The decision to use shielding materials for shielding against high-frequency electromagnetic electrosmog RF and low-frequency electric fields NF is a clear YES to supporting one’s own health. These materials, however, are a sophisticated shielding technology which has certain characteristics that must be taken into account. On this FAQ page we present these collected so that the project SHIELD works completely and the goal is achieved.


Depending on the application, select the appropriate tab for details on the shielding material.

Grounding is one of the most common issues when shielding electric fields. These must always be carried out by the electrician.

Grounding instruction FPA

Large-area shields with shielding materials are not electrical equipment but “foreign conductive parts” according to IEV 826-03-03 or IEV 195-06-11 and thus a new method of DIN VDE 0100-100: 2009-06. By connecting to the equipotential bonding they are part of the electrical system, therefore, the recognized rules of technology must be observed.

According to the latest state of the art, a distinction is made between protection and functional potential equalization (FPA).

  • The protective potential equalization (green / yellow cable) is used for protection purposes and is intended to ensure dangerous contact voltages by rapidly triggering protective devices (such as circuit breakers).
  • Functional equipotential bonding (transparent cable) is used in large-area shielding to “minimize the emission of low-frequency electrical alternating fields”, ie the avoidance of Field displacements.
    The connection of a functional equipotential bonding conductor to a power distribution board is as follows:Scheme of a grounding FPA
  • Grounding is only permitted in buildings with TN-S, TT and IT systems. Under no circumstances may earthing be carried out in network forms with a combined PEN conductor!
  • A fault current circuit breaker (FI / RCD) of no greater than 30 mA must be installed!
  • For buildings with external lightning protection system, the provisions of DIN EN 62305-3 (VDE 185-305-3: 2006-10) must be taken into account.

Preferred order of how should be grounded

  • The functional equipotential bonding cable must be connected directly to the FPA busbar in the circuit distributor (fuse box) using a 4 mm² cable.
  • In exceptional cases, however, the functional equipotential bonding conductor can also be connected to “suitable protective conductors or protective compensation cables“. This exemption is important because otherwise no grounding would be possible in most homes without alterations to the fuse box.
  • Grounding with a 2,5 mm² cable to a protective conductor in the electrical installation.
  • Earthing with our GP grounding plug by screwing in the socket. Our earthing plug may only be plugged into a socket by a qualified electrician!
  • Less suitable are metal pipe systems or separate earthing rods that are not integrated in the building potential equalization. However, pipe cutters or roders – depending on the country – can make sense in network forms with a combined PEN conductor, but in this case common regulations of the respective countries must be observed.
Technical details grounding

The most frequently asked questions about shielding paints are paint selection, processing, substrate and ecology / environmental compatibility.

Top coatings / adhesive strength

Testing the tensile strength of YSHIELD shielding paints.

The adhesive tensile strength serves as a parameter for the adhesion of layers to a substrate. Our shielding paint are applicable inside, outside, under plaster and much more. And after the shielding paint a variety of top coats are used. The common question then is: which type of coating adheres to which shielding paint?


The tensile strength according to ASTM D4541, ISO 4624, DIN EN 13813 is determined under defined conditions (measuring surface, take-off speed, etc.). A tensile testing machine pulls the glued stamp down evenly until it breaks off. The adhesive tensile strength can never be higher than the intrinsic strength of the individual components, in the composite is always the weakest link prevail.

Tensile strength piston test Tensile strength piston test Tensile strength piston test Tensile strength piston test


Since we sell our shielding paint worldwide, it is not possible for us to name and test all variants of topcoats. It is therefore important to note that the application and processing is beyond our control. The following table should be an aid for information, no liability can be derived from the following table. In the case of uncertainty on site, we strongly recommend carrying out a test coating on a test surface.

Below is a table which gives advice on which types of coatings (paints, plasters, fillers) should always be compatible with which shielding paint: 


Dispersion (organic) from acryl, styrol, vinylacetat, polyurethan, epoxid + + + + + +
Silicate emulsion ((in)organic) from sodium silicate and plastic + + + + + +
Sol-silicate (inorganic) from sodium silicate and silica sol o o + + o o
Pure silicate (inorganic) from sodium silicate o
Silicon resin (organic) from organopolysiloxanes + + + + + +
Natural resin (organic)  o o
Casein (organic) 
Cellulose, glue (organic)
Lime, chalk (inorganic) o
Pit lime (inorganic)
Cement (inorganic)
Loam (inorganic) o
Clay (inorganic) o


Our shielding paint are very flexible and universally applicable. An advantage compared to wallpaper, fleeces or fabrics is the simple color typical processing. Every painter can professionally process our shielding paints with only one painter’s roller without special expertise or training. Even applying an airless spray with appropriate spray is easily possible.


