Sources and method

RopeFactor calculations are based on the standards and technical references listed below. The applicable source is identified in the calculation report where each result is shown.

Calculation development

The RopeFactor calculations are maintained in a reference workbook, which is the source of truth for the mathematics. The web application implements the same calculation logic, ported cell by cell. Automated test cases compare the application results against the workbook to identify differences between the two.

A test harness drives the real workbook — opening it, writing the inputs of a case, recalculating, and reading the answers back out.
Those answers are locked in as fixtures, and more than 900 automated tests assert the software reproduces them, most to within one part in a billion.
Differences between the application and the workbook are treated as calculation issues and reviewed before the application result is accepted. Errors found in the workbook this way are corrected at source.
The version stamp on every report names the workbook revision the result came from.

Standards

Codes and standards the calculations follow
Standard	Used for
ISO 8100-1:2026	Sheave-to-rope diameter ratio; the flat factor-of-safety floor
ISO 8100-2:2026	Factor of safety (Formula 36, N_equiv), traction, emergency braking, the stalled condition
ISO 4344:2022	Rope catalogue — minimum breaking force, mass and metallic area; discard criteria
ASME A17.1-2022 / CSA B44:22	Minimum and actual factor of safety; sheave pitch diameter; Appendix U conformance
ASME A17.6-2022	Rope catalogue, Mandatory Appendix I
EN 12385-2 · ISO 17893	Metallic area factor for elongation
ISO 12076	Rope modulus test basis
VDI 2358	Rope terminology and properties

Literature

For calculations not prescribed by the elevator code — rope life, elongation, rope dynamics and groove pressure — RopeFactor uses the technical references below, cited in the report at the point of use.

K. Feyrer, Wire Ropes: Tension, Endurance, Reliability, 2nd edition (Springer, 2015) — bending fatigue, the force factors, groove pressure, rope discard. The primary source for rope life.
Palmgren-Miner cumulative damage — accumulation across the bend types.
Donandt and Berner (via Feyrer §3.1.7.2) — groove pressure for undercut and V grooves.
Holeschak — the floor-count factor relating trips to bending cycles.
P. Andrew & S. Kaczmarczyk, "Rope Dynamics", Elevator World, July 2011 — lateral and longitudinal rope frequencies, the quasi-stationary validity ratio.
S. Kaczmarczyk, Journal of Sound and Vibration 208(2), 1997.
L. Sun, "Building Sway and Elevator Rope Vibration", Elevator World, 1995 — the rope-weight correction and building sway coincidence.
M. Hadjzaman, "Traction Elevators: A Comparative Study on Wire Rope Stretch", Elevator World, February 2018 — the elongation method.
W. Scheunemann, W. Vogel & T. Barthel, "Steel Wire Ropes for Traction Elevators", Elevator World, July-September 2009.
Bethlehem / Wirerope Works technical bulletins EL-TB-05 and EL-TB-11 — elongation behaviour and field vibration context.
AISI Wire Rope Users' Manual; BRIDON, CIMAF and Gustav Wolf published rope data — constructional stretch and modulus ranges.

Standards are referenced but are not reproduced in full. Where a table is shown on this site it is a reference reproduction of tabulated values with the source named. Requirements should be verified against the applicable published standard and the code edition adopted by the project jurisdiction. RopeFactor is not affiliated with or endorsed by ISO, ASME, CSA or any rope manufacturer.

Software

RopeFactor is built on open-source work:

React and Vite (MIT) — the interface and the build.
react-pdf (MIT) — the calculation report is generated as true vector PDF in the browser.
TypeScript (Apache-2.0) and Vitest (MIT) — types and the test suite.
IBM Plex Sans, Mono and Spectral (SIL Open Font License 1.1) — the typefaces throughout the interface and the report, served from this site rather than a font CDN.
Vercel hosting; Upstash Redis for the beta list.