Here, you can read about protective clothing with electrostatic properties. EN 1149-3 and EN 1149-5 certification is for your safety.
Safety apparel where the surface material of the clothing is tested according to its electric discharge properties. This standard specifies workwear that is tested for its ability to dissipate electrostatic charge from the surface of the clothing material. The standard explains that the safety apparel has been tested for its ability to discharge electrostatic charges to the air and therefore won’t conduct it to the user of the clothing.
This standard describes the requirements for electrostatic properties for safety apparel used in areas where there is a hazard of sudden electrostatic discharge. The test method for EN 1149-5:2008 specifies the requirements for materials and design of safety clothing with electrostatic properties, in order to protect the wearer as best possible.
It is important that you are properly earthed when using safety apparel with electrostatic properties. This is ensured by using appropriate antistatic approved safety footwear.