BP Machine & Sphygmomanometer Calibration
The blood pressure machine is the instrument a practice uses most and checks least. A gauge that reads 8 mmHg low still looks perfectly normal — it just quietly moves patients either side of a treatment threshold. We test it, adjust it and certificate it, usually on site in one visit.
What we calibrate
- Wall-mounted aneroid sphygmomanometers
- Desk and mobile-stand aneroid units
- Handheld aneroid gauges
- Digital and automatic BP machines used in consulting rooms
- Mercury-free clinical BP devices
Multi-parameter patient monitors with an NIBP channel are covered on our patient monitor page.
What the test involves
Every unit is checked against a traceable reference manometer, not against another BP machine:
- Zero — the needle or display rests at zero with no pressure applied
- Pressure accuracy — readings compared with the reference at points across the clinical range
- Leak test — pressure holds in the cuff, tubing and bulb without creeping down
- Deflation valve — releases at a steady, controllable rate so readings can be taken properly
- Cuff, bladder and tubing — checked for perishing, cracks and the right size for your patients
If a reading is outside tolerance we adjust it and test again, and the certificate shows both sets of readings.
Common faults we find
Most BP problems are not the gauge at all. Perished bulbs and hoses leak pressure, valves stick and deflate in jumps, and cuffs are used on arms they are too small for — which reads high on every patient. A gauge that has been dropped will often still move but sit off zero. Worn parts are consumables: we replace them rather than certificate a unit that cannot hold pressure.
What you receive
A calibration certificate per device recording the readings before and after adjustment, the reference equipment used and the next recommended date — formatted for SAHPRA and ISO 13485 audits. If a unit cannot be brought back within tolerance we say so and quote a replacement, rather than issue a certificate it does not deserve.
How often?
Most practices calibrate BP machines annually, and sooner after a drop, a repair or a reading a clinician doubts. Follow the manufacturer's interval where it is shorter. A maintenance contract takes the tracking off your hands.
Book a BP Calibration
Tell us how many units and the type — we will quote the visit.
Need new cuffs or a replacement unit? We supply those too.
Browse All Products →Common questions
BP calibration FAQs
Often you can't — that is the problem. Signs to act on: the needle doesn't rest on zero, pressure creeps down while you hold it, the valve releases in jumps, or readings disagree with another device. If it has been more than a year, or it has been dropped, book a check.
Yes. BP calibration is almost always done on site in one visit, alongside any other equipment that is due. Units that need parts are repaired on the spot where we carry them, or collected and returned.
Inspectors and accreditation bodies expect documented evidence that measuring equipment is accurate. A certificate from a SAHPRA-registered provider (licences 00001974MD and 00002058MD), recording before-and-after readings against a traceable reference, is that evidence.
We focus on clinical devices used in practices and facilities. If you are unsure whether a unit qualifies, send us the make and model and we will tell you honestly.
BP machines due?
One visit, every unit tested and certificated.