Have You Heard of the CalCard? (And Do You Actually Need One?)
- Technical review: Thomas Jevons (Head of Training, 20+ years)
- Employability review: Joshua Jarvis (Placement Manager)
- Editorial review: Jessica Gilbert (Marketing Editorial Team)
- Last reviewed:
- Changes: Updated for EAS 2024 ongoing calibration verification requirements and 2026 digital tool integration trends
Walk into any electrical wholesaler and you’ll see them hanging near the till. Credit card sized. Gold contacts. Around twenty quid. The CalCard.
Some sparks swear by them. Keep one in their wallet, test their MFT monthly, log the results religiously. Others reckon they’re pointless if you’re getting annual calibration anyway. A few have bought one, used it twice, and it’s been gathering dust in a toolbox ever since.
Here’s the thing: the CalCard isn’t about replacing calibration. It’s about proving your meter hasn’t drifted since the last time it was calibrated. That distinction matters more in 2026 than it did five years ago, but not for the reasons most people think.
This isn’t a sales pitch. It’s an honest breakdown of what a CalCard actually does, who genuinely needs one, and whether the £25 investment makes sense for your specific situation.
What a CalCard Actually Is (Without the Marketing Fluff)
The CalCard is a laminated PCB with precision resistors built into a credit card form factor. That’s it. No electronics. No batteries. Just fixed resistance values you can test against.
It provides ten reference points:
Continuity values: 0.25Ω, 0.5Ω, 1Ω, 2Ω, 5Ω
Insulation values (tested up to 1500V): 0.5MΩ, 1MΩ, 2MΩ, 10MΩ, 20MΩ
You touch your MFT probes to the gold contact pads, record what the meter displays, and compare it against the printed values. If they match within acceptable tolerances, your meter’s continuity and insulation functions are reading consistently. If they don’t, you’ve got a problem.
The card itself doesn’t “calibrate” anything. It doesn’t adjust your meter. It doesn’t make it more accurate. It’s a reference point, like checking your bathroom scales against a known weight.
Calibration vs Verification (The Distinction That Actually Matters
Here’s where confusion happens. People use “calibration” and “verification” interchangeably. They’re not the same thing.
Formal calibration means sending your meter to a UKAS-accredited lab where it’s tested against traceable national standards, adjusted if necessary, and certified. This typically costs £80-£120 annually and takes a week while your meter’s away.
Verification means checking your meter against a known reference to confirm it hasn’t drifted since calibration. The CalCard does verification, not calibration.
Think of it this way: calibration is your meter’s MOT. Verification is checking your tyre pressures and oil level before a long journey. Both matter. Neither replaces the other.
BS 7671 and the Electricity at Work Regulations 1989 require that test equipment be “suitable for the purpose” and “maintained in good order.” They don’t explicitly mandate CalCards or monthly checks. But they do require that your test results be accurate, which means proving your meter was working correctly when you recorded those readings.
"The CalCard only checks continuity and insulation functions. It can't verify your loop impedance accuracy, RCD trip times, or voltage readings. That's why it's a verification tool, not a replacement for proper annual calibration against traceable standards."
Who Actually Needs a CalCard (And Who Doesn't)
Not everyone needs one. Let’s be honest about who benefits.
You probably need a CalCard if:
You’re doing regular EICRs where test results might be challenged months later. Documentation of ongoing accuracy matters for professional indemnity.
You work alone or run your own business. You’re responsible for proving your test results are defendable. A verification log provides that proof.
You do high-volume testing work. Commercial maintenance, landlord certificates, large-scale domestic work. The more tests you conduct, the more important consistent accuracy becomes.
Your meter’s been through trauma. Dropped off a ladder. Left in a freezing van overnight. Knocked about in transit. The CalCard tells you immediately if internal components have shifted. The scope of work you’re planning to undertake, whether staying domestic-only or moving into commercial testing, affects whether verification documentation becomes essential.
You probably don’t need a CalCard if:
You’re still training under supervision for your NVQ. The assessor’s meters are the reference standard. Your responsibility is understanding the process, not maintaining the equipment yet.
You only use your meter occasionally for basic continuity checks. The risk-to-cost ratio doesn’t justify it.
You’ve got a modern MFT with built-in confidence checks and you trust them. Some newer Megger and Fluke models have internal self-verification that serves the same monitoring function.
What the CalCard Can't Do (The Honest Limitations)
Let’s address what it doesn’t check, because this is where expectations diverge from reality.
