Environmental Factors That Affect Strain Gauge Performance — and How to Protect Your Measurements

Strain gauges are extremely useful for precise stress and strain measurement, but they’re also sensitive instruments. Environmental conditions — temperature swings, moisture, vibration, chemicals, electromagnetic interference and more — can degrade performance, introduce error, or cause outright failure. This expanded guide explains each major factor, how it shows up in your data, and practical steps you can take to protect your installations. For background on our services, see Sensing Systems’ strain gaging page.

Quick overview — the key environmental threats

• Temperature & thermal cycling (drift, zero-shift)

• Humidity / moisture / water ingress (corrosion, shorting)

• Vibration & mechanical shock (fatigue, wire breaks)

• Electromagnetic interference (EMI) & grounding (noise, hum)

• Chemical exposure & corrosion (material attack, adhesion loss)

• UV, abrasion & biological fouling (backing/adhesive degradation)

• Pressure & subsea conditions (seal failure, hydrostatic compression)

Each threat can interact with the others — e.g., vibration accelerates adhesive degradation in a humid environment — so mitigation is usually multi-layered.

1) Temperature & thermal cycling

What it is: steady temperatures and rapid temperature swings caused by ambient changes, heat from nearby equipment, or cyclical heating/cooling.

How it affects strain gauges:

• Changes resistance via thermal coefficients → apparent strain (zero shift).

• Differential thermal expansion between gauge, adhesive, and substrate creates false strain.

• Repeated cycling weakens adhesives and solder joints, causing long-term drift and hysteresis.

Symptoms in data: slow baseline shifts, hysteresis between heating/cooling cycles, changes in gauge factor, sudden offsets after thermal events.

Mitigation:

• Use temperature-compensated or matched-material gauges and adhesives.

• Employ bridge compensation (dummy gauges, half/full bridge configurations) and measure ambient temperature for software compensation.

• Select adhesives rated for the full operating range and follow manufacturer cure profiles precisely.

• Provide thermal insulation or shielding if the gauge is near heat sources.

2) Humidity, condensation & water ingress

What it is: moisture in the air, condensation from rapid temperature change, or direct wetting (splash, immersion).

How it affects strain gauges:

• Moisture migrates under adhesive layers and into cable glands, causing corrosion and insulation breakdown.

• Saltwater introduces electrolytic corrosion and accelerates metal attack.

Symptoms in data: erratic noise, increased leakage current, sudden spikes, progressive signal degradation, and eventual open-circuit failures.

Mitigation:

• Use conformal coatings (silicone, polyurethane) or potting compounds to seal sensors.

• For long-term immersion, use hermetically sealed assemblies or purpose-built devices rather than exposed gauges — see Sensing Systems’ under water load cells and underwater torque sensors.

• Employ marine-grade cable and sealed connectors; add strain relief and proper gland sealing.

3) Vibration & mechanical shock

What it is: continuous vibration or intermittent shocks from machinery, transport, or environmental sources.

How it affects strain gauges:

• Causes adhesive fatigue, micro-cracks in the foil grid, and cable fatigue at exit points.

• Can excite resonant modes, creating signal contamination.

Symptoms in data: repetitive noise at vibration frequencies, transient spikes, intermittent contact, or sudden signal loss.

Mitigation:

• Mechanically isolate the gauge area with dampers or isolation mounts.

• Use adhesives and backing materials rated for vibration.

• Route cables to avoid chafe; use slack loops and robust strain relief.

• If measurement bandwidth permits, apply hardware or software filtering to remove vibration-related noise without masking real events.

4) Electromagnetic interference (EMI) & grounding

What it is: electromagnetic noise from motors, VFDs, radio equipment, welders, and long unshielded cable runs.

How it affects strain gauges:

• Induces voltages on long leads and creates common-mode noise that contaminates small bridge signals.

Symptoms in data: periodic hum (50/60 Hz), broadband noise, or spikes correlated with nearby equipment operation.

Mitigation:

• Use twisted-pair, shielded instrument cables and terminate shields correctly.

• Keep sensor wiring separate from high-power conductors.

• Use differential measurement (full/half Wheatstone bridge + instrumentation amplifier) and single-point grounding to avoid ground loops.

• When needed, use isolation amplifiers or differential ADC inputs and ferrite beads on cables.

5) Chemical exposure & corrosion — and how electropolishing helps

What it is: exposure to solvents, acids, alkalis, salt, and other aggressive chemicals that attack metals, adhesives, and insulating materials.

How it affects strain gauges:

• Metal grids and solder joints corrode.

• Adhesive breakdown leads to delamination.

• Backing materials and coatings can be chemically softened or dissolved.

Symptoms in data: progressive drift, sudden change in resistance, increased noise, or catastrophic failure.

