What does IS-35 address?
CSN Instruction IS-35 of 4 December 2013 remains listed in the CSN's current instruction catalogue, checked on 12 October 2026. Its subject is change control, rather than a general manual for designing radioactive transport packages.
A certificate of Spanish origin means approval of a package design whose country of origin is Spain. IS-35 also addresses physical or operational changes made by a consignor to packaging it uses, including packages without a design approval certificate.
Changes to a design with Spanish-origin approval
The applicant first assesses whether a proposed change affects nuclear safety or radiation protection. A safety-related change requires a safety evaluation. If the approval's underlying criteria, standards or conditions change, the revised approval certificate must be issued before the modification takes effect.
Changes that do not require certificate revision still have reporting and document-update duties. Read sections 3 and 4 of IS-35 for the appropriate category and timetable. Calling a change minor does not replace the documented assessment.
Changes made by the consignor
Section 5 covers consignor changes to packaging with or without an approval certificate. Where a change alters the relevant compliance basis, the revised certificate or supporting compliance documentation must be available before implementation, as applicable. The safety evaluation's results require the package designer's documented acceptance.
The distinction matters when packaging is owned or hired: possession of equipment does not itself establish permission to change its approved configuration or operating conditions.
Use today's approval framework
The 2013 instruction cites the former nuclear and radioactive installations regulation. Royal Decree 1217/2024 replaced that regulation and redirects references to the corresponding provisions of the new text.
Its Article 109 governs package-design approvals or validations and transport authorisations required by the dangerous goods rules, with a prior CSN report. The current MITECO transport authorisation procedure explains where to submit the relevant request and supporting evidence. Assess whether approval is required under the applicable transport rules; the existence of IS-35 does not mean every package needs an approval certificate.
Prepare a clear change review file
As a practical starting point, identify the package, design revision, certificate if applicable, permitted contents and the proposed change. Gather the relevant drawings, operating and maintenance documents, previous assessments and the designer's response. Keep versions distinguishable so a reviewer can see which documents describe the equipment actually used.
Describe the reason for the change and the transport modes involved. Resolve missing evidence with the designer and the organisations responsible for approval or compliance before arranging implementation. DGSA advisory services can help review the transport requirements and documentation. Contact DGSA with the package details and proposed change to discuss the appropriate review.