Medical imaging monitor rules and regulations in New Zealand

Who actually sets the rules

New Zealand has no single statute that tells you how bright a radiology reporting monitor must be. The rules that matter come from three separate places and stack on top of each other: a professional standard that supplies the numbers, an accreditation code that makes those numbers auditable, and a radiation safety code that treats displays as equipment inside a quality assurance programme. A fourth, Medsafe device notification, is frequently misunderstood and does less than people assume.

Understanding which instrument does what matters, because it tells you who will ask you for evidence and what evidence will satisfy them.

Instrument	What it is	Legal status in New Zealand	What it says about monitors
RANZCR Standards of Practice for Clinical Radiology v12.0	Professional standard from the Royal Australian and New Zealand College of Radiologists, approved 7 November 2025	Professional standard, not legislation. Becomes auditable via IANZ accreditation	Supplies the actual specification numbers and the quality assurance cadence
New Zealand Code of Radiology Management Practice (NZCRMP)	The accreditation standard IANZ assesses imaging services against, developed from ISO 15189	Accreditation requirement, not legislation	Counts monitors and workstations as radiology equipment, so they inherit equipment record, calibration and labelling duties
Code of Practice for Diagnostic and Interventional Radiology (ORS C1)	Issued by the Director for Radiation Safety under section 86 of the Radiation Safety Act 2016, in force 1 December 2024	Legally binding on the holder of a source licence	Classifies digital image displays as ancillary equipment that must be tested within the quality assurance programme
Medsafe WAND	Web Assisted Notification of Devices, a Medsafe notification database	Statutory notification duty on the device sponsor	Records that a device was notified. Sets no performance requirement

RANZCR v12.0 states the relationship directly: in New Zealand, International Accreditation New Zealand administers a radiology practice accreditation programme underpinned by the New Zealand Code of Radiology Management Practice, which references the Standards. So the professional numbers and the accreditation audit are joined, and that join is where most New Zealand practices meet these requirements in real life.

The current monitor specification numbers

These are the figures from the Monitor Specification Table in the addendum to the RANZCR Standards of Practice for Clinical Radiology v12.0, approved 7 November 2025.

Parameter	CR/DR	CT	Mammography	MRI
Matrix size	at least 3 MP	at least 3 MP	at least 4.2 MP per image at full resolution, maximum pixel pitch 0.2 mm	at least 3 MP
Luminance	at least 350 cd/m2	at least 350 cd/m2	at least 450 cd/m2	at least 350 cd/m2
Luminance ratio (Lmax/Lmin)	at least 250	at least 250	at least 250 (350 preferable)	at least 250
Bit depth	at least 8 bits	at least 8 bits	at least 8 bits	at least 8 bits
Luminance uniformity	within 30%	within 30%	within 30%	within 30%
Calibration	GSDF within 10%	GSDF within 10%	GSDF within 10%	GSDF within 10%
Lmin	at least 1 cd/m2	at least 1 cd/m2	at least 1 cd/m2	at least 1 cd/m2

Luminance uniformity is calculated as (Lmax minus Lmin) divided by Lcentre, and v12.0 adds that within 15 percent is ideal. The table cites Australian Technical Specification ATS 5816:2013 for CR/DR, CT and MRI, and AAPM Report No. 270, Display Quality Assurance (2019), for mammography.

One wording note worth knowing if you are comparing sources. Version 11 labelled the 350 cd/m2 row “Max luminance”; version 12.0 labels the same row “Min luminance” while separately retaining an “Lmin at least 1 cd/m2” row. Read in engineering terms, the requirement is unchanged: the display’s maximum achievable luminance must reach at least 350 cd/m2 (450 for mammography), while its black level (Lmin) must sit at or above 1 cd/m2. If a vendor quotes you a 350 cd/m2 panel, confirm that figure is sustained calibrated luminance rather than a peak specification, because a panel that only touches 350 cd/m2 uncalibrated will fall below it once calibrated and as the backlight ages.

What changed between version 11 and version 12

This matters because a lot of published guidance about New Zealand and Australian display requirements still quotes version 11, and two of its most repeated numbers are no longer in the standard.