It doesn’t verify loop impedance (Zs). Your earth fault loop tests could be reading high or low and the CalCard won’t tell you. For that, you need a dedicated test socket or a full check box.
It doesn’t verify RCD trip times. Whether your RCD tests are accurate isn’t something the card can assess. Again, you’d need a proper reference socket or check box.
It doesn’t verify voltage readings. If your voltage display is showing 235V when the actual supply is 242V, the CalCard won’t detect that.
It doesn’t adjust anything. If your meter’s reading 0.3Ω when the card shows 0.25Ω, the CalCard hasn’t “fixed” anything. It’s just told you there’s a problem. You still need proper calibration.
It can’t prove legal compliance on its own. NICEIC, NAPIT, and other competent person schemes accept CalCard logs as evidence of ongoing monitoring, but they still require annual traceable calibration certificates. The card supplements, it doesn’t replace.
To be fair, most electricians don’t realise these limitations until they’ve bought one expecting it to do more than it actually does.
How Electricians Actually Use CalCards in Practice
Theory versus reality often diverge. Here’s what actually happens.
The monthly loggers: These are the organised sparks. First Monday of every month, they spend five minutes testing the CalCard, recording results in a spreadsheet or app, and moving on. They’ve got years of verification data if anyone questions a test result from 2023.
The post-trauma checkers: Most common use case. The meter takes a knock, falls off something, or gets left in the van during a cold snap. Before starting the next job, they run it against the CalCard to confirm nothing’s shifted. Peace of mind.
The assessment preparers: NVQ candidates and those approaching ECS card renewal often use CalCards specifically because assessors look favourably on documented verification practices. It demonstrates professional competence beyond just having certificates.
The “bought it once” group: They purchased it because someone said they should. Used it a few times. It’s now somewhere in the toolbox. They’re getting annual calibration anyway and figure that’s sufficient.
The reality? There’s no wrong approach here. It’s about risk management and professional standards. High-volume testers need more frequent checks than someone doing occasional domestic work.
The 2026 Reality: Modern Tools Are Changing the Game
Here’s what’s shifted since the CalCard became popular in 2009.
Built-in confidence checks have improved. Modern MFTs from Megger (MFT-X1) and Fluke (1664 FC) now include internal self-verification that runs automatically on startup. They’re not UKAS traceable, but they catch major drift issues without external tools.
Digital logging has arrived. Apps like iCertifi, CertSuite, and Verifi now track calibration dates, log verification checks, and send reminders. The physical check still happens, but the recording is automated. How you approach developing professional competence, whether through fast-track intensive training or traditional college routes, affects how early you start managing your own verification systems.
Cloud-synced compliance is emerging. Some MFTs now upload test results and self-check data automatically. The “paperless spark” is becoming reality, though the physical verification reference still matters for those without Bluetooth-enabled meters.
AI-assisted verification is coming. We’re seeing early versions of apps that analyse test result patterns over time to flag when a meter might be drifting before it fails verification checks. Not mainstream yet, but the direction is clear.
"The sparks doing well in 2026 are the ones who combine traditional verification tools like CalCards with digital logging. It's not either/or. The physical check proves accuracy, the app proves you're documenting consistently. Employers value both."
Alternatives to the CalCard (And When They Make More Sense)
The CalCard isn’t the only verification option. Here are the alternatives and their trade-offs.
Full check boxes (Di-LOG, ISS, Megger MTB7671) test continuity, insulation, loop impedance, RCD trip times, and voltage. Comprehensive but bulky and expensive (£300-£500). Worth it if you need to verify all functions, impractical if you’re mainly doing domestic work.
Dedicated test sockets installed in your workshop or home give you a known reference for loop and RCD testing. Free after installation. The limitation? Supply voltage fluctuates, so you’re not testing against a fixed reference like a CalCard provides.
Resistance decade boxes offer adjustable resistance values so you can test any value, not just the fixed points on a CalCard. More versatile but less portable and more expensive.
Built-in meter self-tests run automatically on newer MFTs. Convenient and included in the purchase price. The catch? They’re manufacturer-dependent and not independently traceable.
Digital tracking apps without hardware (Verifi, QuickBooks integration, custom spreadsheets) handle the documentation side. You still need a physical reference for the actual check, but they remove the logging burden.
The honest assessment? For most electricians, the CalCard hits the sweet spot of portable, affordable, and sufficient for demonstrating ongoing verification between annual calibrations.
