XRS 001
Technical reference. What is measured, how, and what the six levels mean. Free.
Documents
XRS 001:2026 — free, in five languages.
The technical reference is published under Creative Commons Attribution – NoDerivatives 4.0: read, cite, print, redistribute — in full and unaltered. The French text is authoritative; the four other editions are provided for information and carry the same pagination.
Technical reference · first edition · 2026-08
Respiratory protective devices — Human factors — XRS scale: breathing comfort classification of a mask from breathing resistance.
- FRXRS 001:2026(F) — Édition publique, texte faisant foiAppareils de protection respiratoire — Facteurs humains — Échelle XRS : classification du confort respiratoire d'un masque à partir de la résistance respiratoire. 36 pages, PDF.PDF
- ENXRS 001:2026(E) — Public edition, EnglishTranslation of the French authoritative text, same pagination. 36 pages, PDF.PDF
- ESXRS 001:2026(S) — Edición pública, españolTranslation of the French authoritative text, same pagination. 36 pages, PDF.PDF
- ZHXRS 001:2026(ZH) — 公开版，简体中文Translation of the French authoritative text, same pagination. 35 pages, PDF.PDF
- IDXRS 001:2026(ID) — Edisi publik, Bahasa IndonesiaTranslation of the French authoritative text, same pagination. 36 pages, PDF.PDF
How to cite
XRS 001:2026, Échelle XRS, première édition, XALPES LLC. — XRS 001:2026, XRS scale, first edition, XALPES LLC.
Citation for study, teaching, research or comparison is free, with full attribution mentioning the reference number, the edition and the publisher. The ™ symbol is placed on the first or most prominent occurrence of each mark in a document; it need not be repeated.
Licence of the text
CC BY-ND 4.0 covers the text of the reference. It grants nothing on the marks XRS™ and XALPES™, whose commercial use — designating, qualifying, labelling or marketing a product — remains subject to the written authorisation of XALPES LLC under the licence. Reading and redistributing the reference is free; printing XRS on a product is not.
Editions and archive
Every change is an indexed edition, with its reason.
The first edition is the founding edition. It is complete as to the construction of the scale, its physical basis, its documentary verification and its physiological conformity check; the human-panel validation of Clause 14 remains to be conducted, and every level declared on the basis of this edition must mention that status.
Any modification of a threshold, a qualification or a breathing endurance gives rise to a new indexed edition accompanied by the justification and the data that motivated it. Earlier editions are kept on this page, marked as superseded, so that a third party can reconstruct the history of decisions. Declarations in force remain valid until their term under the edition that founded them.
| Edition | Date | Status | Changes |
|---|---|---|---|
| XRS 001:2026 | 2026-08 | Current | Founding edition. Public editions in five languages issued 2026-09. |
This edition is published openly and calls for criticism. Comments on the position of the thresholds, the assumptions of the model, the values flagged as estimates and the validation protocol are welcome at contact@scalexrs.com.
The XRS document family
One public reference, three contractual annexes.
XRS 002
Technical annex of the licence: measurement conditions, declaration protocol, mandatory mentions, permitted forms, withdrawal grounds, normative lexicon of endurances.
XRS 003
Financial annex: full-cost method, published price list, degressivity, free cases, legal constraints on the price list, revision.
XRS 004
Artwork annex: graphic system, logotype and figurative elements, scale bar, panel dimensions and tolerances, QR code, master files, artwork control.
XRS 002, 003 and 004 are communicated to candidate licensees with the licence contract. Their substance — regimes, price list, mandatory mentions, panel — is summarised on the licence and marking pages of this site so that nothing a licensee commits to is hidden from the public.