Version 11 contained an explicit specification for secondary (review) monitors: maximum luminance of at least 250 cd/m2, GSDF accuracy within 20 percent, and Lmin of at least 1 cd/m2. It also recommended ambient lighting of 20 to 40 lux in reading areas, and suggested considering an anti reflective coating on monitor screens.

Version 12.0 does not carry those figures. RANZCR restructured the standard to fold modality standards into the general standards and to remove specificity that dates quickly. The obligations did not disappear, they moved up a level of abstraction: R3.14 requires that diagnostic imaging monitors and associated software ensure display quality allows accurate representation of images and interpretation of each study, and the environment requirements still call for attention to light reflection on monitors and workstations that meet ergonomic requirements.

The practical consequence for a New Zealand practice is that you can no longer point at a published lux figure and call the room compliant. You have to be able to show that your reading conditions support accurate interpretation, which in practice means documenting your own reading room light levels and holding them steady rather than inheriting a number from a superseded edition. Keep measuring at 20 to 40 lux if that is what your rooms were designed around, but record it as your controlled parameter rather than as a quoted requirement.

Quality assurance: what you have to do and record

The specification numbers are the easy half. Accreditation turns on whether you can evidence the programme around them. RANZCR v12.0 sets out the following.

• Monthly TG18 testing as a floor. Monitor quality assurance testing comprises at minimum monthly TG18 test patterns. The standard cites AAPM Report No. 270 and the EUREF monitor QC test patterns as the reference sources.
• Documented and retained conformance tests. Conformance tests of display systems are documented and retained for ongoing quality assurance.
• A planned quality assurance programme (R3.17) covering equipment testing against required specifications including checks as part of annual maintenance, digital imaging and teleradiology services including acquisition, compression, transmission, archiving, retrieval, backup and recovery, review of diagnostic image quality by the practitioners who report on images, and monitoring of any AI tools and their software updates.
• Trendable records (R3.18). Measurements and other results from quality assurance activities are recorded so that trends are detectable. A pass or fail flag alone does not satisfy this, because a display drifting steadily toward its limit is exactly the signal you are meant to catch.
• Records for the lifetime of the equipment (R3.19). All maintenance and testing records must be kept for at least the lifetime of the equipment and be accessible to the site where the equipment is used.
• A documented programme specification. A systematic approach for all equipment tests specifying frequency, tolerances, recording requirements and the personnel responsible, a documented audit plan, records for every test undertaken, and a protocol for managing test failures and non compliances that includes action levels, reporting requirements and timely action.

That last point is where programmes usually fail an assessment. Practices can often produce test results. Fewer can produce the document that says who owns the testing, what the tolerance is, and what happens when a display fails.

What IANZ assessors look for

The New Zealand Code of Radiology Management Practice contains one definitional sentence that does most of the work. In its clause 5.3 note on radiology equipment, it states that ancillary equipment including imaging equipment, computers, monitors and workstations are included as radiology equipment, as applicable.

Once a monitor is radiology equipment, the rest of clause 5.3 applies to it:

• Capability on installation and in routine use (5.3.2). Equipment shall be shown, upon installation and in routine use, to be capable of achieving the performance required, and management shall establish a programme that regularly monitors and demonstrates proper calibration and function, plus a documented and recorded preventive maintenance programme that at minimum follows the manufacturer’s recommendations.
• Unique identification (5.3.3). Each item of equipment shall be uniquely labelled, marked or otherwise identified. Every reporting display needs an asset identity, not just a desk location.
• Equipment records (5.3.4). Records shall include the identity of the equipment, manufacturer, model and serial number, dates of receipt and entry into service, current location, condition when received, manufacturer’s instructions, performance records confirming suitability for use, maintenance carried out and planned, any damage, malfunction, modification or repair, and the predicted replacement date. Performance records should include calibration reports with dates, results, adjustments, acceptance criteria and the due date of the next calibration.
• Calibration status labelling (5.3.9). Where practicable, equipment requiring calibration shall be labelled or coded to show calibration status and the date recalibration is due.
• Look back on defect (5.3.7). When equipment is found defective it shall be taken out of service, labelled and stored until repaired and shown to meet acceptance criteria, and the service shall examine the effect of the defect on previous examinations. For a display this is the clause with teeth: a monitor found badly out of calibration raises a question about the studies already reported on it.
• Return to service after repair (5.3.10). Equipment removed from the radiology service’s direct control, or repaired or serviced, shall be checked and shown to be functioning satisfactorily before being returned to use.
• Environment (5.2.4 and 5.2.5). The environment shall not invalidate results or adversely affect examination quality, explicitly including lighting, and the service shall monitor, control and record environmental conditions where they may influence quality.