Common Myths About CalCards (And What's Actually True)
Let’s address the misconceptions that persist on forums and in wholesaler conversations.
Myth: “CalCard replaces annual calibration.” Reality: It supplements, not replaces. You still need UKAS-traceable calibration annually for competent person scheme compliance. The CalCard monitors drift between those formal calibrations.
Myth: “NICEIC requires CalCards.” Reality: NICEIC requires a “system for maintaining instrument accuracy.” CalCards are one way to achieve that, but not the only way. Documented verification of any kind satisfies the requirement.
Myth: “If the CalCard reading is slightly off, the meter’s broken.” Reality: Usually it’s the test leads. Lead resistance matters, especially on low-value continuity checks. You need to null your leads before testing, otherwise you’re measuring lead resistance plus card resistance.
Myth: “CalCard values never change over time.” Reality: High-stability resistors in proper GRP housing are incredibly stable, but they’re not immune to physical damage or extreme conditions. If your card’s been bent, crushed, or exposed to moisture, the values can shift.
Myth: “You need a CalCard immediately after qualifying.” Reality: During NVQ training under supervision, the training centre’s meters are the reference. You need your own verification system once you’re responsible for signing off independent test results.
The pattern? Most myths stem from conflating verification with calibration or misunderstanding what acceptable tolerances mean.
The Professional Development Angle (Why Verification Matters for Career Progression)
This isn’t just about compliance. It’s about demonstrating professional competence.
When contractors evaluate electricians for long-term work, they’re not just checking certificates. They’re assessing whether you understand professional standards. Someone who maintains verification logs, tracks calibration dates, and can produce documentation when questioned stands out from someone who just turns up with a meter and assumes it’s accurate. Understanding professional standards like verification systems becomes more important as you progress through JIB gradings where hourly rates increase with demonstrated competence and responsibility.
Main contractors, particularly on commercial projects, increasingly scrutinise verification documentation during audits. Building Safety Act 2022 requirements have raised the bar across construction trades. Electrical testing is no exception.
The sparks earning approved electrician rates aren’t necessarily more skilled technically. Often they’re the ones who can demonstrate they maintain professional standards consistently. Verification logging is part of that package.
To be fair, this matters more for commercial and industrial work than purely domestic installations. But if you’re planning to expand your scope beyond domestic, understanding verification systems now prevents scrambling to implement them later when a main contractor demands documentation.
Should You Buy a CalCard? The Honest Decision Framework
Stop asking “do I need one?” and start asking “does the cost-to-benefit ratio make sense for my situation?”
You should buy one if:
- You conduct 5+ EICRs monthly where test results might be challenged later
- You work independently and need to prove instrument accuracy to insurers or competent person schemes
- You’ve had a meter trauma event and need immediate confirmation it’s still accurate
- You’re approaching NVQ assessment or ECS card renewal where documented verification helps
- You want peace of mind for the cost of a tank of diesel
You shouldn’t buy one if:
- You’re still in supervised training and using centre equipment
- You send your meter for calibration every 6 months and trust that frequency
- You’ve got a modern MFT with reliable built-in self-checks and you’re comfortable relying on those
- Your work volume doesn’t justify the documentation overhead
- You only use your meter for basic continuity checks occasionally
The cost is £20-£30. If that budget matters significantly, you probably don’t need it yet. If that’s negligible compared to your testing income, get one and use it. The decision isn’t complicated.
What This Means for Your Testing Practice
If you’re running your own testing work or moving toward independence, having a verification system matters. Whether that’s a CalCard, a check box, or a combination of physical references and digital logging depends on your work scope.
The key insight? Verification isn’t about the tool. It’s about demonstrating you have a system for maintaining accuracy between formal calibrations. The CalCard is just the most portable, affordable option for achieving that.
If you’re doing high-volume commercial work, you might need more comprehensive verification covering loop and RCD functions. If you’re doing purely domestic installations, a CalCard probably covers what you need.
The electricians getting this right in 2026 are the ones who’ve stopped treating verification as a compliance box-tick and started treating it as a professional standard. It’s not about what assessors demand. It’s about proving your test results are defendable if challenged months or years later.
That mindset shift, not the physical card, is what separates competent professionals from qualified technicians still learning the industry’s expectations.
Call us on 0330 822 5337 to discuss how our NVQ pathway includes training on professional testing standards, verification systems, and documentation practices that employers actually look for. We’ll explain how verification fits into the broader competence framework from NVQ through AM2 to independent practice.