Many metal shielding products are not corrosion resistant. Our shielding paints contain no metals but a mixture of carbons. These are chemically stable and permanently corrosion resistant, even in humid environments.


YShield has VOC (Volatile Organic Compound) and PAH (Polycyclic Aromatic Hydrocarbons) tested by TÜV SÜD.

  1. The current legal maximum VOC is 30 g / l, our shielding paints contain only 0,1 g / l to 1 g / l.
  2. The recommended maximum level of PAH (for category 1) is 0,2 mg / kg. Our shielding paints have 0,002 mg / kg and are thus even 100 times below the current recommendation for children’s toys.


Every aqueous paint must be preserved. Often disputed are isothiazolinone compounds, which, however, refers only to CIT and this is not included in our colors. We refuse a preservation as in eco-colors with BIT / silver, because we do not want to use nanosilver.

Our conservation with MIT / BIT has a very low allergenic potential, which many MCS customers confirm. And if a shielding paint is absolutely necessary, which is 100% free of preservatives, we have a wonderful alternative with our HSF64 shielding paint.


Due to the color-typical full-surface shielding without holes, our shielding paint offer a nearly linear shielding attenuation up to very high frequency ranges, without preferential polarization. This would be tested up to 18 GHz and thus our shielding paint are very future-proof.


Our shielding paints do not contain any solvents, plasticisers or other problematic ingredients. All ingredients were selected independently of price, solely for their safety and high quality.


Information and products for the necessary grounding, we have linked in the shop category grounding. See also the tab “Electrical”.


Detailed processing instructions can be found directly on the shielding paint in the shop and the linked technical data sheets on the corresponding product pages.

The most common questions about shielding fabrics are the choice of fabric and gentle cleaning of the shielding fabric.

Wash resistance

Shielding fabrics lose screen attenuation during washing and when moving. Since there are many false rumors circulating, we are releasing YShield’s ninth washing test of August 2016.


YShield has washed all the substances known on the market 50 times at 30 ° C. It was washed in parallel on 2 washing machines (BOSCH and SAMSUNG) and the values ​​averaged. The detergent used was a detergent suitable for silver substances.

Measurement methods

An interesting feature of the measurement procedure according to ASTM D4935-10 is that it measures radially, ie in all polarization directions, this is the closest thing to reality! With TEM measuring cells it is possible to measure from 30 MHz to 18 GHz in one pass.

Explanation of the following screen attenuation graph: The orange bar is the original screen attenuation without washing. The legend to the left of the scale represents the screen attenuation in dB at 1 GHz. Each additional bar represents “after 10 washes”.

Result at 30 ° C wash temperature

Washability of our shielding fabrics from YShield

Conclusion for washing resistance

All our shielding fabrics provide a good to very good result at 30 ° C wash temperature. This is because over the years we have removed all unstable materials from the range. Many shielding fabrics of the competition (not in the diagram) the measured values ​​speak a very clear language. We had fabrics at hand which fell from 30 dB to 7 dB after only 2-3 washes. If higher washing temperatures are necessary, this should be requested from us.

Tips on shielding fabrics

  • Detergent: Yshield has tested many different laundry detergents over the course of 9 washing tests (cheap, ecological, liquid, powdered, etc.). Enzymes, brighteners, fragrances and much more are lethal for the shielding of shielding substances. We generally recommend the TEXCARE detergent, as it is very gentle on shielding materials and is also ideally suited for allergy sufferers.
  • Drying: The best way to dry is to hang up only because the high temperatures in the dryer destroy the shielding fabrics. If it is absolutely necessary to use a dryer, ventilate only cold.
  • Ironing: Definitely: please do not iron! However, if ironing is absolutely necessary (as our shielding material Naturell wrinkles very strongly, for example), it is essential to use the lowest possible temperature at level 1 and also less steam.

