By Mark Smith 01/10/2025

Under: PPE and Workwear

The Danger You Can't See with high visibility clothing

In high-risk environments, the margin between safety and disaster is often measured in seconds. High-visibility clothing is designed to close that gap, but not all hi-vis workwear is created equal and not every garment is suited for every condition. When workers wear the wrong class of hi-vis, they enter the visibility gap, a dangerous space where they appear less visible than they believe. This gap reduces detection time, increases accident risk, and can put both lives and legal compliance on the line.

Hi-Vis Clothing Classes Explained

In the UK, high-visibility clothing is regulated under EN ISO 20471, which sets three classes of protection:

Class 1 is the lowest level of protection for minimal risk/off-road purposes, with a minimum background material 0.14m² a minimum retro reflective material 0.10m². Class 1 vests are intended for use in areas where traffic is minimal, specifically in zones where vehicles travel at speeds below 25 mph. It's still important for workers to maintain a safe distance from traffic to reduce the risk of accidents. Class 1 vests are commonly worn by individuals who operate in low-traffic environments, like parking attendants and personnel working beside the road.

Class 2 is an intermediate level of protection for use on low-speed roads. Minimum background material 0.50m², minimum retro reflective material 0.13m². Class 2 vests are specifically crafted for individuals who operate in areas with heavy traffic and challenging visibility, particularly during poor weather conditions. In such environments, vehicles may travel at speeds exceeding 25 mph. Class 2 vests are particularly beneficial for workers positioned a safe distance away from the main flow of traffic. Examples of roles that commonly use these vests include airport personnel, forest workers, and toll booth operators.

Class 3 is the highest level of protection for use in all areas.  Minimum background material 0.80m², minimum retroreflective material 0.20m². Class 3 vests are specifically made for environments where traffic is intense, and speeds can surpass 50 mph. You’ll often see site inspectors, railway personnel, and emergency responders sporting these vests. It’s particularly important for workers operating near roadways at night to don Class 3 vests for their safety.
The higher the class, the greater the visibility and protection. The common mistake? Wearing Class 1 or 2 in Class 3 environments because it’s lighter, cheaper, or “what’s available.” 

Does high-visibility clothing actually work?

Research and accident statistics demonstrate that hi-vis clothing significantly lowers the chances of accidents by enhancing the visibility of workers to drivers, machinery operators, and their teammates.

The bright fluorescent materials play a key role in making individuals stand out in daylight, while the retro-reflective strips boost visibility at night when light hits them.

Which colours are considered high visibility?

Based on UK and EU standards, there are three specific fluorescent colours that are recognised:

•    Fluorescent Yellow
•    Fluorescent Orange
•    Fluorescent Red

While other bright shades like green or blue might catch the eye, they do not fulfil the legal criteria for workplace safety.

What is considered the best high-visibility colour?

It varies with the setting:

•    Yellow: The most common choice, suitable for a wide array of conditions.
•    Orange: Often mandatory for rail workers in the UK to ensure they stand out against green backdrops.
•    Red: Though less frequent, it serves a purpose in specific, specialised job roles.

Fluorescent yellow is widely regarded as the most visible colour and is extensively utilised across various industries, including construction. High visibility clothing is not just about wearing bright fabric; it’s a crucial piece of regulated personal protective equipment (PPE) that can save lives. Selecting the appropriate class and colour, along with proper maintenance, is essential for ensuring safety and compliance at work.

What exactly is the Visibility Gap?

This term refers to the dangerous disconnect between how visible a person thinks they are and their actual visibility in real-world scenarios. Many workers mistakenly believe that any high-vis clothing will do. However, several factors influence visibility:

•    Lighting conditions (dawn, dusk, night, fog)
•    Nearby vehicle speeds
•    Complexity of the background (machinery, traffic, foliage)
•    Weather conditions (rain, glare, snow)

All of these elements can affect detection distance and reaction time. Wearing the incorrect class of hi-vis can shorten the time a driver or machine operator has to spot and react to you.

Let’s delve into the real risks associated with wearing the wrong class:

1.    Reduced Detection Distance: A driver traveling at 50 mph covers about 22 meters every second. If your clothing blends into the surroundings for even a second longer, that could mean the difference between a safe stop and a collision.
2.    False Sense of Security: Workers might think, "I’m wearing hi-vis, so I’m safe," without realising that their garment may not be suitable for night-time or for the speed of nearby traffic.
3.    Background Camouflage: Yellow vests can become invisible against industrial machinery or traffic cones; orange might blend into fall foliage or clay dirt.
4.    Legal and Financial Exposure: In the UK and EU, compliance with EN ISO 20471 is mandatory in many work environments. 

How do we close the Visibility Gap? 

Here’s an action plan:

1.    Audit Your Work Environments: Evaluate lighting, vehicle speeds, and the complexity of visual backgrounds.
2.    Match Hi-Vis Class to Risk Level: Always err on the side of higher visibility, as downgrading for comfort can be a costly mistake.
3.    Train Your Workforce: Visibility goes beyond PPE; it encompasses positioning, awareness, and correct maintenance.
4.    Maintain Your Gear: Dirt, fading, and wear can downgrade a Class 3 vest to Class 1 performance.
5.    Consider Advanced Options: Look into LED-integrated vests, waterproof Class 3 jackets, or breathable mesh designs suited for warmer climates.

Your safety can be measured in seconds. In environments with heavy machinery and fast-moving vehicles, every moment counts. You might not feel the danger of wearing the wrong class of hi-vis until it’s too late. The cost of upgrading to the correct class? Minimal. The cost of not upgrading? Potentially everything. Speak with our experts today to order the right class of hi-vis for your team. 

FAQ for Hi-Vis workwear

How often should you replace high-visibility clothing?

It's time to replace hi-vis garments when:
•    The fluorescent material begins to fade
•    The reflective strips become cracked, dull, or lose their shine
•    The garment is torn or too dirty to clean effectively.

Typically, employers opt to replace hi-vis clothing every 6 to 12 months, but this can vary based on usage and the severity of the work environment.

How to clean high-visibility clothing

To maintain the effectiveness of hi-vis workwear:
•    Wash it at the temperature suggested on the care label (usually a maximum of 40°C). Some manufacturers guarantee hi-vis effectiveness for up to 50 washes. 
•    Steer clear of bleach and fabric softeners, as they can damage reflective strips
•    Turn garments inside out before washing
•    Air dry whenever you can, since tumble drying may shorten the lifespan of the clothing.

When do you need to wear a high-visibility jacket?

It's essential to don hi-vis clothing whenever you're in situations where visibility is vital for safety. This is particularly important in places like:

•    Roadside or rail work
•    Construction sites
•    Warehouses with vehicle traffic
•    Night work or areas with low lighting.

Employers are legally obligated to provide PPE, including hi-vis clothing, in scenarios where other safety measures won’t suffice.

Where can I buy a high-visibility vest?

At Enfield Safety, we offer a broad selection of hi-vis vests. All of our vests are CE-marked and meet the EN ISO 20471 safety standards. Shop online today or speak with a member of our team.