What we’re not going to tell you:
- That you must buy a CalCard immediately
- That verification replaces proper calibration
- That expensive tools make you more competent
What we will tell you:
- When verification documentation becomes essential in your progression
- How to build professional practices that satisfy competent person schemes
- What employers look for when assessing testing competence
- The difference between compliance and genuine professional standards
No hype. No unnecessary tool sales. Just practical guidance on building the professional practices that support long-term career progression in electrical testing work.
References
Primary Standards and Regulations
- HSE Guidance Note GS38 (Electrical Test Equipment for Use by Electricians): https://www.hse.gov.uk/pubns/books/gs38.htm
- Electricity at Work Regulations 1989: https://www.legislation.gov.uk/uksi/1989/635/contents/made
- BS 7671:2018+A2:2022 (18th Edition Wiring Regulations): https://shop.theiet.org/bs-7671-2018-a3-2022
- IET Guidance Note 3 (Inspection & Testing): https://electrical.theiet.org/media/1696/ongoing-accuracy-of-test-instruments.pdf
- BS EN 61557 Standards (Electrical Safety in Low Voltage Distribution Systems): https://www.iec.ch/homepage
Assessment and Competence Bodies
- Electrotechnical Assessment Specification (EAS) 2024: https://electrical.theiet.org/bs-7671-18th-edition-wiring-regulations/building-regulations/electrotechnical-assessment-specification
- NICEIC Technical Guidance (Test Equipment Safety): https://niceic.com/getmedia/762576bb-a974-4882-9e25-2b2c96116db3/Safety-Through-Accuracy-of-Test-Equipment.pdf
- NAPIT Approved Contractor Scheme Requirements: https://www.napit.org.uk/
- UKAS Calibration Accreditation Standards: https://www.ukas.com/accreditation/standards/laboratory-accreditation/calibration
Manufacturer and Industry Resources
- Megger Technical Library (Instrument Maintenance): https://www.megger.com/en/support/technical-library/application-guides
- Fluke Calibration Resources: https://www.fluke.com/en-gb/learn/calibration
- Electrical Safety First Best Practice Guide 7 (Test Equipment): https://www.electricalsafetyfirst.org.uk/media/1208/best-practice-guide-7-issue2.pdf
Market and Practitioner Sources
- ElectriciansForums.net Discussion Threads: https://www.electriciansforums.net/
- Screwfix Community Forum (Calibration Topics): https://community.screwfix.com/
Note on Accuracy and Updates
Last reviewed: 28 January 2026. This page is maintained; we correct errors and refresh sources as verification tools and digital logging systems evolve. EAS 2024 requirements reflect current ongoing calibration verification standards. Next review scheduled following any significant regulatory changes to BS 7671 or competent person scheme requirements.
FAQs
What exactly is a CalCard, and what does it actually test on a multifunction tester?
A CalCard is a small, credit card-sized device containing fixed resistors used to verify the accuracy of insulation resistance and continuity measurements on multifunction testers, insulation testers, or continuity testers.
Typical CalCards include:
- Insulation resistance values: 0.5 MΩ, 1 MΩ, 2 MΩ, 10 MΩ, 20 MΩ (rated up to 1500 V)
- Continuity values: 0.25 Ω, 0.5 Ω, 1 Ω, 2 Ω, 5 Ω
When connected using test leads, the CalCard allows electricians to confirm whether the tester displays the correct readings for known resistances. This helps identify drift or faults in the instrument. It only checks resistance-based functions, supporting reliable BS 7671-compliant testing.
In practice, it is a quick spot-check tool, particularly useful after knocks, drops, or long periods of storage, helping maintain professional standards between formal calibrations.
Is a CalCard the same thing as meter calibration, or does it serve a different purpose?
A CalCard is not the same as formal meter calibration.
- Calibration involves laboratory testing against traceable national standards, usually annually, to certify overall instrument accuracy.
- A CalCard provides an interim verification of specific resistance readings only, confirming whether insulation and continuity functions remain accurate since the last calibration.
Calibration satisfies EAWR 1989 Regulation 4(2) for maintained work equipment. CalCard use supports ongoing field reliability and defensibility but cannot adjust the tester or verify other functions.
Myth clarification: A CalCard does not recalibrate a meter and does not check voltage, loop impedance, or RCD performance.
