Denver Coleman, Chairman of Polyflor SA, discusses the role of Electro Static Dissipative flooring & when to install it.

With more than 50 years’ experience in the local and international flooring industry, Denver Coleman, Chairman of Polyflor SA, answers questions posed by installers, architects and readers. In this issue, he discusses the role of Electro Static Dissipative (ESD) flooring in specialised environments such as x-ray departments and how to go about achieving a successful ESD installation.

How do I know what flooring to use in my x-ray department? I have been made aware that I will need to use a specialised floor to protect my equipment and I do not have much experience with this. Are you able to assist? Gawie Venter, Pretoria

There are numerous products and installations in our industry that require specialised knowledge and experience.

ESD flooring is a prime example.
There are a variety of ESD products available and no one product can be labelled as the “best”, which is a question often asked by clients and sometimes specifiers. The criteria are simply based on selecting the correct product for the application. This process however, requires extensive professional knowledge and very often, expert advice. Weighing up the technical specification of the product and ensuring it best meets the function and requirement of the area is critical to the process.

There are numerous factors for consideration when sourcing an ESD flooring product. Most importantly is to determine the protection level required in the area. In order to do so, one would need to fully understand the nature of the activity taking place in the area and what needs to be protected i.e. equipment, people, etc. Adjacent areas are often neglected when selecting an ESD floor. Floor surfaces on adjacent areas have a large influence on the amount of static carried into the room being protected as some surfaces are static resistant and tend to transmit static into the protected area. Footwear, door handles and walk off matting are also a consideration as they will also influence the amount of static created within the area. Humidity plays a big role and in areas with high humidity you would require a lower specification as water is an excellent conductor and helps to dissipate the static. You may thus require a lower specification in Durban and a higher one in Johannesburg for the same equipment.

Much of our lives revolve around technology and data safety is critical in many of our lives and businesses. Static accumulation is a factor that cannot be ignored in our technological world. It is a fact that a human will feel a “zap” at about 3 000 volts but it can take as little as five volts to destroy electronic equipment. It is said that 60+% of unexplained computer, notebook, tablet and smart phone faults are likely caused by static.

Applications that call for ESD specialised flooring products include the following:
Computer installations; high end electronic manufacture; military/ordinance manufacture and storage; schools; university and education facilities where advanced electronics now form an integral part of the programme. Static is detrimental to the functioning of the said areas, people and facilities and protection is critical.

To achieve an effective ESD installation, aside from the critical product/specification match, it is imperative that the installer is fully au fait with the specialised installation requirement. This would include using the correct conductive adhesive as well as knowing which type of earthing grid is required; either aluminium, copper or stainless steel strips (stainless steel strips are used for fully conductive installation). The correct earthing method and frequency of earthing points and how best to install them is critically important, and certainly an integral requirement for a successful installation. It is also imperative that an ESD floor is never sealed unless a conductive sealer is used.

Basic ESD flooring category guideline is as follows:
SD (static dissipative with a resistance of 106 – 109 Ohms) Due to its higher resistance reading, SD is generally used for less sensitive areas where computers/tablets are used or computer control rooms, telephone exchanges, schools or businesses where smart/sensitive equipment is used.

EC (Electro static dissipative with a resistance of 104 – 106 Ohms) This product has less resistance than SD and is therefore used in more sensitive areas such as: electronic manufacturing, operating theatres where up rated electronic equipment (Gama Ray) Cat scans, Cath labs, Linear Accelerators are found.

Fully conductive (with a resistance of 0 – 104 Ohms) has very little resistance and allows static to flow away quickly. This level of specification is below the safety threshold for humans being fully conductive (short circuit). So all electric equipment used here should be double insulated, and light switches etc. need to be outside the room or these fixtures need to be flame/flash proof as often used in the mines. This product is mainly used for manufacture of munitions, explosives, hazardous/flammable situations and chemicals.

It is highly recommended that the respective ESD flooring manufacturer is contacted to ensure the product and installation meets the project requirement.

The products available on the market today all serve a purpose and with the right collaboration and expertise, will ensure the ultimate success of the project.