Good elasticity products

<The following is the list of things to check to

choose the right elastic flooring material>


10 checklist items that need to be considered when choosing elastic products such as rubber block mat

1. 10 checklist items that need to be considered when choosing elastic products such as rubber block mat




How to Check


Is the manufacturer reliable?

Credit Rating of Plubber BBB-

You can click the product advertised online over official mall websites to check the seller’s credit ratings and other product details


Is the product certified according to relevant standards?

Plubber’s rubber block mat is certified as environmental friendly and compliant to designated plant procedures.

Must check whether the manufacturer has been certified via plant procedure checks according to quality and safety management law and via KS, environmental mark etc.


Is the material being used (rubber chip) consistent?

Plubber gets test certificate every six months from Korea Testing and Research Institute.

whether test certificates and regular tests are being proceeded according to the “recycled rubber powder quality standards” announced by Korean Industrial Standards


Is the material being used (rubber chip) consistent?

Plubber uses recycled rubber chips for tire chips and directly-produced rubber chips for new EPDM rubber chips only respectively.

New-material based rubber chips must be checked whether they are produced separately as well as their country of origin; recycled rubber chips need to be checked whether the origin is the same (rubber chips excluding tire chips and imported rubber chips are difficult to be verified for its harmfulness due to their inconsistency)


Is the product durable and weather-proof?

Plubber sets standard weight for each product and releases only those within the margin of error. It adopts sequential arrangement method for production for durability.

Light and less dense rubber chips are low in durability and can easily be contracted or expanded. The products whose upper part is heated at the lower mold through reverse arrangement have low durability due to weakened property of the surface binder.


Is the product durable?

Plubber produces durable and elastic products through sequential arrangement (for 50T mat, it is the highest at the drop height limit of 1,550mm).

Check the safety check certificate for critical fall height; for some products that are lighter and less dense than others to increase the critical fall height, elasticity test scores and durability details must be compared.


Can the expansion and contraction be adjustable?

Plubber inserts connecting pins at every corner of the product during the application, making the whole space integrated to significantly enhance the structural safety

As elastic-material-based rubber chips tend to contract and expand according to the external factors, connecting pins that can connect the products without creating irregular gaps must be checked for inter-locking products.


Is the product stable color-wise?

Plubber, a company with product labs and UV tester, conducts continuous color stability test under room temperature and at the lab.

Continuous test records should be based to determine production and application as rubber block mat and elastic surfacing material have low color stability due to binder, coloring agent and temperature outside etc.


Is the product easy to apply, repair and maintain

Plubber can easily retain the consistency of the product quality and repair & fix as we only sell and apply directly-manufactured material and products.

Using those bought outside instead of using our own products can create difficulty in repair as their properties and quality are not controlled under one controller. As for rubber block mat, inter-locking method is easier for repair and maintenance than elastic surfacing.


Is it economical and eco-friendly, including the civil engineering construction?

Rubber block mats can be applied right onto the sands so comparatively the civil construction cost is low and the process is eco-friendly.

As for elastic surfacing, the construction fee is high, the duration is long and the water might not be able to flow as it is built on the concrete most of the time.

2. Make sure that you have the manufacturer’s credit ratings, the plant, product certification and other quality-related certification.

2. Make sure that you have the manufacturer’s credit ratings, the plant, product certification and other quality-related certification.


Most of the robber block mats or elastic surfacing experts are registered in the supply chain registration initiated by Korea Public Procurement Service. In order to register into the system, the applicant must submit the credit ratings report issued by the official credit rating institute to the Service. Enter “rubber block”, “rubber mat” or “elastic surfacing”, the companies into the search box of and the products registered in the Service can be searched for each category via ( You can click for further information along with product details and corporate credit ratings level. Plubber, a BBB- credit rating company, topped the list in rubber blocks and mats and earned top five level of recognition for its technology in elastic surfacing. As one of the finest venture startups (recognized by Small & Medium Business Agency), parts and material experts (by Ministry of Knowledge and Economy) and Inno-Biz (recognized by Korea Technology Finance Corporation), we have been gaining trust from major governmental bodies including Korea Public Procurement Service.

3. Make sure to check the material and the product whether they are harmless to human body through inspection

3. Make sure to check the material and the product whether they are harmless to human body through inspection


The rubber chips used as flooring elastic material is recycled material using tires except new-EPDM rubber chips or new urethane chips. The product quality can be maintained consistently only if the recycled natural ingredients need to be consistent too. Even if their material is recycled, it would negatively affect the final product if all materials without clear source of origin are haphazardly combined. So in order to create good recycled products, it is critical to maintain consistency for such recycled materials. As we utilize recycled material, it must be clear that the material and the product have both passed Harmfulness Verification tests. The main standards for the rubber chip designated by Korea Industrial Standard.


