Guide · checked October 2026
Diagnostic reference levels in the cath lab
UKHSA's national diagnostic reference levels (December 2025) include no value for coronary angiography or PCI, so cath labs rely on local DRLs set from their own dose surveys; the only cardiac device procedure listed is a permanent single or dual chamber pacemaker, at 1.7 Gy·cm² dose-area product per exam.
What the national table includes
UKHSA's National Diagnostic Reference Levels from 11 December 2025 give interventional values as dose-area product per exam in Gy·cm². Table 7, interventional procedures on adult patients, lists a permanent pacemaker (single or dual chamber) at 1.7 Gy·cm², adopted in 2025. We found no national value for coronary angiography, PCI or other cath lab procedures, and the table gives no fluoroscopy times.
UKHSA describes national DRLs as the starting point for optimisation when employers set local DRLs.
The legal duty
IR(ME)R 2017 regulation 6(5)(c) requires the employer to establish DRLs, regularly review them and make them available to operators. For interventional radiology, DRLs are required where appropriate, and for other exposures the employer must have regard to national and international DRLs and local dose surveys. Regulation 6(7) requires a review whenever DRLs are consistently exceeded, with corrective action where appropriate.
Setting local DRLs
Work with your Medical Physics Expert. Group procedures so that like is compared with like (diagnostic angiography separately from PCI, for example), collect dose-area product from a representative period, and set and review the local level from that survey. Record where the data came from so the next survey is comparable.
What a DRL is not
- Not a dose limit for an individual patient.
- Not a target to stay just under.
- Not proof of optimisation by itself.
Where Cath Copilot fits
Cath Copilot records the reconciled dose-area product and fluoroscopy time for every case, which gives a cleaner base for a local dose survey. A site setting defines the local notification level, and a rule flags cases above it for a named person to own and close. The prototype's level is illustrative; your Medical Physics Expert sets the real one.
Cath Copilot is a prototype on synthetic data only. It is not a medical device and is not for clinical use.
Questions
Is there a national DRL for PCI?
Not in UKHSA's December 2025 table, which we checked. Cath labs set local DRLs from their own dose surveys.
What is the national DRL for a pacemaker?
UKHSA lists 1.7 Gy·cm² dose-area product per exam for a permanent single or dual chamber pacemaker, adopted in 2025.
Sources
Official pages, checked October 2026. Guidance changes, so check the current version before you rely on it.
General information for healthcare managers and clinical teams, checked October 2026. It is not legal, regulatory or clinical advice; follow the current official guidance and your organisation's own policies. No patient data is used in these examples. Cath Copilot is a prototype running on synthetic data only. It is not a medical device and is not for clinical use. It recommends, drafts, and routes; it never diagnoses, orders, or decides. A clinical safety and information-governance process precedes any use with real patient data.