UNI EN 1149-5
Protective clothing with electrostatic properties

UNI EN 1149-5:2018 standard specifies the material and design requirements for electrostatic dissipative protective clothing used as part of a total earthed system to prevent discharges that can trigger fires.
These requirements may be insufficient in flammable oxygen-enriched atmospheres.
The UNI EN 1149-5: 2018 standard does not apply to protective gloves or footwear that dissipate electrostatic charges, which are separate and do not form an integral part of the clothing and does not apply to protection against mains voltage.

Why choose anti-static clothing

Static electricity is a surface phenomenon that occurs when two bodies come in contact with each other and then are separated. Under special conditions (type of material and atmospheric conditions), electrical charges are created that can be of varying charge (field strength) depending on various factors such as:

The material and its physical and electrical properties;
Temperature;
Humidity;
Pressure;
The separation speed of the two bodies.
The higher the pressure or the separation speed, the greater the charge.

Scope of Application

Static electricity is a carrier of very little energy, which is formed and discharged continuously without attracting our attention. This can be a danger when working in contact with electronic circuits because it could cause fires at any time.
Antistatic workwear has several scopes, such as:

- Electronic and electrotechnical companies;
- Health: dental practices, analysis laboratory, radiology, cardiology, hyperbaric chamber, operating theatres;
- Chemical companies;
- Companies with spray booths and paint factories;
- Storage areas for goods, gas and flammable material;
- Automotive industries;
- Oil industries or distributors of energy sources;
- ATEX (ATmosphere EXplosives) areas that involve an atmosphere in which there is a mixture of flammable substances (in the form of gas, vapours, mists or combustibles) with air or comburent. In certain atmospheric conditions and specific concentrations, if ignited, the combustion spreads to the flammable mixture causing explosions.

Accidents resulting from the accumulation of static electricity are more common than we imagine: in the UK alone, more than one occurs every week. It is therefore important to identify general prevention and protection criteria in advance.

General requirements

camice donna bianco antinfortunistico antistatico

The general requirements of antistatic workwear, according to the UNI EN 1149-5:2018 standard, must have specific characteristics, such as:

They must cover the body and other non-antistatic clothing to ensure protection from risk;;
Accessories that make up the garment (such as labels and reflective strips) must be permanently attached to the garment;
Conductive parts such as zippers or buttons are allowed only if covered by the outermost material;
They must have points of contact with the body (conductive element);
Garments must be continuously earthed and therefore combined with specific footwear or the presence of earth floors or cables.

Carbon fibre has the ability to neutralize electrical charges and dissipate them, therefore it is very suitable for this type of safety clothing.

More on the EN 1149-5 standard

In addition to the UNI EN 1149-5:2018 standard, there are supplementary standards specifying the test methods to be adopted with regard to antistatic workwear:

UNI EN 1149-1:2006: To avoid discharges that can trigger fires, this standard specifies a test method for materials intended for the manufacture of electrostatically charged dissipating protective clothing (or gloves). The method does not apply to materials used in the manufacture of protective clothing or gloves against normal electrical voltages;
UNI EN 1149-2:1999: This standard measures the vertical electrical resistance of the materials making up the protective clothing. The standard is not applicable for protection against mains voltage.
UNI EN 1149-3:2005: This standard specifies the methods for measuring the dissipation of electrostatic charges from the surfaces of clothing materials.

Fabrics

Speaking of antistatic workwear, it is important to know that it can be made with two fabric types: with antistatic fabrics or with antistatic fibres.
Unlike surface treatments, the properties of the antistatic fibre are an intrinsic and permanent feature of the garment. This allows the garment to perform better.
Antistatic fabrics can be presented in two ways:

with a conductive surface grid. Using this fabric, an earth connection is required to dissipate electrical charges;
with dissipative core fibres, which dissipate part of the charges even if not earthed.