EN ISO 20471

What EN ISO 20471 is

EN ISO 20471 is the European standard covering high-visibility clothing — garments designed to make the wearer clearly visible to drivers, plant operators, or other people in hazardous work areas, in both daylight and low-light/dark conditions. It sets minimum requirements for the colour and reflective performance of the materials used, how much of the garment must be covered by them, and how they must be positioned on the body.

It’s the direct successor to the older EN 471 standard. Because safety certificates carry a five-year validity, garments certified only to the old EN 471 standard are no longer considered compliant, and current hi-vis workwear should be certified to EN ISO 20471.

The two materials involved

Hi-vis garments rely on two distinct materials working together:

• Background (fluorescent) material — the bright fluorescent yellow, orange, or red fabric that increases visibility in daylight, by standing out strongly against natural and industrial backgrounds.
• Retroreflective material — the reflective strips/tape that bounce light back toward its source, improving visibility in the dark or at dusk. This only works when illuminated by a light source (e.g. vehicle headlights) — it doesn’t glow or self-illuminate.

Some garments also use combined-performance materials that provide both properties in a single fabric, which the standard treats as a separate material category with its own minimum area requirements.

The three visibility classes

EN ISO 20471 defines three classes, based on the total minimum surface area of background and retroreflective material a garment must contain. The higher the class, the greater the visibility and the higher the risk level it’s intended for:

Class	Background material (min.)	Retroreflective material (min.)	Typical risk environment
Class 1	0.14 m²	0.10 m²	Low-risk environments — low traffic/machine activity, low vehicle speeds (commonly cited up to ~30 km/h)
Class 2	0.50 m²	0.13 m²	Medium-risk — moderate traffic or machine activity
Class 3	0.80 m²	0.20 m²	High-risk — low-visibility conditions (darkness, rain, fog) or proximity to fast-moving traffic, e.g. motorways or railway lines

Class 3 typically requires coverage of the torso and the arms/legs (full sleeves and trousers, or a combination of garments achieving equivalent coverage), since visibility needs to be maintained from every angle at higher risk levels — Class 1, by contrast, may only require reflective bands on the torso and limbs.

Important: these minimum areas are measured on the smallest garment size in a manufacturer’s range, with all adjustable fasteners set to their smallest configuration — so the same design can’t simply claim a class based on a larger sample size.

Achieving Class 3 through combined garments

A worker doesn’t necessarily need a single Class 3 garment — the standard allows Class 3 visibility to be achieved by wearing two or more certified garments together (e.g. a Class 2 jacket plus separately certified trousers) whose combined fluorescent and retroreflective area meets the Class 3 thresholds, rather than requiring every individual item to be rated Class 3 on its own.

Placement and design requirements

Beyond total area, EN ISO 20471 also specifies where the materials must be positioned, to ensure the human form remains recognisable from a distance:

• Background material must encircle the torso (and sleeves, on garments covering the arms), maintaining a minimum width/height of 50mm — interruptions caused by retroreflective bands crossing it don’t count against this.
• Retroreflective bands must be at least 50mm wide.
• For garments covering only the torso, retroreflective bands must encircle the torso (within ±20° of horizontal) and connect over each shoulder from front to back; if a single band is used, its lowest edge must sit at least 50mm above the garment’s bottom hem; multiple horizontal bands must be at least 50mm apart.
• These placement rules exist specifically to preserve the recognisable outline of a human figure at a distance and in the dark — a large area of reflective material randomly placed wouldn’t meet the standard even if the total area was sufficient.

Testing after cleaning

Because fluorescent colour and reflectivity degrade with washing and use, EN ISO 20471 requires both background and retroreflective materials to still meet their performance requirements after cleaning:

• If the manufacturer specifies a maximum number of cleaning cycles, testing is carried out after that many cycles.
• If no maximum is specified, testing defaults to five cleaning cycles.
• The cleaning process itself must follow the manufacturer’s instructions, based on standardised test procedures — this is meant to give buyers a realistic picture of how the garment ages in service, not just its as-new performance.

Risk-based selection

The standard includes an informative risk-assessment framework (based on factors like traffic speed, weather/visibility conditions, and complexity of the working environment) that maps roughly onto the three classes as low, medium, and high risk. This is meant to guide selection — rather than picking the highest class by default, the intended approach is to assess the actual risk of a role or task and select the minimum class that adequately addresses it, informed by a proper risk assessment for the specific working environment.

Country/sector-specific extensions

Some sectors apply additional or stricter requirements on top of the base EN ISO 20471 standard. For example, in UK rail, RIS-3279-TOM builds on EN ISO 20471 but requires a higher concentration of high-visibility orange fabric and a minimum photometric performance for the reflective tape (commonly cited as ≥330 cd/lx·m²) — a garment meeting base EN ISO 20471 requirements alone may not be sufficient for that specific sector without also meeting the sector-specific extension.

PPE Category classification

EN ISO 20471 garments generally fall under Category II of the EU PPE Regulation — a lower-risk category than Category III standards like EN ISO 11612 or EN 13034, reflecting that the hazard being addressed (being overlooked, rather than direct injury from heat, chemicals, or electricity) is treated differently under the regulation, though it remains a serious and safety-critical consideration in its own right.

What EN ISO 20471 does NOT guarantee

• It does not address any hazard other than conspicuity — an EN ISO 20471 garment provides no thermal, chemical, arc flash, or mechanical protection on its own. Multi-hazard garments must be separately certified against each relevant standard.
• Retroreflective performance depends on an external light source — it does not make the wearer visible in complete darkness without illumination from vehicle headlights or similar.
• Old EN 471 certification is not valid indefinitely — given the five-year certificate validity, older stock or documentation referencing only EN 471 should be treated as outdated for current compliance purposes.
• Meeting the base standard doesn’t guarantee compliance with sector-specific extensions (e.g. rail, aviation ground crew) that impose additional requirements beyond EN ISO 20471 itself.

Quick summary

Aspect	EN ISO 20471 detail
Supersedes	EN 471 (certificates expired after 5-year validity)
Materials assessed	Background (fluorescent) material, retroreflective material
Classes	Class 1 (low risk) – Class 2 (medium risk) – Class 3 (high risk)
Minimum areas	Class 1: 0.14m² / 0.10m² · Class 2: 0.50m² / 0.13m² · Class 3: 0.80m² / 0.20m² (background/retroreflective)
Placement rules	Min. 50mm band widths; torso encircled; shoulder connections for torso-only garments
Post-cleaning testing	After manufacturer’s max wash cycles, or 5 cycles if unspecified
Achieving Class 3	Single garment, or combination of certified garments meeting the combined area threshold
PPE Category	II
Doesn’t cover	Any hazard other than visibility — thermal, chemical, arc flash, etc. require separate standards