Aluminum, black steel, acid-resistant steel. Each of these metals has different properties, a degree of corrosion resistance, and therefore a price. The situation is similar with plastics, and in the case of a “flexible” spill containment berm – with a technical fabric coating. Find out what are the main types of technical fabrics used in secondary berms and learn about their differences.

PVC, EVA, or maybe TPU? Learn about the differences in the construction of spill containment berms

PVC, EVA, or maybe TPU Learn about the differences in the construction of spill containment berms

Aluminum, black steel, acid-resistant steel. Each of these metals has different properties, a degree of corrosion resistance, and therefore a price. The situation is similar with materials, and in the case of a “flexible” spill containment berm – with the coating of the technical fabric from which it is made. Knowing what the secondary berm is made of will allow you to estimate its durability and the level of safety it will provide over the next years of use.

From this article you will learn:

  • What are the main technical lines in spill containment berms in the world?
  • What are the differences in chemical insulation = secondary berm
  • additional coatings on the spill containment berm

Technical fabrics: what can your secondary berm be made of?

The technical fabric is composed of the so-called “carrier”, most often made of a weave of polyester fibers, which most often has a multi-layer coating (“coating”) applied on both sides, usually consisting of the main polymer and additives.

The illustration below shows the structure of a multi-layer technical fabric:

  1. Polyester carrier with high tensile strength
  2. Double-sided impregnating layer
  3. Double-sided main shell made of the highest quality PVC
  4. Double-sided binding primer
  5. A layer of topcoat
Multi-layer elastic fabric

Multi-layer elastic fabric

The three most common polymers in technical fabric coatings are:

  • PVC (Polyvinyl chloride)
  • EVA (Ethylene-vinyl acetate)
  • TPU (Thermoplastic polyurethane)

Each polymer has its own characteristics and resistance to short and long-term contact with UV radiation, hydrocarbons, acids and bases. Based on resistance tables and materials provided by our European suppliers (reputable companies from the technical fabrics industry) and our own experience, we have created the table below.

Technical fabrics – comparison table for use with spillage tanks:

Fabric description $ $$$ $$$$$
Price +++ ++ ++
Resistance: UV time-limited high high
Resistance: diesel good high high
Resistance: engine oil non-resistant* good – limited high
Resistance: gasoline non-resistant* high high
Resistance: glycol 100% non-resistant* high good
Resistance: undenatured ethanol non-resistant* high high
Resistance: formic acid 50% non-resistant* high no data
Comments: *the substance works
destructively to the coating

Source of data on resistance: technical data sheets and a list of certified suppliers of Exflo technical fabrics, own compilation.

Comparison of PVC, EVA and TPU fabrics

PVC fabric

PVC coating is a cheaper alternative if you do not store hazardous substances. The larger the secondary berm surface, the more you will save on purchase. However, carefully study the list of substances that, after a leak, can affect the berm covering and even destroy it (which makes the spill containment berm practically disposable, especially substances from the table with the “non-resistant” classification).
1-Vinyl-chloride_Polyvinyl-chloride-1 (PVC fabric)

EVA fabric

The Ethylene/Vinyl Acetate polymer used for technical fabrics has significantly greater chemical resistance than standard PVC. This allows you to create collection tanks that are resistant to a number of acids, hydrocarbons and other substances often used in industry. Additionally, it is easier to obtain surface resistance and antistatic properties, which also affects safety. As a component, it is several times more expensive than PVC fabric, which translates into the price of the final product. If in the resistance table of this coating, for the substance you are looking for, you find a resistance symbol of at least “good or limited”, it means that it is resistant to constant contact with liquid, lasting up to several months.
3-Czasteczka-diizocyjanianu-metylenu (EVA fabric)

TPU fabric

Highly resistant technical fabric, especially to hydrocarbons and acids. Resistance to diesel fuel and gasoline can be measured in years. However, the rare use of secondary berm is related to the price, which is several times higher than EVA

Example polyurethane structure:
2-Ethylene-vinyl-acetate (TPU fabric)

Is fabric coating all you need to pay attention to?

In terms of materials, you need to pay attention to two aspects:

  1. coating: remember to choose a coating (PVC, EVA, TPU or possibly a mixed type, the so-called “blend”) that will be resistant to substances stored in the berm. It is important that the investment lasts for a long time and that in the event of the first leak it does not lose the warranty.
  2. thickness / basis weight: basis weight, i.e. density (in grams) per square meter, translates into the thickness of the fabric, which in turn translates into mechanical strength. From our experience, the grammage should be at least 1000g/m2. The higher grammage (1200-1400 g/m2) guarantees many years of use when the trolleys are used frequently (several – several times a day) on the bottom of the spill containment berm.

The colors of all three fabrics may even be identical, which can be confusing for the buyer at first glance (e.g. a black berm is available in both PVC and EVA). It is worth asking the seller what material the spill containment berm is made of and what the fabric weight is. Thanks to this information, you can reliably compare offers from several suppliers and choose the best option.

If you are looking for spill containment berms made of the above fabrics, you will also find them in the Exflo offer:

Find out more about spill containment berms and visit our product page.


Przemysław Domagalski

CEO of Exflo Sp. z o.o.. Regular participant of training and workshops on the storage of hazardous substances and conferences on fire protection. Certified ISO 14001 internal auditor, co-creator of practical products supporting environmental protection, logistics and fire protection.