Best Office Chairs Europe

EN 1335 vs ANSI/BIFMA X5.1

Many chairs sold in Europe carry the American standard, the European one, or both. They answer different questions.

Updated By The Best Office Chairs Europe editorial team7 sources

EN 1335 tells you whether a chair can be adjusted to fit a range of European bodies (part 1) and whether it is safe and durable (part 2). ANSI/BIFMA X5.1 is a set of mechanical safety and durability tests with no dimensional requirements. A chair can pass BIFMA and still have no EN 1335 Type.

The user weight each standard’s tests are based onEN 1335-2:2018 (Europe · work chairs): 110 kg; ANSI/BIFMA X5.1-2017 (United States · general office): 125 kg; ANSI/BIFMA X5.11-2015 (United States · large occupant): 181 kg.0255075100125150175200EN 1335-2:2018Europe · work chairs110 kgANSI/BIFMA X5.1-2017United States · general office125 kgANSI/BIFMA X5.11-2015United States · large occupant181 kguser weight the test loads are based on, kgTEST BASIS · USER WEIGHT
The occupant weight each standard's test loads are built on.

What is the core difference?

EN 1335-1 sets mandatory dimensions and adjustment ranges by Type, measured with a 64 kg template under ISO 24496. BIFMA X5.1 leaves fit to a separate, voluntary ergonomics guideline, BIFMA G1, which targets the 5th to 95th percentile of the CAESAR body-scan population. For loads, EN 1335-2 is based on a 110 kg user for 8 hours a day, while X5.1-2017 uses a 275 lb (about 125 kg) test user, raised from 253 lb in the 2011 edition. ANSI/BIFMA X5.11 adds tests and a minimum seat width for occupants up to 400 lb (about 181 kg); the test house Micom notes it is not a bariatric standard.

EN 1335 and BIFMA, side by side

EN 1335 vs BIFMA
EN 1335ANSI/BIFMA X5.1
Current editionEN 1335-1:2020 (+A1:2022) (part 1), EN 1335-2:2018 (part 2)ANSI/BIFMA X5.1-2017 (R2022)
Dimensions and adjustabilityMandatory, by Type Ax, A, B or CNone; ergonomics in voluntary G1
User basis for tests110 kg, 8 h a day275 lb (≈125 kg); X5.11: 400 lb (≈181 kg)
Test methodsEN 1728 and EN 1022BIFMA's own methods
Legal status in the EUVoluntary; no CE markingVoluntary; not a European standard
Common proofGS mark, named lab reportLab certificate citing the edition

What does this mean when you buy?

  • If you need to show an employer or procurement team that a chair fits the European framework, ask for the EN 1335-1 Type. BIFMA alone does not give you one.
  • If durability under heavier use matters, a BIFMA certificate is useful evidence on top: its test user is heavier than EN 1335-2's.
  • Don't confuse BIFMA LEVEL with X5.1. LEVEL is a sustainability certification based on ANSI/BIFMA e3, with three tiers.

In our register, 12 chairs declare both EN 1335 and BIFMA (HÅG Capisco 8106, HÅG Futu Mesh 1100, HÅG SoFi Mesh 7500, IKEA JÄRVFJÄLLET, IKEA MARKUS, Interstuhl EVERYis1 (EV216), Interstuhl JOYCEis3 (JC216), Interstuhl PUREis3 (PU213), Vitra AC 5 Work, Vitra ID Mesh, Wilkhahn IN (184/7), Wilkhahn ON (174/7)). 4 declare BIFMA but no EN 1335: Herman Miller Aeron, Herman Miller Cosm, Herman Miller Embody, Herman Miller Sayl.

More: EN 1335 explained · all standards

Sources

  1. Micom Lab: ANSI/BIFMA X5.1-2017: www.micomlab.com/blog/furniture-testing/new-ansibifma-x-5-1-standard-for-office-seating
  2. Micom Lab: ANSI/BIFMA X5.11: www.micomlab.com/micom-testing/bifma-x5-11/
  3. Steelcase/Coalesse certificate citing X5.1-2017 (R2022): www.steelcase.com/content/uploads/2024/02/Coalesse-LessThanFive-seating-cert-2024.02.28.pd
  4. BIFMA G1-2013 summary: www.reminetwork.com/?p=2610
  5. UNMS preview of EN 1335-2:2018: normy.normoff.gov.sk/norma/128442/nahlad
  6. CATAS: EN 1335-1:2020 (PDF): catas.com/uploads/media/catas-en-1335-eng.pdf?v3.0
  7. SCS Global Services: BIFMA LEVEL: www.scsglobalservices.com/services/bifma-level

All sources checked 20 October 2026. Where a manufacturer does not publish a value, we say so rather than estimate it.

Cite this page

Best Office Chairs Europe, “EN 1335 vs ANSI/BIFMA X5.1”, https://bestofficechairs.eu/standards/en-1335-vs-bifma/, updated .