Tpycial Discoloration

Fabrics with silver threads change color over time! Sometimes substances are already discolored when we get them from the manufacturer! This process is absolutely normal for silver. Reasons for this are sunlight, heat from the radiator, splashes of water, sweat, etc.. Discolored areas do not affect the shielding effect (screen damping) and are not a quality defect!

If you can not accept a discoloration, you will find in the shop various substances that can not discolor with it automatically associated much lower shielding attenuation. Here are a few examples of how such discoloration (worst case) might look like:

Typical discoloration of silver fabric which inevitably happen.
Typical discoloration of silver fabric which inevitably happen.


Fabrics with unprotected silver threads (Silver-Tulle, Silver-Elastic, Silver-Silk) have a limited shelf life. The lifetime basically depends on the frequency of the movement.

  1. Washing: Regular washing with suitable detergent 30 ° C is no problem, see washing test.
  2. Curtains: Even a curtain made of silver fabrics will last for years unless it is raised and pulled 10 times a day.
  3. Canopies: Canopies last longer if they are not completely hung away every day for bed making, so they are moved. Every day while traveling in a suitcase, silver canopies survive only a few months. Alternative: Canopies made of natural material last much longer, because the silver threads are insulated and additionally wrapped. When traveling, use our blanket or a steel-gray sleeping bag.
  4. Clothing: If our Silver-Elastic clothes are worn once a week in an emergency, they will last for years. If they are worn daily while sleeping, your sweat may be over after a few months. Alternative: For permanent use, we recommend a blanket or bed-linen made of steel-gray, this fabric keeps very long with its stainless steel threads.


More and more textiles for sports, atopic dermatitis, etc. contain nanosilver. Due to their size, these tiny nanosilver particles can penetrate the skin into any body cell and cause massive damage. The Federal Environment Agency warns of these serious knowledge gaps.

However, thick layers of “metallic silver” are harmless to humans and the environment. All our silver yarns as well as our full silvered textiles are covered with 99% “metallic silver”. Even if heavy particles (such as clothing or bedding) are released over time, they are far too large to penetrate the skin through the skin!

PROnatur24 also offers sewing for curtains!

Very popular are our custom-made curtains, which we sew very cheaply for end customers. You pay only the running meters of the corresponding material and proportionally the necessary sewing! Per curtain we need and charge 15 cm hem surcharge.

Which sewing works we can do

  • Curtains with a curtain tape at the top and a weight band below.
  • Curtains with a tunnel on top and a weight band below.
  • Ideally, the curtains have a rectangular shape. But we also try to implement other shapes and desires (eg Velcro) cost-effectively!
  • More expensive and thus higher in price are curtains with many individual loops, we will gladly make you a favorable offer.

Fabric widths

Our shielding fabrics have different widths from 130 cm to 260 cm. You can sew the fabric width or the fabric length either as height or width of the curtain. In the width of a curtain about 8 cm are lost by sewing. At height, about 15 cm are lost for the curtain and weighting band. How high and how wide a single curtain can be depends on the fabric width!

Example if you want to cover an area of ​​400 cm width and 230 cm height:

  • With Naturell you need 4,0 m because the 250 cm are sufficient for 230 cm height.
  • With Silver-Tulle you need 6,9 running meters for 3 curtains.

If you need help with planning we will be happy to help! 

Front / back

Some fabrics (e.g., Silver Twin, Steel Twin) have a lighter front and a darker back with the metal threads. This makes these fabrics wonderful for opaque curtains. The bright side towards the room is our standard. If you want the darker metal thread side towards the room, please let us know.

Dimensions / dimensional accuracy

We understand all dimensions you call us, as finished sewn final dimensions (including curtain tape, tunnel, sewn-in sides, etc.). For drapery you have to calculate 25 – 50% oversize in width! For most fabrics we achieve a dimensional accuracy of +/- 2 cm. Elastic fabrics (such as Silver-Tulle, Perspective) are difficult to sew, the dimensional accuracy can be up to +/- 5 cm!

Optimization of the shielding

In general, the shielding is more important than a perfect look!

  • Curtains over window sills must cover or rest on the sill, curtains in front of doors must touch the floor. Even if this is not perceived visually as nice – if the substances do not rest, radiation comes through the gap.
  • Window openings should always be covered 20 – 40 cm, so cover the wall with. Only when a screen overlaps with the shielding, a good shielding performance is achievable.
  • Curtains should always be hung with the least possible distance to the wall, the larger the distance, the larger the gap through which the high-frequency radio radiation can pass.