An edition note. The code IANZ currently publishes is the second edition, July 2020, which rebranded and reformatted the April 2011 first edition with editorial changes only and no material change to accreditation requirements. RANZCR v12.0 refers to a 2024 edition of the code. Confirm with IANZ which edition your next assessment will run against before you map your programme to clause numbers.

Where ORS C1 and the Radiation Safety Act fit

The Code of Practice for Diagnostic and Interventional Radiology (ORS C1) is the one genuinely legislative instrument in this stack. It is issued by the Director for Radiation Safety under section 86 of the Radiation Safety Act 2016, came into force on 1 December 2024, and replaced the 2018 code.

It sets no display specification, and it is worth being clear about that, because it is easy to assume a radiation safety code governs image quality. It does not. What it does is pull displays into the licence holder’s obligations by definition. ORS C1 defines ancillary equipment as equipment other than radiological or protective equipment that has an impact on the performance of a radiological procedure, giving digital image displays as one of its examples alongside image receptors and view boxes.

From there, two obligations reach your monitors:

• Clause 6(a). The holder of a source licence must provide, maintain, test and service radiological, protective and ancillary equipment so that it is appropriate for the procedures performed and remains capable of fulfilling its design requirements for protection and safety throughout its operational lifetime.
• Clause 20(a). The comprehensive quality assurance programme for medical exposures must measure and assess physical parameters at commissioning before clinical use, periodically after commissioning, after any major maintenance that could affect protection and safety, and after installing any new software or modifying existing software that could affect protection and safety. It must include performing tests on ancillary equipment, and must set baselines. Under clause 20(b), the methods and values used for baselines and for remedial and suspension levels must be reviewed and approved by a medical physicist expert. Clause 21 requires regular internal or external independent audits of the programme.

The software clause is the one that catches IT teams. A graphics driver update, a PACS client upgrade, a change to the display’s colour management, or a Windows feature update that resets a display profile are all software changes to the imaging chain. If a change could affect the display’s calibrated behaviour, the sensible reading is that it triggers a retest rather than a shrug. Building that trigger into change management is straightforward, and it is far cheaper than discovering at audit that a fleet wide driver rollout silently invalidated a year of calibration records. This is where display QA stops being a hardware topic and becomes a PACS and RIS and endpoint management topic.

Medsafe, WAND, and what device notification does not mean

Medsafe operates the Web Assisted Notification of Devices database. A New Zealand based sponsor must be appointed for devices supplied here, and the sponsor is responsible for listing the device in WAND within 30 days of being retained, before supply, unless exempt.

The important part is what WAND is not. There is no approval and no licence associated with a WAND notification, and no fee. WAND functions as a database so that Medsafe can monitor device safety and notify sponsors of recalls. Access to the database is restricted to sponsors.

So a WAND entry tells you a sponsor exists and a notification was made. It tells you nothing about luminance, resolution, GSDF conformance or suitability for primary reporting. When a supplier offers a WAND listing as evidence that a display is compliant for diagnostic use in New Zealand, that is a category error. Ask instead for the calibrated performance figures against the Monitor Specification Table, and for the display’s quality assurance tooling.

Common misconceptions

“There is a New Zealand regulation requiring 350 cd/m2.” There is not. The 350 cd/m2 figure is from the RANZCR professional standard, and it reaches New Zealand practices through IANZ accreditation rather than through legislation. The distinction matters when you are writing policy documents that cite their own authority.

“RANZCR requires reading rooms at 20 to 40 lux.” That recommendation was in version 11 and is not carried into version 12.0. Control and record your ambient light, but do not cite a withdrawn figure as a current requirement.