<Quality Standards on EPDM>


Note 1: T-VOC2 consists of benzene, toluene, XXX, XXX. As for benzene, the threshold amount is 1mg/kg or less.

Note 2: PAHs is a benzene series chemicals consisting of aromatic links harmful to human body. It is the total weight of XXX, XXX, XXX, XXX. However, the threshold amount of Benzo(a)oyrene should be below 1ppm according to the international standards since Jan. 2010.


4. Make sure to check material (rubber chip), whether they are directly produced and the country of origin.

4. Make sure to check material (rubber chip), whether they are directly produced and the country of origin


Rubber block mats and rubber chips used for elastic surfacing are mostly those recycled from old tires. For recycled ones, it is crucial to get them verified according to origins and types to ensure quality and consistency. For those not manufactured directly, they need more than just a simple test certificate to determine whether they contain harmful substances or not. Plubber conducts thorough inspection to verify harmfulness of those materials according to their origins and types in advance to decide whether those recycled can be used at all.

The EPDM color rubber chips, main component of rubber block mat and elastic surfacing material, are subject to the marking of the country of origin. Many of the rubber block mat and EPDM color rubber chips distributed in the domestic market are made in China yet many consumers are not aware of the fact. There is no reason not to mark the country of origin if their quality and safety is assured, right? Those violated the rule of marking the country of origin may be considered smuggled. Some unscrupulous operators import the material, chop them in pieces or repack them here in Korea and argue that they are made in Korea thus no need for the marking of the country of origin. However, this is very wrong because the regulation says if certain materials are just disassembled and repacked here, their country of origin still needs to be identified. Plubber’s products in the Korean market are all made in Korea without exception.

5. We need to understand correctly about the product’s elasticity and durability.

5. We need to understand correctly about the product’s elasticity and durability


Elasticity is determined by the material’s thickness and its inherent elasticity. The material of rubber can vary in its elasticity according to its types and properties such as tire chips, EPDM chips and others, so what rubber chips you used can make a huge difference in the product’s elasticity. To enhance the elasticity, it is important to use lighter, highly elastic rubber chip and the thickness of those chips also matters. According to the research by our lab, the best elastic rubber chip for surfacing and flooring such as rubber block mat is the tire rubber chip and among its kind, tire rubber chips for trucks and buses are the best as they contain highest level of natural rubber. The elasticity increases in proportion with the thickness until 100mm but 75mm is the threshold where the increase gets far less exponential, meaning it is ineffective. So our company manufactures and applies those with thickness of 75mm or thinner.


Durability is determined by the light, density, combining force, and the production method considering the raw material properties. In other words, if the product is light and the chip density is low, the combining force will be low and the contraction-expansion can be more fluctuating. Therefore, Plubber sets standard weight for each product model and sells only those that fall within the range of margin of error for that weight.


Plubber also uses very different sequential arrangement production method from other peer manufacturers to enhance the durability of the block mat. The sequential arrangement production method puts the rubber chip which supports the lower base part first and then the upper color part later which determines durability when pouring rubber chips and binder-mixed material into the mold. The polyurethane binder gets hardened when heated so if you put upper color chip right before the mold is pressed, the mixed binder on the upper color chip can maintain its properties for a long period. This ensures higher durability for the upper part and higher elasticity for the lower part. As a result, Plubber products are durable and have a high standard of 50T mat and gets safety inspection certification of 1,550mm, highest level in Korea.


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Those with less durability and less weight have high cushioning so you can often experience peeling off of the surface or the edge. If you rub the edge of the rubber block mat hard and its surface gets peeled off, you can say it is less durable. (of course there are some consumers who like such rubber chips because they have high elasticity). However, most of those rubber blocks are applied in India, which makes it more important to provide products with better durability rather than better elasticity. As for rubber mats, durability would be the priority except the usage is for kids’ play house, which requires more elasticity. Some unscrupulous manufacturers and importers provide cushy products by reducing the content of rubber chips and binder (adhesive) into the product. However such cushioning effect is temporary and the product will become inherently weak by far and of poor quality. In some of kids’ playgrounds or houses, the rubber mats are so weak and the high heels of women walking over the mat creates dent in those rubber chips. Those importers argue that it has to be that way because you have to sacrifice certain level of durability in order to get higher elasticity but it is not true. Products should be equipped with at least a certain level of durability and then the elasticity should be considered.

