The future lies in clothes that emit light

Jul 13, 2021 / Michal Jirák

We at CERVA have just one dream, which is that every craftsman or worker will wear Hi-Vis outdoor clothing. Our vision is reflected in the new Knoxfield collection. And how do we imagine the perfect Hi-Vis clothing will look like?

The perfect warning garment that can be seen under all circumstances consists of two individual parts:

  1. Retro-reflective bands made of billions of tiny beads that respond to such light sources as car lights and reflect it back.
  2. Material made using warning colours (yellow, red, orange), which will attract attention even without the presence of a light source.

This type of Hi-Vis clothing increases the visibility of a person at night up to ten times. However, it is important that the reflective bands and the waistband are applied to every side of the clothing.

Hi-Vis clothing does not help only at night, however. The clothing also contributes to a lower accident rate in those places in which the employees move between different means of transport in fog, rain or snow. Then the number of occupational injuries decreases not only on roads but also in forests, close to railway lines or at airports.

Everything according to standards

First of all, the materials and their placement on the clothing must comply with EN ISO 20471 of 2013 that replaced the previous EN 471. The older standard is now only applicable to clothing made during the period of validity of this standard.

The EN ISO 20471 standard classifies Hi-Vis clothing in 3 classes in accordance with a minimum area of reflective materials:

Material/Class Class 1 Class 2 Class 3
Background material 0,14m² 0,5m² 0,8m²
Retroreflective material


(5 cm wide bands with a minimum length of 2 m)
(7 cm wide bands with a minimum length of 1.4 m)


(5 cm wide bands with a minimum length of 2.6 m)
(7 cm wide bands with a minimum length of 1.9 m)


(5 cm wide bands with a minimum length of 4 m)
(7 cm wide bands with a minimum length of 2.9 m)

Combined performance material 0,2m²  

Hi-Vis + design + functionality = Knoxfield

Another trend in the world of Hi-Vis clothing are phosphorescent materials. Clothes that are exposed to sunlight or artificial light are then phosphorescent for tens of minutes even when the light stops shining. This technology will be useful, for example, in the event of a power outage.

RUSH+ GLOW goggles produced by Bollé make use of this phosphorescent effect. Once they are exposed to light you literally cannot be overlooked in the night. This is without mentioning their extreme resistance to breakage, scratching, dust and smoke.

Nothing to compare