Hi-Visibility Standards – EN ISO 20471 Explained

Hi-vis clothing is essential for keeping workers safe when working near traffic, cranes, forklifts, or other vehicles, especially at night or in low-light conditions. Hi-vis clothing comes in many different options: vests, fleeces, trousers, t-shirts, polos, hoodies—essentially, any type of workwear garment likely has a high visibility equivalent.

The primary role of hi-vis clothing is to ensure workers are easily seen against their background environment from all angles, thereby reducing the risk of accidents on site. Given its vital role in safety, hi-vis garments are standardised, controlled by legislation, and certified accordingly. The current legislated standard certification is EN ISO 20471.

EN ISO 20471 defines high visibility clothing as:

Hi-vis clothing acts as a warning signal, ensuring workers are visible in risky situations. It’s crucial for anyone wearing or overseeing the use of hi-vis clothing to understand the standards and classes related to their specific job requirements.

EN ISO 20471: 2013 for High Visibility Clothing was released in 2013, replacing EN 471: 2003 A1: 2007 as the international standard for safety testing methods of hi-vis workwear in high-risk environments. The specifications require that high visibility clothing must visually signal the user’s presence and describe tests to evaluate retro-reflective materials for durability and effectiveness.

The standard covers the fluorescent fabric colour, minimum areas of reflective strips, and their placement to ensure visibility from all sides of the wearer. Compliance is about the wearer, not the garment itself. For example, a pair of hi-vis trousers must be worn correctly to comply. Altering or not maintaining the garment can reduce its effectiveness.

EN ISO 20471 introduced improvements over EN 471, including a stronger distinction between different risk situations. Compliance is now more focused on the wearer, defining different sections of the body for clarity:

• Torso only: Vest, gilet, polo shirt, or t-shirt
• Torso & arms: Long-sleeved t-shirt, polo, jacket, or coat
• Legs: Long-legged over-trousers or full-length trousers
• Torso & legs: Long-legged trousers with a t-shirt
• Torso, arms & legs: Trousers with a long-sleeved jacket or polo

Class 3 compliance requires that fluorescent fabric must cover either the torso and arms or the torso and legs with reflective bands visible at all times. Sleeves that obscure the band must also have reflective bands.

The standards ensure materials’ dimensional stability, thermal resistance, and tensile strength, making garments suitable for high-risk conditions. Reflective tapes must maintain compliance under normal use, and contrast materials should not bleed onto the hi-vis fabric.

Hi-vis garments consist of three main components:

• Fluorescent fabric: Enhances visibility in daylight and low-light conditions.
• Reflective strips: Retro-reflective materials reflect light back towards the source, crucial for nighttime visibility.
• Contrast materials: Added to areas prone to dirt to prevent contamination of the hi-vis fabric, thus extending the garment’s compliance and lifespan.

Hi-vis garments are classified based on the amount of fluorescent and reflective material:

• Class 1: Lowest level of visibility, single garments worn alone.
• Class 2: Intermediate visibility, such as a standard sleeveless hi-vis vest.
• Class 3: Highest visibility, often a combination of garments like a jacket with sleeves or trousers with a hi-vis polo shirt.

Custom logos can cover fluorescent material, reducing the garment’s effectiveness. Employers should discuss with suppliers to ensure compliance when adding branding.

To maintain compliance, follow care instructions and be mindful of the garment’s wash lifecycle—typically a maximum of 25 washes. Dirty or over-washed hi-vis garments reduce visibility and increase accident risk.

Replace hi-vis garments when they no longer comply with safety standards. Typically, this means every 6-12 months, depending on use and washing frequency. Rotating multiple garments can extend their lifespan.

By understanding and adhering to EN ISO 20471 standards, employers and workers can ensure maximum safety and visibility in high-risk environments.