“Anti-bacterial coatings unnecessary for fabric ducts”, say industry experts. Story: Naveena Sadasivam.

Fabric ducts are slowly making their way into local supermarkets and food refrigeration units as the advantages like hygiene and ease of installation outweigh initial costs. Although they are not commonly used in the Middle East, they have recently gained recognition, especially in the food and pharmaceutical industry, as an alternative to traditional ducting systems since these fields require high levels of hygiene and sanitation.

Speaking about the importance of fabric ducts, Raj Kumar, CEO of Bestpro, stated that antimicrobial coatings are not necessarily required for all fabric ducts used in the food industry. “It defeats the purpose of washability of the fabric”, he said.

Permeability of the fabric, ability to withstand static pressure and fire resistance are all important factors in determining the type of fabric duct to be used for a specific application. In the food industry, however, antimicrobial properties are of the highest importance. In this regard, coating the duct with additional layers to repel germs can prove to be disadvantageous, since frequent washings are required. With time, these coatings will disappear and the integrity of the fabric will be lost. Kumar argued that the natural fibre used to produce these ducts has certain inherent antimicrobial properties that cannot be washed away.

Tawfiq Al Attari, MENA technical director of DuctSox, a US-based manufacturer of air dispersion systems, also holds similar views: “We don’t use antimicrobial coating because, when the customer washes the duct, the coating will be removed from the fabric. Instead, we add an antimicrobial agent during the process of making the threads of the fabric, which makes it long-lasting.”

This idea seems to be working for Barakat Fruits and Vegetables, which has been using fabric ducts at its refrigeration and cooling facilities since it was first opened in 2002. Rakesh Kumar, technical manager at Barakat, informed Climate Control Middle East that they currently wash their canvas and cloth fabric ducts once every three weeks. They also conduct a swab test before and after the wash to monitor the microbial content. “If the amount of humidity is higher in the room, the frequency of cleaning also increases because of the dirt accumulation caused by moisture”, he said.

When asked to compare traditional ducting systems with fabric ducts, Kumar explained that although initial costs are on the higher side, these ducts have a longer life cycle and are more hygienic as long as they are cleaned and maintained properly. Advantages such as these are persuading supermarket chains like Spinneys, Lulu and Carrefour to take notice.

Carrefour has recently installed fabric ducts in many of its outlets in Southeast Asia and is employing this model in its Safeer Mall branch in Fujairah, UAE, which is currently under construction.

In relation to the shift towards fabric ducts, Santhosh Kothenath, Project Manager for Dubai and Northern Emirates at Lulu, claimed that the management is aware of this shift and has been studying the system. “It is a new technology and we do not want to jump into it without considering all the risks and benefits involved”, he said.

He added that they were currently facing pressure from their suppliers in the US and Europe to implement fabric ducting. “We have been contacted by a few suppliers”, he acknowledged. “One of the main reasons for our hesitancy is that the ducts [supplied by those] are fabricated in China which makes us question the quality of the product.”

Marian Han, Business Development Executive at Bestpro agreed that customers’ mindset was a major factor in developing the client base. “Although the fabric itself is made in the US, we face a kind of psychological resistance from customers because the duct is stitched in China. This is despite the fact that our products meet US, European and Chinese standards”, she said. Additionally, Han disclosed that CFD (Computational Fluid Dynamics) models were useful in persuading potential clients to use fabric ducts as the software can simulate velocity and temperature profiles prior to installation.

Moreover, she explained that local technical support is a key factor in ensuring the effective installation and use of fabric ducts. “Engineering support is required to analyse the situational needs of the client and then accordingly design the duct to suit the space”, she said.

Han also highlighted other advantages of fabric ducts including reduced installation time. “A typical hypermarket can have a fabric duct system installed in about ten days, whereas a traditional metal duct system would take around a month of installation work”, she said. Furthermore, conventional ductwork includes insulation materials, acoustic liners, diffusers and sealants. With fabric ducts, these additional elements are not required.

“There has been a big change in the market”, DuctSox’s Attari emphasised. He added: “Consultants now already have prior knowledge about our products which was not the case five years ago.”

Completion of mega projects like the New Doha International Airport, Dubai Duty Free’s warehouses, and Abu Dhabi National Exhibition Centre (ADNEC) has encouraged the company’s consultants and clients to use its fabric ducts, he claimed.

Within the food industry, Attari pointed out that, despite completing installation in international food production companies like Nestle and Kraft, many local manufacturers are unaware of the advantages of DuctSox’s systems. “We are working on this issue by conducting seminars and visiting factories to increase their knowledge and trust in our products”, he said.

Attari and Han both stated that gaining the customer’s trust was proving difficult in the region. While Han referred to local preset notions about Chinese products, Attari referred to the clients’ previous experiences with counterfeit ducts. “We do face distrust because some clients have used counterfeit ducts in the past, which ultimately fail due to tearing or bad design. In such a case, we need to start from ground zero and show them the difference between our products and imitation goods”, he said.