is proportional to pressure differential (atmospheric pressure minus vacuum pressure). These signature differences enable the system to classify leak type automatically: "Detected ultrasonic signature at 48 kHz with characteristic impulse pattern indicates compressed air leak." For mixed systems (facility with compressed air, steam, and vacuum) the system maintains separate frequency band monitoring and classifies leaks by frequency content. Repair procedures differ: compressed air leaks typically require fixing seals or replacing check valves, steam leaks require insulation or trap repair, vacuum leaks require seal replacement. The system provides leak-type-specific repair recommendations.
How does facility system pressure affect leak detection and leak rate calculation? +
System pressure is the primary driver of leak rate—doubling pressure roughly doubles leak rate (proportional to square root of pressure drop). Ultrasonic leak intensity is proportional to velocity at the orifice (v = sqrt(2×pressure_drop/density)), which in turn drives acoustic power generation. A leak at 100 PSI (gauge) generates approximately 1.4x the ultrasonic signal and 1.4x the volumetric flow rate compared to the same leak at 50 PSI (gauge). This pressure dependency has two practical implications: (1) leak detection sensitivity varies with pressure, and (2) leak rate calculations must account for pressure changes. For leak detection sensitivity, ultrasonic systems are actually more sensitive at higher pressures (stronger signals), so detecting leaks during high-pressure operation is easier than low-pressure operation. For leak rate calculation, the system continuously measures facility system pressure and adjusts leak rate calculations accordingly. When pressure drops due to compressor drawdown or peak demand, the system recognizes: "System pressure decreased 15% (110 PSI to 94 PSI)—proportionally adjusting leak rate estimates from 30 CFM to 25 CFM." This pressure compensation ensures leak rate estimates remain accurate across dynamic operating conditions. Facilities with significant pressure variation (peak demand 120 PSI, off-peak 80 PSI) experience correspondingly large leak rate variation. The system calculates energy waste based on average operating pressure and hours at each pressure level: if facility operates at 120 PSI for 8 hours (peak demand) and 90 PSI for 8 hours (base load) daily, the system calculates waste for both conditions and sums energy cost accordingly. Pressure stability also affects cost ROI: a facility operating consistently at 110 PSI with stable compressor discharge experiences lower waste than a facility with wide pressure swings causing compressor short-cycling and acceleration of leak rates.
What is the typical payback period for repairing compressed air leaks, and how should facilities prioritize leak repairs? +
Payback periods for compressed air leak repairs typically range from 1 day to 3 months depending on leak size and repair cost. Large, easy-to-access leaks often pay back in days, while small, hard-to-access leaks may take months. Payback calculation: payback period (days) = repair cost / (daily energy waste cost). A 30 CFM leak at $0.06/CFM costing $0.30/day to repair in 1 hour of labor (labor cost $100 in material) has payback = $100 / ($30/day × 0.25 fraction of compressor uptime for the leak) = ~13 days. A 0.5 CFM leak costing $0.50/month to repair in 3 hours of labor (labor cost $150) has payback = $150 / ($0.50/month) = 300 months (very high). Facilities should prioritize repairs by payback period: (1) Priority 1 (Immediate repair): payback <1 week—cost/benefit overwhelmingly justifies immediate action, (2) Priority 2 (Schedule within 1 month): payback 1-4 weeks—should execute during planned maintenance, (3) Priority 3 (Schedule opportunistically): payback 1-3 months—batch with other low-priority work to reduce technician travel time, (4) Priority 4 (Defer): payback >3 months—evaluate whether repair cost can be reduced (e.g., contractor discount, bulk parts purchase). For many facilities, Priority 1 and Priority 2 leaks (short payback) represent 70-80% of total leak cost, but only 20-30% of leak count—focusing on high-impact leaks first yields maximum energy savings per technician hour invested. Some facilities implement "leak elimination sprint" initiatives where a team dedicates 1-2 weeks to systematically repairing all Priority 1 and Priority 2 leaks (100-200 leaks at large facilities), achieving energy savings of $200,000-500,000 annually. Post-repair, facilities should monitor prioritization trending: if Priority 1 leaks re-appear frequently, indicates recurring equipment issues requiring preventive redesign rather than just repair.
How does ultrasonic leak detection integrate with compressed air system design to prevent leaks proactively? +
Ultrasonic leak detection provides quantified data about which equipment types fail most frequently, enabling root cause analysis and preventive redesign. Historical leak analysis reveals systematic failure patterns: "In the past 24 months, 15 leaks have occurred at quick-disconnect couplings (location category 1), 12 at check valves (category 2), 8 at regulator diaphragms (category 3)." These patterns indicate systemic vulnerabilities in equipment design or specification for the facility's operating conditions. Quick-disconnect coupling leaks (most common) typically indicate: facility using general-purpose couplers unsuitable for continuous pressurization, technician-induced wear from frequent connect-disconnect cycles, poppet design inadequate for pressure/temperature range, or moisture contamination causing corrosion and seal degradation. Solutions include: (1) upgrade to flat-face couplers that self-seal when disconnected (prevent leaks during changeovers), (2) upgrade to stainless-steel poppets resistant to corrosion, (3) install better air dryers reducing moisture content downstream (moisture causes poppet corrosion), (4) implement moisture traps at all quick-disconnect locations. Check valve leaks indicate: cracking and leakage of internal ball or poppet (normal wear), inadequate seating surface (manufacturing defect), inappropriate valve type for application (globe valve used as check valve), or debris lodging in valve seat (contamination). Solutions include: (1) specify premium check valves with extended service life for critical applications, (2) upgrade to zero-leakage check valves (poppet design allowing <1 CFM leakage over service life), (3) implement upstream filtration preventing debris from reaching valve seats, (4) establish change-out intervals (replace all check valves >3 years old proactively). Regulator diaphragm leaks indicate: diaphragm fatigue from continuous pressure cycling, chemical attack from compressed air contaminants (oil, water droplets), or manufacturing defect in the diaphragm material. Solutions include: (1) specify regulators with FEA-optimized diaphragm design resisting fatigue, (2) install coalescent filters removing oil vapor and water droplets before regulators, (3) upgrade to metal-diaphragm regulators for harsh compressed air quality. By analyzing historical leak patterns, facilities transition from reactive "repair when it fails" to proactive "prevent failure through design changes"—reducing leak frequency 30-50% within 12 months.

Deployment Model

Rapid Implementation

2-4 week implementation with our proven tech stack. Get up and running quickly with minimal disruption.

Your Infrastructure

Deploy on your servers with Docker containers. You own all your data with perpetual license - no vendor lock-in.

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