Mitigation & protective finishes:

• Choose corrosion-resistant substrate materials such as stainless steel or titanium for housings and fixtures. For stainless components, electropolishing significantly improves corrosion resistance and surface finish by removing embedded iron and smoothing the surface, which reduces crevice corrosion and biofouling.

• Consider post-finish passivation (e.g., citric acid passivation) to further improve stainless steel performance in corrosive environments.

• Use chemically compatible adhesives and apply protective potting or conformal coatings to the gauge and terminations.

6) UV, abrasion & biological fouling

What it is: sunlight exposure, mechanical abrasion from particulate flow or contact, and biological growth in marine environments.

How it affects strain gauges: polymer backing and adhesives degrade under UV; abrasion physically damages foil grids; biofouling creates uneven loading and moisture pockets.

Symptoms in data: slow loss of sensitivity, increased noise, and eventual failure.

Mitigation:

• Use UV-stable materials and protective covers.

• Apply abrasion shields or place gauges in recessed/protected locations.

• For marine deployments, design housings to reduce fouling and schedule periodic cleaning or use antifouling coatings.

7) Pressure & subsea considerations

What it is: hydrostatic pressure, pressure cycling and the presence of dissolved gases/salts at depth.

How it affects strain gauges:

• Compression of housings and cable conduits can compromise seals.

• Pressure cycling can cause micro-leaks and progressive ingress.

Symptoms in data: sudden offsets after pressurization, gradually worsening noise, or catastrophic water ingress.

Mitigation:

• For subsea applications, prefer purpose-built, pressure-rated transducers like under water load cells or underwater torque sensors rather than exposed foil gauges.

• Use pressure-compensated housings, qualified penetrators, and pressure testing in a controlled chamber before deployment.

8) Installation best practices — the single biggest factor

Many field failures are due to installation errors. Correct surface prep, proper adhesive selection, correct orientation, and careful routing/payback of cables will drastically increase lifetime performance.

Checklist:

• Clean substrate (solvent degrease, light abrasion) per manufacturer instructions.

• Choose adhesive appropriate for temperature & chemicals; follow cure profiles.

• Use correct gauge orientation and full-surface contact (no air pockets).

• Provide strain relief and avoid sharp cable bends at the gauge exit.

• Photo-document installations and log serials for future troubleshooting.

9) Electronics, bridge completion & signal conditioning

Quality signal conditioning is essential to translate small resistance changes into useful data.

Recommendations:

• Use stable bridge excitation (constant current or precision voltage reference) and monitor the excitation source.

• Employ full or half-bridge configurations and temperature compensation where possible.

• Select low-noise instrumentation amplifiers and ADCs with adequate resolution for your dynamic range.

• Implement digital filtering only after ensuring it won’t mask the signals of interest.

10) Maintenance, monitoring & calibration

Even with perfect design and installation, regular inspection and calibration are essential.

Maintenance tips:

• Establish an inspection cadence (visual check, zero/offset check, insulation resistance test).

• Recalibrate after shock events, repairs, or when environmental conditions change markedly.

• Use a NIST-traceable calibration provider to ensure measurement accuracy and compliance — see Sensing Systems’ NIST traceable calibration lab.

11) Field testing & pre-deployment validation

Before long-term use, validate sensors in conditions that simulate the real environment:

• Thermal cycling in environmental chambers

• Salt-spray testing for corrosion resistance

• Vibration testing to expected PSD levels

• Hydrostatic or pressure-chamber testing for subsea systems

These tests catch failure modes early and let you adjust sealing, adhesives, or electronics before deployment.

12) Quick troubleshooting guide (symptom → likely cause → first action)

• Slow baseline drift → thermal effects or adhesive creep → check temperature logs and re-zero; consider temperature compensation.

• Intermittent signal / dropouts → cable/chassis connection or moisture → verify connector integrity, perform insulation tests.

• High noise floor → EMI or grounding → inspect cable routing; switch to shielded twisted pair; check ground scheme.

• Sudden offset → shock/overload or water ingress → inspect mechanically and for moisture; send for calibration check.

13) Real-world examples

• Subsea mooring tension monitoring: purpose-built sealed load cells and torque sensors, redundant penetrators, and pressure chamber-tested assemblies.

• Aerospace thermal-cycle testing: temperature-compensated bridges, dedicated thermal shrouds, and frequent calibration verification.

• Factory automation with heavy vibration: isolation mounts, reinforced bonding, and routed cable trays with strain relief.

Conclusion & next steps

Environmental threats to strain gauges are real but manageable. The right combination of material selection, protective finishes, robust sealing, careful installation, and disciplined maintenance/certification will keep your measurements reliable for years.

If you need help with design, protective packaging, or pre-deployment testing, contact Sensing Systems’ strain gaging team via our strain gaging services page. And if you require post-installation assurance, we operate a dedicated NIST-traceable calibration lab to keep your system in spec.