SIST EN 1992-1-2:2023/oprA1:2026

SIST EN 1992-1-2:2023/oprA1:2026 is a CEN draft amendment to Eurocode 2, Part 1-2, for the structural fire design of concrete structures. It is intended for use with the Eurocode basis of design and the fire actions part of EN 1991, and it updates references, definitions, design rules, and annex material for fire-exposed concrete members.

What does SIST EN 1992-1-2:2023/oprA1:2026 specify?

SIST EN 1992-1-2:2023/oprA1:2026 specifies amendments to the European Standard for structural fire design of concrete structures. The scope remains focused on the accidental situation of fire exposure, covering structures that must maintain a loadbearing function, a separating function, or both.

The document applies to structures within the scope of EN 1992-1-1 and to normal weight concrete up to strength class C100/115 and lightweight concrete up to LC50/60. It is organized as amendments to the title, references, introduction, scope, normative references, terms, basis of design, tabulated design data, simplified design methods, advanced design methods, and annexes A, D and E.

What are the key requirements of SIST EN 1992-1-2:2023/oprA1:2026?

SIST EN 1992-1-2:2023/oprA1:2026 mainly updates how fire design is linked to other Eurocodes and clarifies how the design methods are to be used in practice. The most important points are the revised references, the clarified assumptions, and the tightened limits on tabulated and simplified methods.

Updated links to other Eurocodes

Clause 1 and Clause 2 are amended so the document is used with EN 1990-1, EN 1991 (all parts), EN 1991-1-2:2024, EN 1991-1-7:2025, and EN 1992-1-1. In practice, this means the fire design rules are not standalone - the designer must take actions, basis of design, and the normal-temperature member design from the connected Eurocode parts.

Assumptions for the design fire and fire protection

Clause 1.2 keeps two core assumptions: the relevant design fire scenario is chosen by qualified and experienced personnel or by national regulation, and any fire protection measure used in the design is maintained adequately. That matters because the fire design is only as valid as the fire scenario and the reliability of the protection measures assumed in the calculation.

Basis of design for fire exposure

Clause 4 clarifies that the design must address not only loadbearing failure but also integrity and insulation failure. It also states that non-loadbearing elements are expected to keep loadbearing function under self-weight so that they can still perform their separating function.

Clause 4.7 updates the recommended factor for the fire design situation when the fire action is obtained from EN 1991-1-2:2024. The note gives the recommended values of ηfi, with a different value for imposed loads in category E unless the National Annex sets another value. For practice, this affects the design fire load level used in the fire combination.

Tabulated design data

Clause 6 limits tabulated design data to member analysis according to 4.7 and to standard fire exposure only, without extrapolation outside the stated application range. The clause also states that these data may come from tests, calculation models, or both, and that they give safe-sided results. In practice, a designer can use tables for a recognized solution, but only within the exact member type and scope covered by the tables.

Simplified design methods

Clause 7 says simplified design methods also refer to member analysis according to 4.7 and must not be extrapolated beyond their range of application. The clause explains that these methods rely on global equilibrium equations and produce a single design result such as a section temperature or a member fire resistance. In practice, they are intended for fast design checks, but only where the method assumptions fit the member being designed.

Advanced design methods

Clause 8 requires advanced design methods to be validated against relevant test results and checked by sensitivity analysis of critical parameters. This means more sophisticated calculations must still be anchored in test evidence and engineering judgement, especially for buckling length, element size, and load level.

Annex-specific changes

Annex A updates references for lightweight aggregate concrete structures. Annex D revises the definition of the modified mechanical reinforcement degree, ωmod, for columns under fire conditions. Annex E updates a complementary table parameter for load-bearing solid walls.

What terms does SIST EN 1992-1-2:2023/oprA1:2026 define?

• Design fire scenario - The fire exposure case chosen for design, either by qualified and experienced personnel or by national regulation.
• Loadbearing function - The ability of a concrete structure or member to carry load under fire exposure.
• Separating function - The ability of a member to separate fire-exposed spaces during the fire situation.
• National Annex - The national document that may set nationally determined parameters where the Eurocode allows national choice.
• NDP - Nationally determined parameters used where the Eurocode leaves values to national selection.
• Tabulated design data - Design data given in table or equation form, derived from tests, models, or both, and used for recognized fire design solutions.
• Simplified design methods - Methods based on global equilibrium equations that produce one design quantity for a section or member.
• Advanced design methods - More detailed calculation methods that must be validated by test evidence and checked by sensitivity analysis.

Who uses SIST EN 1992-1-2:2023/oprA1:2026?

SIST EN 1992-1-2:2023/oprA1:2026 is used by structural engineers, fire designers, and checkers who design concrete buildings and civil structures for fire exposure. It is also used by authorities and national code bodies that set or review nationally determined parameters through National Annexes.

In practice, it supports the design of members that must keep carrying load, members that must separate compartments, and projects that use tabulated, simplified, or advanced fire design methods. Manufacturers, testing organizations, and consultants may also use it when their fire protection measures or calculation methods are part of the design basis.

What changed in SIST EN 1992-1-2:2023/oprA1:2026 from the previous edition?

SIST EN 1992-1-2:2023/oprA1:2026 amends EN 1992-1-2:2023. The changes listed in the document include updated references to other Eurocodes, revised terms and symbols, clarifications in the basis of design, revised rules for tabulated and simplified methods, updated validation rules for advanced methods, and changes in Annexes A, D, and E.

Which standards are used with SIST EN 1992-1-2:2023/oprA1:2026?

• EN 1990 (all parts) - provides the basis of structural and geotechnical design used with the fire design rules.
• EN 1990-1:2023+A1:2026 - supplies the referenced load-combination and category-related values used in the amendment.
• EN 1991 (all parts) - provides actions on structures used alongside the fire design clauses.
• EN 1991-1-2:2024 - provides the fire actions and related data that feed the design fire situation.
• EN 1991-1-7:2025 - contributes accidental actions where referenced.
• EN 1992-1-1 - provides the normal-temperature concrete design rules used together with this part.
• EN 1993-1-2 - is referenced in the bibliography as a related fire design standard for steel structures.

What does the SIST EN 1992-1-2:2023/oprA1:2026 document contain?

SIST EN 1992-1-2:2023/oprA1:2026 contains editorial and technical amendments to the Eurocode text rather than a full standalone design code. It revises the introduction, scope, normative references, definitions, basis of design, tabulated design data, simplified design methods, and advanced design methods.

The document also revises a formula and multiple figures, including those used for tabulated and simplified design procedures, and it updates references inside the annexes. In practical use, those changes affect how designers select fire scenarios, apply design methods, and read the annex material for lightweight aggregate concrete, column buckling, and load-bearing solid walls.