An ECG test has two halves, because “safe” and “accurate” are different questions.

Electrical safety. An ECG connects directly to the patient through electrodes, which makes its leads applied parts — and that raises the stakes on leakage current. A tiny current that would be harmless through the skin can be dangerous on a direct path toward the heart. So we measure protective earth resistance, insulation resistance, and the leakage currents through those patient connections, against the limits for a patient-connected device.

Performance and calibration. Using a calibrated ECG simulator that feeds the machine known signals, we verify the trace comes back right:

• Calibration signal — a 1 mV input should produce exactly 10 mm of deflection.
• Paper speed / timebase — the standard 25 mm/s (and 50 mm/s where used) is accurate, so intervals measure true.
• Gain / sensitivity across each lead.
• Heart-rate accuracy against known simulated rates.
• Frequency response and filtering, so the trace is clean without distorting the signal.

A miscalibrated ECG doesn’t announce itself. The machine still switches on, still prints a trace, still looks fine. But if the gain has drifted, low-voltage complexes can read as normal, or normal ones can look like hypertrophy. If the paper speed is off, every interval you measure — PR, QRS, QT — is wrong by the same margin. A clinician makes a real decision on that trace. Calibration is what lets them trust it.

ECG machines are medical electrical equipment, so they’re tested and managed under AS/NZS 3551, not the general appliance standard. That means a biomedical technician with calibrated test equipment — an electrician tagging your power boards to AS/NZS 3760 isn’t testing your ECG, and shouldn’t be.

Under AS/NZS 3551 the interval is risk-based, set by the device’s criticality and the manufacturer’s guidance. For most practices an ECG lands on a regular annual test and calibration cycle, and it should also be checked after any repair or if the trace ever looks wrong. We set the interval, track it, and remind you before it’s due.

What you’ll find in our report:

• The ECG identified by make, model and serial number on your asset register
• Electrical safety results — earth resistance, insulation, patient leakage
• Performance results — calibration, paper speed, gain, heart-rate accuracy
• Pass/fail with the next due date
• A calibration record you can produce for accreditation

How the testing process works

1. We come to you — no shipping the ECG away.
2. Safety and performance checks — both halves, in one pass, with calibrated test gear.
3. Result on the day — if it fails, you know immediately, with a clear next step.
4. Logged and tracked — results into your register, reminder set for next time.

Done alongside the rest of your AS/NZS 3551 testing, so your whole fleet is covered in one visit.

Tell us what you run and where you are. We’ll test and calibrate your ECG onsite to AS/NZS 3551 — safety and performance — and keep it on schedule from here.