YSHIELD has been developing carbon inks for shielding electromagnetic fields since 2003. Since then, tens of thousands of color samples have been mixed and many millions of Euros have been invested in the development. Not only end customers and building biologists have successfully shielded countless projects with thousands of tons of HSF54. For RFID shielding, many fashion companies in all stores worldwide trust in YSHIELD products, e.g. Zara, Levis, Esprit. Data centers worldwide are shielded with the HSF54 shielding color by e.g. Apple, Amazon, AT&T. Military customers use the HSF54 to shield small systems up to complex buildings. This in itself proves the high quality of YSHIELD products.

In addition, the production of these shielding colours is monitored by TÜV-SÜD. The complete production process with quality assurance, the emission behaviour and the economical use of preservatives are subject to control.

As market leader in shielding inks, YSHIELD has a complete overview of the competitive situation. After all, they want to know where they stand and guarantee that the customer always gets the best products on the market. YSHIELD regularly tests all products in terms of measurement and application technology. For some time now, however, there has been a wild drive to provide incorrect technical information and implausible expert opinions on shielding effectiveness.

The right choice of supplier

In general, it’s quite difficult on the internet to judge a supplier’s integrity based on a website. A hypothetical example: a supplier has a professionally designed website, as his main profession is e.g. web designer. The shielding paints offered on his website might be mixed on a part-time basis as small entrepreneur.

If YSHIELD had samples of it in their laboratory, it would be immediately determined that all physical and chemical parameters are inadequate, up to and including unfitness for use. Legal labelling obligations would not be fulfilled.

Whoever decides on such a product would not have made a particularly good purchase, since even unsuccessful shielding is associated with costs and effort. Such products not only harm the supplier himself, but the entire building biology industry.

Decision guidance

  • re there official certifications, e.g. by TÜV?
  • Are there reports concerning fire behaviour? Naming a norm is often not enough.
  • Are there exact indications concerning added preservative agents for allergic persons?
  • Are there any pictures of the manufacturer? How and where do they produce?

SFERICS® relies on YSHIELD’s HF technology, HF products and quality for both professional and building biology reasons. We visited YSHIELD in person and took a look at the production facilities ourselves.

YSHIELD has high-end measurement technology up to 40 GHz in its own in-house EMF laboratory for daily development and quality assurance. This is because the shielding effectiveness is the most important criterion for a shielding paint.

Shielding paints are more and more often promoted with a shielding attenuation up to 40 dB (99,99%). When tested in their laboratory they often have only a shielding attenuation of 10dB (90%) – that’s factor 1000 less!

Wrong shielding attenuation values

One reason for this might be, that the competitor assumes that his shielding paint shields as well as our shielding paint does, because he thinks there is no difference in the quality of graphite: thus, he uses our indications unaudited. Always ask for a professional measuring done by prestigious experts!

In the past there was yet another reason for that: the client provided an already completely painted sample board to the expert. It was then assumed – without further checks – that the indications concerning material and spreading rate were correct. Frequently the client sent in a sample board that had been secretly painted with several layers and way too thick. With support of PROnatur24®, YSHIELD has revealed this unacceptable situation and have very intense contact to all prestigious experts since that time. That’s why you can trust professional measurements by now.

Sometimes an ‘absorption ratio’ is promoted for shielding paints. YSHIELD has two setups on their premises to measure the absorption capacities of materials: According to IEEE Std 1128-1998 and by 1-port-measurement with a vector network analyser.

There is the general assumption that “metallic” products reflect the pollution, whereas products on “based on carbon” absorb the pollution. YSHIELD has successfully disproved and destroyed this myth about HF absorption.

The lower the electrical resistance, the more will be reflected. The higher the electrical resistance, the more will be absorbed. BUT: a high shielding attenuation (low resistance) conflicts with the needed high resistance for a good absorption.

YSHIELD has measured that shielding paints with a typical shielding attenuation of 40 dB have an absorption of less than 0,01dB at the most. This conflicts with advertising promises of 15% absorption. This value is also quite often only theoretically calculated, with doubtful measured values on the lower end of the frequency range.

Even the new wonder material graphene does not cause an absorption for low resistance shielding paints! After hundreds of material samples, YSHIELD can for sure confirm this fact.