Do BS 7671 or the Electricity at Work Regulations require electricians to use a CalCard?
No regulation explicitly requires CalCard use.
- BS 7671 requires inspection and testing using instruments that are fit for purpose.
- EAWR 1989 Regulation 4(2) requires electrical work equipment to be maintained to prevent danger.
A CalCard helps demonstrate this in practice, but alternatives such as manufacturer self-tests or checksum boxes are acceptable if properly documented. Competent person schemes may expect evidence of regular checks, but CalCards themselves are not a legal requirement.
Fact vs myth: Claims that CalCards are legally required usually come from scheme guidance, not law.
Who genuinely benefits from owning a CalCard, and who can safely do without one?
Most benefit:
- Electricians carrying out frequent EICRs or periodic inspections
- NVQ learners developing competence under EAS 2024
- Contractors with multiple testers or high audit exposure
- Commercial electricians where results may be scrutinised
Can often do without one:
- Low-volume domestic installers
- Electricians relying on annual calibration and built-in tester self-checks
- Users with documented alternative verification methods
It is not essential for everyone, but it adds professionalism and defensibility where test accuracy is likely to be questioned.
What types of electrical testing does a CalCard not verify, and why does that matter?
A CalCard does not verify:
- Loop impedance
- RCD trip times
- Voltage measurement
- Phase rotation
- Earth electrode resistance
This matters because BS 7671 requires all these parameters to be tested where applicable. Relying solely on a CalCard could miss faults in other tester functions.
Key point: A CalCard is a supplementary check, not a universal validator. Full calibration and other verification methods remain essential for compliance and liability protection.
How do competent person schemes like NICEIC or NAPIT view CalCards during audits?
Schemes such as NICEIC and NAPIT generally view CalCards positively as evidence of good practice.
Auditors may:
- Accept CalCard records as proof of interim verification
- Expect them alongside, not instead of, calibration certificates
- Value documented checks after drops or damage
Lack of a CalCard is not usually penalised if alternative verification is documented, but using one strengthens professional defensibility.
Myth clarification: CalCards are recommended, not mandated, by schemes.
How often should a CalCard be used in real-world electrical testing work?
There is no fixed interval in BS 7671. In practice:
- Monthly or before major jobs is common
- Weekly for high-volume EICR work
- Quarterly for occasional testers
Use it after storage, transport, or potential damage. Always log results. Overuse can cause wear, so apply a risk-based approach suited to your workload.
Can a CalCard help protect you if test results are questioned months or years later?
Yes, to a degree.
Documented CalCard checks provide evidence that the tester was functioning correctly at the time of testing, supporting due diligence under EAWR 1989 and BS 7671. This can be valuable in disputes, insurance claims, or investigations.
However, it is not a complete safeguard. Calibration records, correct procedures, and full documentation remain essential.
Are modern multifunction testers with built-in self-checks reducing the need for CalCards?
Modern testers with internal diagnostics do reduce reliance on CalCards for basic verification. These self-checks often satisfy EAWR expectations for maintained equipment.
However, they may not replicate real resistance loads. CalCards provide independent verification, which is still valued during audits, especially where results are high-risk or contentious.
For many users, CalCards are now supplementary rather than essential.
How should an electrician decide whether the £20–£30 cost of a CalCard is worthwhile?
Consider:
- How often you test
- Whether your work is audited or scrutinised
- The risk of results being challenged later
- Whether you already use reliable self-checks
For frequent inspectors, NVQ learners, or scheme members, the cost is usually justified. For occasional domestic work, it may be unnecessary.
Decision rule: If documented verification strengthens your professional position without duplication, it’s worth it. If not, prioritise calibration and core test equipment first.
What exactly is a CalCard, and what does it actually test on a multifunction tester?
A CalCard is a small, credit card-sized device containing fixed resistors used to verify the accuracy of insulation resistance and continuity measurements on multifunction testers, insulation testers, or continuity testers.
Typical CalCards include:
- Insulation resistance values: 0.5 MΩ, 1 MΩ, 2 MΩ, 10 MΩ, 20 MΩ (rated up to 1500 V)
- Continuity values: 0.25 Ω, 0.5 Ω, 1 Ω, 2 Ω, 5 Ω
When connected using test leads, the CalCard allows electricians to confirm whether the tester displays the correct readings for known resistances. This helps identify drift or faults in the instrument. It only checks resistance-based functions, supporting reliable BS 7671-compliant testing.
