Thermographic testing, often called thermal imaging or infrared scanning, is a non-contact method of detecting heat signatures in electrical systems. Switchboards, which form the central distribution points for electrical circuits in commercial and industrial facilities, require regular thermographic inspections.
These inspections help identify early warning signs of electrical faults, such as hot spots or overloaded circuits, that could otherwise lead to serious operational failures or fires.
But how frequently should thermographic testing be performed on switchboards? This question is best answered by examining the operational context, the risk environment, regulatory expectations, and the equipment’s history. Below, we provide detailed guidance to help organisations determine the proper testing schedule tailored to their needs.
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Recommended Testing Frequency
Annual Testing – The Industry Baseline
In most general commercial environments, switchboards should be tested thermographically at least once every 12 months. This annual interval serves as a foundational safety measure for detecting emerging faults and verifying the reliability of connections and components.
- Annual testing helps uncover loose terminals, insulation wear, or imbalances that may not yet show visible signs but are building toward failure.
- It ensures that switchboards comply with insurance conditions and general workplace safety standards.
- Facilities with stable loads, well-maintained equipment, and clean environments are well-served by this frequency.
This annual testing baseline aligns with what many insurers and regulatory agencies recognise as acceptable preventative maintenance.
More Frequent Inspections For Critical Operations
Some facilities require more stringent monitoring. Where operations are critical to business continuity or public safety, thermographic testing should be increased to every 6 or 3 months, depending on circumstances.
Facilities needing enhanced inspection frequency include:
- Hospitals and healthcare centres, where switchboard faults could compromise patient care.
- Data centres, where downtime results in substantial financial loss.
- Food processing or chemical plants, where strict temperature and operational controls must be maintained.
- Manufacturing plants with 24/7 operations and high energy consumption.
Switchboards in these facilities operate under higher loads, often without scheduled shutdowns, meaning faults must be caught early through regular imaging.
Compliance With Industry Standards
Local Regulatory And Insurance Requirements
In Australia, there is no single, nationally binding law mandating the frequency of thermographic testing. However, several standards, codes of practice, and safety regulations create a strong case for routine inspections:
- Safe Work Australia recommends that thermal imaging be part of an effective electrical maintenance plan.
- Work Health and Safety (WHS) legislation across states and territories places duty-of-care obligations on employers to identify and manage workplace risks, including electrical hazards.
- Insurers often require annual or biannual thermographic reports for high-risk properties. Failure to conduct and document inspections can jeopardise claims if an electrical incident occurs.
Testing frequencies may also be specified in compliance audits, energy management programs, or safety management systems. In many cases, annual reporting is the minimum acceptable standard for commercial risk control.
International Reference: NFPA 70B
Although developed in the United States, NFPA 70B (Standard for Electrical Equipment Maintenance) is a globally respected guide that Australian businesses use for benchmarking. It recommends:
- Annual thermographic inspections are performed on all energised electrical systems under normal conditions.
- Semi-annual or quarterly testing for critical systems or those exposed to adverse conditions.
Aligning with NFPA 70B enhances risk management and global compliance readiness for Australian businesses with international ties or high operational safety standards.
Factors That Influence Inspection Frequency
While annual inspections are appropriate for many facilities, several variables can necessitate more frequent testing. These factors should be assessed case-by-case to determine an optimal schedule.
Operational Load And Equipment Criticality
Switchboards under higher load are at greater risk of overheating and stress-related failure. For example:
- A commercial kitchen may have equipment cycles that place uneven or heavy loads on circuits.
- In a manufacturing site, motors and machinery connected through the switchboard may draw variable and intensive power levels throughout the day.
Critical switchboards—those whose failure would cause substantial disruption or safety hazards—require more proactive oversight. When such infrastructure forms the backbone of business continuity, the case for quarterly or semi-annual inspections is clear.
Age And Reliability Of Equipment
Ageing switchboards are prone to more frequent faults:
- Older components are more likely to experience resistance-related heating, even without visible wear.
- Outdated insulation materials, corroded terminals, and older fuses may all create fault conditions detectable by thermal scans.
As a rule, equipment over 10 years old should be inspected at least every 6 months unless upgraded or recently overhauled. Increased testing frequency is not just recommended—it’s essential for switchboards that have experienced significant wear or lack a consistent maintenance record.
Environmental Exposure
Facilities in harsh environments tend to place more stress on electrical infrastructure. Switchboards in these locations degrade faster and may require thermal inspections more frequently:
- Humidity and moisture accelerate corrosion and can reduce insulation resistance.
- Dust and particulate matter can block cooling airflow and create conductive paths on insulating surfaces.
- Salt air in coastal areas contributes to faster electrical corrosion and component deterioration.
- Vibration and movement, such as in industrial or mining sites, can loosen terminals and cause alignment issues.
In such cases, inspections every 3 to 6 months are justified, even in systems that would otherwise qualify for annual testing.
Maintenance History And Known Faults
A key consideration is whether the switchboard or broader system has experienced faults in the past:
- Even if corrected, facilities with a history of thermal anomalies are considered higher risk.
- Fault recurrence is a known issue, especially in systems with fluctuating loads or legacy wiring.
- A new anomaly detected in a previous inspection should be retested within 3 months to confirm that the issue was resolved and no new problems have developed.
If thermal imaging reports show regular deviations or if repairs have been recent or frequent, adjust your inspection frequency to prevent possible failures.
Insurance And Business Risk
From a business continuity and insurance standpoint, periodic inspections provide proof that equipment is being maintained responsibly:
- A facility unable to produce recent thermographic testing reports during an insurance claim for an electrical fire may be denied coverage.
- Documented preventative inspections will benefit companies in sectors with strict risk control requirements (e.g., energy, healthcare, logistics).
- For public-facing organisations or critical infrastructure providers, demonstrating proactive switchboard management is also part of reputational risk mitigation.
Insurance underwriters may recommend inspection frequency or tie it to policy conditions. Failure to adhere to a defined thermal imaging schedule in some sectors can void coverage or trigger premium increases.
Conclusion
Determining how often you should perform thermographic testing on your switchboard is not a one-size-fits-all decision. While annual inspections are generally sufficient for low-risk environments with stable electrical demand, many situations warrant more frequent testing.
Factors such as equipment criticality, environmental exposure, the age of infrastructure, and operational risk all influence the ideal inspection schedule.
The purpose of thermal imaging is simple: detect early-stage faults before they evolve into failures. This proactive approach extends the lifespan of equipment and supports workplace safety and compliance. By tailoring your inspection schedule to the realities of your facility, you safeguard not just your switchboards but also your business operations as a whole.
Frequently Asked Questions
Is Thermographic Testing Mandatory In Australia?
Thermographic testing is not legally mandated under one specific Australian law but is strongly recommended under workplace safety obligations and insurance requirements.
Regulators expect businesses to take reasonable steps to prevent electrical hazards, and thermal imaging is considered part of a sound maintenance program. Many insurers require regular thermographic inspections, especially in high-risk industries.
Can I Perform Thermographic Testing During Shutdown Periods?
Thermographic testing should occur while the switchboard is energised and under normal load. Testing during shutdowns or low-load conditions will not accurately reveal heat anomalies. The equipment must be fully operational to detect issues like overloaded circuits or loose connections.
What Happens If A Hot Spot Is Detected During Testing?
A licensed electrician should mark the area for urgent inspection and repair if a hot spot is identified. The issue might involve a loose terminal, overloaded circuit, or faulty component, which can pose fire or equipment failure risks. A re-inspection should follow repairs to confirm the problem has been resolved.