Gas Detector, Gas Monitor & GDU Calibration Services

A bump test checks the sensor’s response to gas. A calibration adjusts the sensor’s accuracy using certified gases – and produces traceable results. Both are essential for maintaining compliance, but only calibration proves the detector’s accuracy for audit and insurance purposes.

We calibrate for common industrial gases including O₂, CO, H₂S, and LEL (flammable gases), using manufacturer-specified test concentrations. Multi-gas detectors are adjusted and verified against all active sensors. We can also handle specialist mixes (e.g. NO₂, SO₂, VOCs) used in industrial and environmental applications.

Yes. Every calibration includes a digital certificate with test results, gas types used, engineer ID, calibration date, next due date and traceability to national standards. These records are suitable for audits, insurance checks, confined space permits and internal compliance files.

Yes. We regularly calibrate multiple gas monitors and GDUs during a single visit.

This is ideal for sites with several detectors, safety managers overseeing multiple teams, or organisations managing equipment across different departments.

We’ll plan the visit to minimise downtime and can combine calibration with other compliance services where required.

Yes. We offer fully mobile GDU calibration across the UK. We’ll come to your site, minimise disruption, and handle everything on the day – certificates included.

Workshop turnarounds typically take 2–5 working days. For urgent jobs, we offer fast-track options and on-site visits. Fast track we aim to turn around within 24 hours.

We regularly calibrate MSA, Dräger, BW Honeywell (including Microclip units), Crowcon, MultiRAE and more. If your model isn’t listed, just ask – we can usually accommodate it or suggest a suitable alternative.

We inspect the unit, apply a known concentration of test gas, check the sensor response, adjust the readings where required and verify stability before issuing certification. If the detector needs a sensor, filter or repair, we’ll quote before carrying out any additional work.

Absolutely. Every calibration includes a digital certificate showing test results, gas types used, engineer ID, and compliance to relevant standards – perfect for audits.

Yes – we track your equipment’s due dates and notify you ahead of time, so you don’t fall out of compliance or scramble for paperwork.

We’ll flag any issues during inspection and send you a no-obligation quote. We don’t replace parts without permission – no hidden charges, no surprises.

Fixed gas detection systems require full functional verification and flow-rate checks as part of calibration. We test alarm setpoints, check response times, and ensure your system communicates correctly with control panels or alarm beacons.

Yes – that’s our bread and butter. We work with contractors, engineers and health and safety leads managing high-risk sites every day. Your compliance is in safe hands. All testing complies with HSE guidance and manufacturer limits, ensuring your monitors meet entry-permit requirements.

Yes – Velocity Safety provides Gas Detection Unit calibration across the North West, including Blackburn, Preston, Bolton, Manchester, Burnley, and Lancaster. Our engineers offer on-site visits or fast courier turnaround from our Blackburn calibration workshop, with certificates issued the same day where possible

We also support national frameworks and multi-site clients across the UK.

Absolutely. We calibrate Gas Detection Units (GDUs) for teams across the UK – from Leeds and Birmingham to Dundee and Aberdeen. Whether your site is in Yorkshire, Scotland, or the South East, our mobile engineers can attend on-site or handle courier-based calibration through our Blackburn facility.

Yes. Many clients schedule gas monitor calibration alongside Face Fit Testing, LEV Testing or Breathing Air Quality Testing. It’s a simple way to reduce downtime and keep multiple compliance requirements up to date in one visit.