In practice, it is a quick spot-check tool, particularly useful after knocks, drops, or long periods of storage, helping maintain professional standards between formal calibrations.
Is a CalCard the same thing as meter calibration, or does it serve a different purpose?
A CalCard is not the same as formal meter calibration.
- Calibration involves laboratory testing against traceable national standards, usually annually, to certify overall instrument accuracy.
- A CalCard provides an interim verification of specific resistance readings only, confirming whether insulation and continuity functions remain accurate since the last calibration.
Calibration satisfies EAWR 1989 Regulation 4(2) for maintained work equipment. CalCard use supports ongoing field reliability and defensibility but cannot adjust the tester or verify other functions.
Myth clarification: A CalCard does not recalibrate a meter and does not check voltage, loop impedance, or RCD performance.
Do BS 7671 or the Electricity at Work Regulations require electricians to use a CalCard?
No regulation explicitly requires CalCard use.
- BS 7671 requires inspection and testing using instruments that are fit for purpose.
- EAWR 1989 Regulation 4(2) requires electrical work equipment to be maintained to prevent danger.
A CalCard helps demonstrate this in practice, but alternatives such as manufacturer self-tests or checksum boxes are acceptable if properly documented. Competent person schemes may expect evidence of regular checks, but CalCards themselves are not a legal requirement.
Fact vs myth: Claims that CalCards are legally required usually come from scheme guidance, not law.
Who genuinely benefits from owning a CalCard, and who can safely do without one?
Most benefit:
- Electricians carrying out frequent EICRs or periodic inspections
- NVQ learners developing competence under EAS 2024
- Contractors with multiple testers or high audit exposure
- Commercial electricians where results may be scrutinised
Can often do without one:
- Low-volume domestic installers
- Electricians relying on annual calibration and built-in tester self-checks
- Users with documented alternative verification methods
It is not essential for everyone, but it adds professionalism and defensibility where test accuracy is likely to be questioned.
What types of electrical testing does a CalCard not verify, and why does that matter?
A CalCard does not verify:
- Loop impedance
- RCD trip times
- Voltage measurement
- Phase rotation
- Earth electrode resistance
This matters because BS 7671 requires all these parameters to be tested where applicable. Relying solely on a CalCard could miss faults in other tester functions.
Key point: A CalCard is a supplementary check, not a universal validator. Full calibration and other verification methods remain essential for compliance and liability protection.
How do competent person schemes like NICEIC or NAPIT view CalCards during audits?
Schemes such as NICEIC and NAPIT generally view CalCards positively as evidence of good practice.
Auditors may:
- Accept CalCard records as proof of interim verification
- Expect them alongside, not instead of, calibration certificates
- Value documented checks after drops or damage
Lack of a CalCard is not usually penalised if alternative verification is documented, but using one strengthens professional defensibility.
Myth clarification: CalCards are recommended, not mandated, by schemes.
How often should a CalCard be used in real-world electrical testing work?
There is no fixed interval in BS 7671. In practice:
- Monthly or before major jobs is common
- Weekly for high-volume EICR work
- Quarterly for occasional testers
Use it after storage, transport, or potential damage. Always log results. Overuse can cause wear, so apply a risk-based approach suited to your workload.
Can a CalCard help protect you if test results are questioned months or years later?
Yes, to a degree.
Documented CalCard checks provide evidence that the tester was functioning correctly at the time of testing, supporting due diligence under EAWR 1989 and BS 7671. This can be valuable in disputes, insurance claims, or investigations.
However, it is not a complete safeguard. Calibration records, correct procedures, and full documentation remain essential.
Are modern multifunction testers with built-in self-checks reducing the need for CalCards?
Modern testers with internal diagnostics do reduce reliance on CalCards for basic verification. These self-checks often satisfy EAWR expectations for maintained equipment.
However, they may not replicate real resistance loads. CalCards provide independent verification, which is still valued during audits, especially where results are high-risk or contentious.
For many users, CalCards are now supplementary rather than essential.
How should an electrician decide whether the £20–£30 cost of a CalCard is worthwhile?
Consider:
- How often you test
- Whether your work is audited or scrutinised
- The risk of results being challenged later
- Whether you already use reliable self-checks
For frequent inspectors, NVQ learners, or scheme members, the cost is usually justified. For occasional domestic work, it may be unnecessary.
Decision rule: If documented verification strengthens your professional position without duplication, it’s worth it. If not, prioritise calibration and core test equipment first.
