Overview
ISO 20957-2:2020 specifies additional safety requirements and test methods for stationary strength training equipment. It is intended to be read together with ISO 20957‑1 (general safety requirements) and applies to strength training machines that use stacked weights or other resistance means (elastic cords, hydraulic, pneumatic, electrical, magnetic, springs, externally loaded weights). The standard covers equipment classes H, S and I defined in ISO 20957‑1 and focuses on design safety, structural loading, stability and performance testing.
Key topics and technical requirements
- Scope and classification
- Applies to selectorized, externally loaded, guided, user‑defined motion and stacked weight equipment for strength training.
- Stability
- Equipment must be stable under all loading and storage conditions; specific stability tests are defined for externally loaded and user‑defined motion equipment.
- Loading and structural strength
- Training weight posts (externally loaded) must resist high static loads (classes S and I: 6× the maximum load; class H: 4× the maximum load).
- Storage weight posts require specified single static load resistance (classes S and I: 4×; a reduced factor applies for class H - see the standard for exact value).
- Endurance and performance
- Fatigue/endurance tests for moving parts, catch mechanisms and guided carriages to ensure continued function after repeated use.
- User safety features
- Requirements for access to squeeze/shear points, weight disc clearance, weight disc retention, entrapment prevention, pull‑in points, drop stops and catch mechanisms.
- Marking and instructions
- Additional user instructions and safety markings specific to strength equipment.
- Test methods and reporting
- Detailed test procedures (dimensional, visual, tactile, performance) and requirements for documenting test results.
Practical applications and users
- Equipment manufacturers use ISO 20957-2:2020 to design and validate safe stationary strength machines (selectorized machines, Smith machines, leg/chest presses, weight stacks).
- Test laboratories and certification bodies apply the standard’s test methods to assess compliance and produce test reports.
- Gym operators, purchasers and facility managers reference the standard for procurement specifications and to ensure equipment safety for commercial use.
- Design engineers and safety managers use the requirements for risk reduction, component sizing (weight posts, guides, catch mechanisms) and labeling.
Related standards
- ISO 20957‑1 - General safety requirements and test methods (must be read in conjunction)
- ISO 20957‑4 - Free‑weight barbell racks (separate requirements)
- ISO 12100 - Safety of machinery - Risk assessment and risk reduction
Keywords: ISO 20957-2:2020, stationary training equipment, strength training equipment safety, test methods, stability, loading, stacked weights, selectorized equipment, externally loaded equipment.