DOSR Updates Military Laser and Radiofrequency Directed Energy Weapons Safety Framework

The Defence Ordnance, Munitions and Explosives Safety Regulator (DOSR) issued two regulatory notices in late March 2026 — amending the DSA 02.OME Part 5 military laser safety regulations and opening consultation on JSP 390, while simultaneously publishing a new compliance guide for radiofrequency directed energy weapons. WOME practitioners operating with laser systems or emerging directed energy capabilities have mandatory review obligations.

DSA 02.OME Part 5 Amendment and JSP 390 Consultation

On 27 March 2026, DOSR published Regulatory Notice RN 2026-04, notifying defence stakeholders of an amendment to Part 5 of the Defence Safety Authority (DSA) 02.OME regulations. DSA 02.OME is the primary regulatory instrument governing ordnance, munitions and explosives (OME) acquisition and in-service safety management across the UK defence enterprise. Its five parts span OME acquisition (Part 1), in-service and operational safety management (Part 2), ranges (Part 3), Major Accident Control Regulations (Part 4), and military laser safety (Part 5).

Part 5 of DSA 02.OME covers the safe handling, operational management, and regulatory obligations associated with military laser systems used across research and development, procurement, training, and maintenance activities both within the UK and on overseas operations. The amendment notified in RN 2026-04 represents a formal update to this technical regulatory framework. Practitioners working with Class 3B and Class 4 laser systems — including target designators, range-finders, training devices, and directed energy test platforms — are specifically within scope.

In parallel, RN 2026-04 opens a formal consultation on Joint Service Publication (JSP) 390 — the original military laser safety publication that predates the current DSA framework. JSP 390 was withdrawn as a standalone publication when laser safety obligations were absorbed into DSA 03.OME and subsequently DSA 02.OME Part 5. The renewed consultation signals that DOSR may be revisiting the scope or structure of this legacy framework, potentially issuing a revised or reconstituted JSP 390 alongside the DSA 02.OME amendments. Stakeholders are encouraged to submit responses to the consultation via DOSR’s official contact channel.

The procedural significance of the DSA 02.OME Part 5 amendment is considerable. Under the UK defence regulatory system, DOSR operates as the independent safety regulator for OME activities, with regulatory notices constituting formal notifications that generate compliance obligations across the defence enterprise. Duty-holders — including Prime Contractors, Design Authorities, Integrated Project Teams (IPTs), and safety case owners — must assess the impact of the amendment on existing safety cases and, where necessary, update their documentation within the timeframes specified in the notice itself.

Radiofrequency Directed Energy Weapons: New Compliance Obligations

Three days after RN 2026-04, DOSR published Regulatory Notice RN 2026-05 — a dedicated Radiofrequency Directed Energy Weapons (RF DEW) Compliance Guide. This is a substantively new regulatory product, reflecting the maturation of RF DEW as an operational capability class within the UK Armed Forces. High-power microwave (HPM) systems, active denial technology, and counter-uncrewed aerial system (C-UAS) RF weapons are all within scope of this category.

The RF DEW compliance guide addresses a gap that has existed in the DSA 02.OME framework since directed energy weapons were first scoped into the regulations. While Class 3B and 4 laser weapons have been regulated under Part 5, radiofrequency emitters operating at high power levels — capable of causing interference to electronic systems, physiological effects on personnel, and incidental ignition of electroexplosive devices (EEDs) — lacked a dedicated compliance pathway. RN 2026-05 addresses this directly.

The intersection of RF DEW and WOME safety is particularly acute. High-power radiofrequency fields present a non-trivial electroexplosive device (EED) initiation hazard. RF DEW test and evaluation environments, forward operating bases where RF systems are deployed alongside ammunition storage facilities, and ship-board environments with co-located weapons and magazine spaces all require careful separation and electromagnetic compatibility (EMC) analysis. DOSR’s compliance guide is expected to require RF hazard assessments — consistent with RADHAZ (Radiation Hazard) principles — to be integrated into safety cases wherever RF DEW and OME are operated in proximity.

The notice is ten pages — a relatively concise format indicating it is intended as a practical compliance aide rather than a comprehensive technical standard. The detailed technical parameters governing RF field strength thresholds, separation distances from EED storage, and personnel exposure limits will be found within the supporting DSA 02.OME framework and relevant NATO guidance. WOME practitioners with responsibilities for weapons integration, range safety, or EED management in RF-rich environments should download and review the guide immediately upon its availability on GOV.UK.

Regulatory Trajectory: DEW Integration into the WOME Framework

The co-publication of RN 2026-04 and RN 2026-05 within three days is not coincidental. It reflects a deliberate regulatory initiative by DOSR to update and expand the DSA 02.OME framework to encompass the full spectrum of directed energy threats and capabilities — both laser and radiofrequency. This is consistent with the UK’s strategic investment in directed energy weapons under the Defence Equipment Plan and the Strategic Defence Review (SDR), which committed to accelerated procurement of DE systems including DragonFire and counter-UAS HPM platforms.

The SDR’s emphasis on directed energy as a cost-effective supplement to kinetic munitions — particularly for high-volume C-UAS engagements — creates a predictable regulatory demand signal. As DE systems move from experimental platforms to operational capability, the volume of safety cases requiring DOSR review and formal regulatory approval will increase substantially. Organisations involved in the DE supply chain — weapon system integrators, platform designers, test facility operators, and IPTs — should expect continued regulatory evolution in this space throughout 2026 and 2027.

For WOME practitioners, the broader implication is that competence in directed energy weapons safety — once a niche specialism confined to research establishments — is becoming a mainstream WOME practice requirement. The Institution of Explosive Engineers (IExpE) and Defence Academy of the United Kingdom have recognised this trend, with Ordnance, Munitions and Explosives (OME) training curricula incorporating directed energy hazard awareness modules.