6.Understanding the quality of rubber block mat

6. Understanding the quality of rubber block mat


Rubber block mats are basically made of elastic rubber chips so they can contract or expand according to the temperature outside. According to the KS standards, the margin of lengths of ±2mm and the thickness of ±1mm are considered normal range for a product of 220(L)*110(W)*45(T). For lot products for application, the discrepancy can be as much as 4mm for the length and 2mm for the thickness. But as most of the rubber block mats are applied on the sand, a neat and meticulous application can cover such discrepancies.


One of the most common problems for the elastic materials is the bending of its edges. This can be caused by either rubber chip or binder. As for the bending that occurs due to the rubber chip, it is caused because the two different rubber chips at the colored upper part and the black chip under it contact and expand much differently according to the outside conditions. For those already applied and in use, people tend to use and step on the center the most, which caves in at the center due to the concentrated force, bending the flanks on each side. This can be seen most commonly in mats placed under the slides or swings in the kids’ playground.

As for the bending with the binder, the polyurethane-base binder contracts and expands due to heat, which explains why the bending occurs in scorching summers. In such cases, they return to their original form at the change of season or at dawn when the temperature gets lower. Still, the bending is one of the weaknesses of elastic materials so the replacement material that can overcome such problem must be developed. Plubber produces Combi products which connects four mats in one with connecting pins at the four corners to overcome bending. The application of these combi products integrates the whole area with connecting pins, ensuring high structural stability.

As such, the rubber block mat is made of elastic materials and so has some of its own weaknesses but its water permeability and elasticity are so great, which makes the product worthwhile and useful compared to concrete blocks or other flooring materials.

Some consumers complain that rubber block mat sometimes gets washed off in heavy rain unlike concrete blocks and that it gets disconnected when the sand ground is versatile due to its water permeability. However such arguments only compare the superficial features of rubber block mats against other flooring material. Rubber is heavier than the water so they just cannot get washed away in rain and in extremely heavy rain maybe the concrete blocks too can get washed away. The complaint about the disconnection due to versatile sand ground is also misplaced. Considering the high quality of water permeability, such disconnection is most likely to be from bad construction application regarding the drainage rather than the product itself. Such application mishaps are easily witnessed in construction sites using concrete blocks as well.

7. Difference between plant-produced “rubber block mat” and “elastic surfacing application” on-site”의 차이

7. Difference between plant-produced “rubber block mat” and “elastic surfacing application” on-site


Plant-produced rubber blocks or mats are molded under the heat 130~150℃ and pressed by the press heavier than 150 tons for more than 20 minutes. However, the elastic surfacing on-site involves rubber chips and binder (adhesives) mixing on site and applying on the floor with a heat roller as hot as 100℃ that presses, smoothes out and paves.

In order to address the problem of low durability compared to plant-produced rubber block mat, binder should be put more by three to five times compared to the rubber block mats above. Still, the tension strength is less than 50% that of the plant-produced rubber mat. Putting more binder means higher cost and price, making them two to three times more expensive per thickness. On-site application is done without creating any seams like Ascon or concrete and unlike rubber block mats so once you get a flaw or damage, it can be extended to wider area, making it difficult for an effective repair. And even if you respond to those flaws, it leaves trail behind, possibly making it a bit ugly and in worse cases such as a need for sewage reconstruction, the whole area of the application should be removed and redone.

Another weakness of on-site elastic application is that it is usually applied on the concrete, preventing the water permeability so they need to get out on the surface. As a result, the water resource that should go back to the underground is lost to the sewage. In some cases, in order to ensure a certain level of water permeability, operators mix Ascon and rubber chips for thick (min, 50mm thick) complex multi-layered surfacing and apply color elastic rubber chip on top. According to Plubber’s research results, however, such application is very accident-prone such as underground sinking so we do not adopt such application method.


Surfacing on site can have some benefits as well: it can create very aesthetic surface and detailed paintings and designs, helping make the cityscape all the more beautiful. On the other hand, rubber block mats are more likely to create a certain regular patterns via interlocking rather than beautiful details. The seams on the surface make it easier for the block mats to be separated or disconnected if the application is done haphazardly.

At the end of the day, which to choose either the rubber block mat or the elastic flooring on site boils down to considering all the factors including the purpose of the site, budget, application, cityscape, practicality, economicality etc. For golf courses for example, on-site elastic surfacing can be more effective as the arena requires neat view. For crowded pedestrian path, maybe rubber block mats can be more effective considering maintenance problem and need for a simple application etc.

8. Difference between Urethane chip and EPDM rubber chip used for elastic surfacing.


8. Difference between Urethane chip and EPDM rubber chip used for elastic surfacing


Basically EPDM chips and urethane chips are hard to tell from one another so often they burn the chips to verify. EPDM chips create white smoke or none and leave ashes after complete combustion. Urethane chips on the other hand create black smoke and boils and melts down.