“Review monitors must be at least 250 cd/m2.” Also a version 11 figure that version 12.0 does not carry. The current standard distinguishes displays by whether they support accurate interpretation of each study rather than by a published secondary tier number.

“The monitor is a clinical asset, so IT is not involved.” Under the New Zealand Code of Radiology Management Practice the monitor is radiology equipment alongside the computers and workstations driving it, and under ORS C1 a software change that could affect performance is a retest trigger. The graphics pipeline, driver baseline, and change control sit with IT. So does the evidence trail.

“Our displays self calibrate, so we are covered.” Integrated front sensors and vendor QA software satisfy the measurement, not the programme. You still need the documented test frequencies and tolerances, the named owner, the failure protocol with action levels, records that make trends detectable, and retention for the lifetime of the equipment.

A practical compliance checklist

1. Inventory every display that touches an image, and classify each one as primary reporting or review. Record make, model, serial number, install date, location and predicted replacement date, which is what clause 5.3.4 asks for.
2. Check each primary display against the Monitor Specification Table for the modalities actually reported on it. Confirm sustained calibrated luminance, not peak specification.
3. Write the programme document, not just the results. Test types, frequencies, tolerances, who performs them, and what happens on failure including action levels and escalation.
4. Set the monthly TG18 test pattern check as your floor and record each run against the display’s asset identity.
5. Make QA records trendable. Store the measured values over time, not just a pass flag, so drift is visible before it becomes a failure.
6. Label calibration status and next due date on or against each display, per clause 5.3.9.
7. Add a display retest trigger to IT change management for graphics driver updates, PACS client upgrades, display firmware, and operating system changes that could affect the imaging chain.
8. Define the failure response, including the look back question clause 5.3.7 implies: if this display was out of specification, which reported studies were affected?
9. Retain records for the lifetime of the equipment and keep them accessible at the site where the display is used.
10. Confirm the edition of both the RANZCR Standards and the New Zealand Code of Radiology Management Practice that your next IANZ assessment will use, before mapping your documentation to clause numbers.

Trucell works on this with imaging practices as an IT problem rather than a purchasing one: display specification and supply through our medical displays solution, the graphics and workstation pipeline that actually drives the panel at full bit depth, the change control that keeps calibration intact, and the record keeping that turns a fleet into evidence. If you are preparing for an IANZ assessment or standing up a display QA programme, our radiology IT support team can help you build the programme document and the evidence trail alongside the hardware. For the underlying concepts in plain language, see our companion guide to diagnostic display QA for radiology.

Sources

• RANZCR Standards of Practice for Clinical Radiology, Version 12.0, approved by the Faculty of Clinical Radiology Council on 7 November 2025. Contains the New Zealand accreditation statement, requirements R3.14 and R3.17 to R3.19, the evidence items on monthly TG18 testing and documented QA programmes, and the Monitor Specification Table addendum.
• New Zealand Code of Radiology Management Practice (NZCRMP), International Accreditation New Zealand, second edition July 2020, developed from ISO 15189:2007. Clause 5.2 on accommodation and environmental conditions, and clause 5.3 on radiology equipment.
• Code of Practice for Diagnostic and Interventional Radiology: ORS C1, issued by the Director for Radiation Safety under section 86 of the Radiation Safety Act 2016, in force 1 December 2024. Definition of ancillary equipment, clause 6 on equipment, clauses 20 and 21 on quality assurance.
• Medsafe, Web Assisted Notification of Devices (WAND), guidance on the database, sponsor obligations and the 30 day notification window.
• AAPM Report No. 270, Display Quality Assurance (2019), and Australian Technical Specification ATS 5816:2013, both cited by the RANZCR Monitor Specification Table.

A note on scope

This guide is general information about the New Zealand regulatory and accreditation landscape for diagnostic display monitors. It is not compliance, accreditation, legal or medical physics advice. Standards and codes are revised: RANZCR v12.0 replaced v11.2 in November 2025 and changed which figures the standard carries, and the edition of the New Zealand Code of Radiology Management Practice that applies to your assessment should be confirmed with IANZ. Where a specific threshold, test frequency or clause number matters, confirm it against the current edition of the source document and with your accreditation body, your radiation safety officer, or a qualified medical physicist before relying on it.