ISO 11839:2021 PDF

Machinery for forestry — Thrown object guard — Test method and performance criteria

Open preview (PDF)

Title (English):

ISO 11839:2021

Machinery for forestry — Thrown object guard — Test method and performance criteria

Document status:: Active
Format:: Electronic (PDF)
Number of pages:: 10
Publication date:: February 19, 2021
Edition:: ISO IS 11839 edition 2 version 1
ICS:: 65.060.80

Delivery type:

Full version25 €Read online 24h10 €Read online 72h15 €

Document language:

enru

Delivery time:Immediate download

Price:25 €

Description (English):

This document establishes a laboratory test method and performance requirements for thrown object guards (TOG) that provide operator protection against thrown objects. This applies to mobile and self-propelled machinery used in forestry and related operations including, but not limited to, those defined in ISO 6814. The TOG is intended to provide reasonable protection for the operator on the host machine from powered rotating cutting or grinding elements and residual matter thrown by an attachment on the host machine. As the tests in the document are dependent upon the mass, velocity, and the cutting or grinding element profile, the TOG meeting the requirements of this document are specific to each cutting or grinding attachment and the host machine model. This document does not address protection from saw chain shot. NOTE A separate standard ISO 21876 addresses saw chain shot hazards.

Technical details

Technical committee: ISO/TC 23/SC 15 - Machinery for forestry
SKU: ISO 11839:2021

Abstract

Overview

ISO 11839:2021 - Machinery for forestry - Thrown object guard - Test method and performance criteria - defines a laboratory test method and performance requirements for thrown object guards (TOG) intended to protect operators of mobile and self‑propelled forestry machinery from cutting or grinding elements and residual matter thrown by attachments. The standard applies to TOGs incorporated into operator protective structures (ROPS/FOPS/OPS) or provided as independent guards. Tests are specific to each cutting or grinding attachment and host machine model and do not cover saw chain shot (see ISO 21876).

Key Topics

Scope and purpose: Establishes repeatable laboratory procedures and pass/fail performance criteria for TOG effectiveness against projectiles generated by powered cutting or grinding attachments.
Risk assessment: Requires a prior risk assessment (ISO 12100) to identify panels in the operator’s path and to determine worst‑case mass and tip velocity for the cutting/grinding element.
Impact objects (F1, F2, F3):
- F1 / F2 profiles: Representative sawtooth profiles for circular disc saws (shankless and shank types).
- F3 profile: Spherical impact object with mass selected from defined ranges (actual or standardized masses: <250 g = actual mass; 250–399 g = 325 g; 400–599 g = 500 g; 600–999 g = 800 g; 1 000–1 599 g = 1 300 g; 1 600–2 600 g = 2 100 g; >2 600 g = actual mass).
Instrumentation & accuracy:
- Mass scale accuracy ±1% of impact object mass.
- Velocity measurement accuracy ±2 m/s.
- Materials per ASTM A‑108 (or equivalent) for impact objects.
Launcher & test setup: Controlled impact object launcher (sabot permitted) that sets orientation, direction and velocity; test velocity derived from kinetic energy equivalence calculations:
- KE = 1/2 m0 v0^2
- vt = sqrt(2·KE / mt)
- vp = (cos θ) · vt
Safety: Dynamic projectile testing demands containment structures and laboratory risk controls.

Applications

Manufacturers and designers of forestry machinery and thrown object guards (TOG) use ISO 11839:2021 to:
- Validate TOG designs for specific cutting/grinding attachments and host machines.
- Inform selection of panel materials, mounting hardware and integration with ROPS/FOPS/OPS.
Independent testing laboratories implement the laboratory test method and reporting requirements.
Safety engineers, conformity assessors and procurement teams use the standard for specification, compliance and performance verification.

Related standards

ISO 12100 - Risk assessment and risk reduction
ISO 6814 - (related forestry machinery definitions)
ISO 21876 - Saw chain shot hazards (separate standard)
ISO 898‑1 / ISO 898‑2 - Fastener mechanical properties
ISO 9248, ISO 3411, ASTM A‑108 - referenced test/measurement and material standards

Keywords: ISO 11839:2021, thrown object guard, TOG, forestry machinery, test method, performance criteria, impact object, kinetic energy, operator protection.

Related standards

Standards mentioned in the description

Abstract

Overview

Key Topics

Scope and purpose: Establishes repeatable laboratory procedures and pass/fail performance criteria for TOG effectiveness against projectiles generated by powered cutting or grinding attachments.
Risk assessment: Requires a prior risk assessment (ISO 12100) to identify panels in the operator’s path and to determine worst‑case mass and tip velocity for the cutting/grinding element.
Impact objects (F1, F2, F3):
- F1 / F2 profiles: Representative sawtooth profiles for circular disc saws (shankless and shank types).
- F3 profile: Spherical impact object with mass selected from defined ranges (actual or standardized masses: <250 g = actual mass; 250–399 g = 325 g; 400–599 g = 500 g; 600–999 g = 800 g; 1 000–1 599 g = 1 300 g; 1 600–2 600 g = 2 100 g; >2 600 g = actual mass).
Instrumentation & accuracy:
- Mass scale accuracy ±1% of impact object mass.
- Velocity measurement accuracy ±2 m/s.
- Materials per ASTM A‑108 (or equivalent) for impact objects.
Launcher & test setup: Controlled impact object launcher (sabot permitted) that sets orientation, direction and velocity; test velocity derived from kinetic energy equivalence calculations:
- KE = 1/2 m0 v0^2
- vt = sqrt(2·KE / mt)
- vp = (cos θ) · vt
Safety: Dynamic projectile testing demands containment structures and laboratory risk controls.

Applications

Manufacturers and designers of forestry machinery and thrown object guards (TOG) use ISO 11839:2021 to:
- Validate TOG designs for specific cutting/grinding attachments and host machines.
- Inform selection of panel materials, mounting hardware and integration with ROPS/FOPS/OPS.
Independent testing laboratories implement the laboratory test method and reporting requirements.
Safety engineers, conformity assessors and procurement teams use the standard for specification, compliance and performance verification.

Related standards

ISO 12100 - Risk assessment and risk reduction
ISO 6814 - (related forestry machinery definitions)
ISO 21876 - Saw chain shot hazards (separate standard)
ISO 898‑1 / ISO 898‑2 - Fastener mechanical properties
ISO 9248, ISO 3411, ASTM A‑108 - referenced test/measurement and material standards

Keywords: ISO 11839:2021, thrown object guard, TOG, forestry machinery, test method, performance criteria, impact object, kinetic energy, operator protection.

ISO 11839:2021 PDF

Technical details

Abstract

Overview

Key Topics

Applications

Related standards

Related standards

Abstract

Overview

Key Topics

Applications

Related standards

Related standards

Machinery for forestry. Saw chain shot protective windows. Test method and performance criteria.

Safety of machinery - Relationship with ISO 12100 - Part 5: Implications of artificial intelligence machine l…

Machinery for forestry - Mobile and self-propelled machinery - Terms, definitions and classification

Mechanical properties of fasteners made of carbon steel and alloy steel - Part 1: Bolts, screws and studs wit…

Fasteners - Mechanical properties of fasteners made of carbon steel and alloy steel - Part 2: Nuts with speci…

Earth-moving machinery — Units for dimensions, performance and capacities, and their measurement accuracies

Earth-moving machinery - Physical dimensions of operators and minimum operator space envelope (ISO 3411:2007)