Urethane chips are made by mixing liquid urethane, filler and agent and hardening the mixture and grinding it. Regenerative urethane chip on the other hand is made by melting the urethane scraps into liquid and then on the same procedure as new urethane chip. As a result, it is virtually very difficult to tell the difference between the two, allowing some sellers to confuse the two unwittingly or intentionally and deceive consumers.

As for urethane scraps, main component of the regenerative urethane, the biggest provider is the shoe factories. However many of Korea’s shoe factories have relocated to the third country, allowing more of those scraps to be imported. The new urethane chips are rather expensive compared to the EPDM chips. Mostly comparing the properties of the products from different lots is used to tell the difference between these different chips. Regenerative urethane chips show irregular properties and features as they combine various scraps unlike the homogenous feature of the new urethane chip. As such, regenerative urethane chips need to be inspected lot per lot for heavy metals or other harmful chemicals to human body.

Urethane chips require way more binder than EPDM chips in on-site elastic surfacing to get the intended tension. So at a glance, the regenerative urethane chips may look cheaper but considering the binder that is needed, the total cost is almost the same. EPDM chip application would be rather preferred because it gets cheaper all in all.

9. Difference in application on the concrete and on the sand

9. Difference in application on the concrete and on the sand


Rubber mats and elastic surfacing materials applied on kids’ playground must be inspected for installation these days. Considering the critical fall height, elastic surfacing is rather preferred that boasts high elasticity but with less durability. According to our test report (Korea Conformity Laboratories) on critical fall height of 50mm-thick product, our rubber mat product scored 1,550mm and peer on-site surfacing product scored 1,615mm, slightly higher. However our products can be applied on the sand, which adds about 300mm so this satisfies both the durability and elasticity better than on-site surfacing material with lower product price and construction cost as it requires no concrete surfacing work.

Application on the concrete will remove the very strength of the rubber block mat, the water permeability. Also the thermal heat during the summer can directly be delivered from the heated ground to the rubber mat. However, concrete application has its perks. As it is applied with binder to adhere to the concrete, there is little risk of ground sinking, ensuring to preserve the application as is for long time.

10. A thought on the harmfulness of the recycled rubber chip.

10. A thought on the harmfulness of the recycled rubber chip


A media outlet released some news in December 2006 that the recycled tire chips used as fillers in the artificial grass emitted harmful chemicals to the human body. Due to that incident, recycled tire chips were banned and regenerative EPDM chips were enormously imported from China. They were also used as filler for artificial grass at the school lawns supported by Korea’s Education Ministry.

We at Plubber were a bit confused with the news. We are a company producing products based on recycled rubber chips. If those chips all have harmful substances, then all the fine dust created by the friction between the road and the tires of the vehicles running as of now on the roads of the Earth should carry such harmful substances, right? If so, the concern should first address the product of tire itself, then I thought.

Recycled tire rubber chips are made from old tires removed from steel bars inside and ground in different chip shape. We just could not understand as they only go through physical changes without putting any chemical additives, which makes it all the more groundless the argument that the tires are okay but the chips that are made of chopped tires are not okay. If the chips are harmful, that means all the tires on the move on the roads are harmful too. Still, parents raised concerns about the harmfulness of the chips and the Ministry of Education set the “threshold for harmful substances contained in recycled rubber powder”. Between May and July 2007, a wide inspection was conducted over the existing artificial grass sports arenas whether the filler rubber chips used were safe and 43 schools out of 176 inspected (24.4%) were found to have rubber chips that exceeds the threshold regulation. They were all EPDM chips of unclear origin and imported Chinese tire chips, and tire chips made in Korea violated none of the standards set by the Ministry.

Though the inspection was right thing to do, we believe the news may be quite misleading because it can make people misunderstand that all rubber chips are toxic. As for such concerns, we do have multiple research report that rubber chips are not harmful issued from advanced nations that use rubber block mat or grass filler a lot, so please feel free to contact us for the report.

Companies using recycled goods should take extra caution to ensure consumer safety such as detecting harmful substances and quality control with a perception that they are using wastes to make products. Consumers should also think that products made of recycled goods are practically new so as to boost the recycle industry. I remember being surprised at a house garden in the U.S. because the children had some tire chips lying around that can be in contact with the children. They said that it is okay because they have passed all the safety tests and are on a continuous path for regular checkups. Thinking about how parents would react if they saw those tire chips instead of the sand in their children’s playground. I had to think about how to rectify the current situation as well as people’s misunderstanding about the environment, the safety and the recycling.

Plubber only uses old tires made in Korea to make our tire chips to ensure the quality and safety. It is a KS-certified company that conducts meticulous and strict inspection and quality control from the material entry to final product. We ensure that we verify whether all materials are safe and free of harmful chemicals and have adequate quality.