At the MEP UAE Conference 2019, held on 24 April, in a panel that debated on HVAC and indoor air quality (IAQ), Hassan Younes, technical director at Griffin Consultants, asked Jagath Gunawardena, senior manager, projects & building development, Dubai Chamber of Commerce, as to what were the minimum IAQ requirements that needs to be followed by consultants and contractors.
Gunawardena responded: “We have always asked them to follow ASHRAE 62.1, and for smaller buildings, we follow ASHRAE 62.2. We don’t have to re-invent the wheel and we have what we require. We follow demand ventilation. We have lot of CO2 sensors fitted at the sitting level 1.2 meter high from the floor level. It is being monitored. Every six months, we perform IAQ checks as per the SMACNA standards.” Gunawardena added that he has never come across a scenario where he had to incur additional costs when opting for green solutions.
Suhas Inamdar, head of technical support and planning at Wasl Properties, said that IAQ has been something that is “grossly neglected in this region”.
Providing some more statistics, Inamdar revealed: “Indoor pollution is generally two to five times more than outdoor pollution. Moreover, in cars, which we travel every day, it is as high as 15 times. So this is something which is not known.”
According to Inamdar, the worldwide air quality yearly market is around $6bn, and the GCC has only $180m of that share, with the UAE being around $30m. He said: “That shows the importance given to IAQ in this region.”
He said that the connection between air-conditioning and IAQ is in two areas: one is how much of the air is being re-circulated and second is how much of fresh air is being added into this. Inamdar said: “From a facilities management perspective, the design of AC in any building is done primarily based on the cost, and so IAQ ranks very low choosing the right AC.
“I believe that IAQ and AC are strongly independent subjects because there is only an overlap of 20%. IAQ is dependent on several other factors such as the living conditions of person and that is where awareness needs to come into play.”
Elaborating on how IAQ is majorly influenced by the lifestyle of the occupant, Inamdar said: “The kind of items a person has in his house and the way he/she lives. For example, if the tenant is not keeping the house clean, keeps things moist in the house, then he/she is likely to have problems such as moulds. Also, if the tenant has pets in the house, then definitely there will be IAQ issues.
“As a landlord, our role is very limited as how far we can intrude into the privacy of the tenant and maintain the IAQ. So we don’t have any strict measures. We do checks on a case-to-case basis.”
Bringing a manufacturer’s and a technical perspective is Utpal Joshi, head – VRV Dx consulting sales, Daikin Middle East. On the technologies recommended to building owners, he said: “One good thing is that there are regulations for buildings. We need to have treated fresh air. So this is one good thing that we are not wasting energy. However, so main part remains in the treatment of air because in summer we have 46 degrees C and we treat them. And how we recover that is also very important.
“The other big issue is approval is given on 34 degrees C dry bulb/32 degrees C as wet bulb on winter load for FAHU, and that means you are oversizing the coils. In a building, fresh air handling units (FAHU) would have cost 40% of the energy bill. The largest bill comes from a single item which is FAHU for your IAQ. Sometimes people turn it off in a private building.”
He said that the solutions are to increase the energy efficiency of FAHU through variable technologies. Joshi said: “For chillers, you go with inverter chillers or VRV technology and not with DX technology. So your initial cost is high but your running cost is low, so this is one way of looking at it.” He added the demand ventilation is the right way of doing things. From a maintenance perspective, he said that every FAHUs have a sliding filter, and that panel filter is ideal. He said: “We provide a lot of awareness to the consultants and owners so that things are done the right way.”
Gunawardena said that at times he has had to go against regulations to have good IAQ. Giving an example: “When we did the University of Dubai building. One thing required by the green building [regulation] was operable windows. We said you cannot have operable windows in a building like this because students will keep it open and then you can’t manage the IAQ. I hope they will change this regulation. In our University of Dubai project, we opted to pay the fine to not have operable windows.”
Joshi said that it all should start at the commissioning stage. He said: “If commissioning [of buildings] is done perfectly, the half of the issues can be solved. It needs to be done right the first time. Our commissioning of buildings must be regulated in some way. When you are first giving away the building, it should be approved in terms of IAQ.”