Access is not required during normal operation
Based on the risk assessment, a fixed guard will generally be the preferred option.
Access is infrequent and the guard can be removed easily
A fixed guard designed for removal using a tool may be appropriate.
Regular access is required
An interlocked movable guard will generally be preferred.
Access is required during each operating cycle
An interlocked movable guard, guard locking system or another protective device may be required depending on stopping time, approach speed, access pattern and safety-related control-system performance.
The machinery contains multiple hazard zones
A combination of fixed, movable and interlocked guards may be necessary.
The hazard cannot be fully enclosed
An adjustable or self-closing guard may be required depending on the risk assessment and machine stopping behavior.
The machinery forms part of a large automated cell
Distance guarding should generally be used together with controlled, interlocked access.
Design review checklist
The standard is broader than fence height and panel strength. It connects the physical guard with foreseeable tasks, the working environment, human behaviour and the information needed to keep the guard effective in service.
Access and tasks
Where practicable, routine adjustment, lubrication and maintenance should be possible without opening or removing guards. Where entry is needed, the access route should be considered deliberately.
Visibility
Where process viewing is required, guard design and material selection should provide useful sightlines. For mesh guarding, open area, colour and the background behind the mesh affect visibility.
Structure
Posts, frames, mountings and infill need to resist foreseeable loading and deformation—particularly where movement could reduce the separation from a hazard.
Materials
Impact, ejected parts, corrosion, temperature, cleaning chemicals, hazardous substances, noise, radiation and other foreseeable conditions can change the guard construction required.
Human factors
Guard weight, operating force, sharp edges, trapping points, poor access and climbable details can undermine an otherwise strong design.
Fastenings and service
Removable fixed guards should require a tool, and where foreseeable maintenance requires removal, retained fastenings help reduce the risk of missing or unsuitable replacement fixings.
Verification and handover
ISO 14120 identifies verification methods that can include inspection, practical testing, measurement, observation, review of the task-based risk assessment and review of specifications or documentation. Information for use should cover installation, operation, removal, inspection and maintenance. That makes as-built dimensions, fixing details and service information commercial deliverables—not paperwork added at the end.
Build the complete standards path
ISO 14120 covers the guard itself. Risk assessment, reach prevention, interlocking and safeguard positioning are handled through related standards.
Risk assessment and the overall machinery risk-reduction process.
Read the ISO 12100 guideSafety distances intended to prevent hazard zones being reached by upper and lower limbs.
Read the ISO 13857 guideDesign and selection of interlocking devices associated with guards, including foreseeable defeat.
Read the ISO 14119 guidePositioning safeguards in relation to human approach and machine stopping behaviour.
Read the ISO 13855 guideA practical map of the core machinery-safety standards and the engineering question each one answers.
Explore the ISO standards hubA relevant Type-C standard can supplement or modify general requirements for a particular machine or machine group.
View ISO 14120 at ISOPractical information only. This page does not replace the standard, a machine-specific risk assessment, competent engineering advice or applicable legal requirements.
AS 4024 is the broader Australian machinery safety framework covering risk assessment, safeguarding, control systems, emergency stops, safety distances and machine integration. ISO 14120 specifically focuses on the design and construction of fixed and movable guards.
In practice, ISO 14120 forms one part of the wider AS 4024 machinery safety framework. A machine guard may meet ISO 14120 design principles while still requiring additional considerations under AS 4024, such as interlocking, safety distances, emergency stops and risk reduction measures.
