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The Cinderella treatment of Cx, RCx

Commissioning (Cx) and retro-commissioning (RCx) do not come for discussion in the design, delivery and the eventual operation of many new construction and existing buildings, says Ian Fail-Brown, adding that their avoidance directly impacts energy efficiency, reliability and IAQ

  • by CCME Content Team |
  • Published: April 9, 2021
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The last two years have undoubtedly had an effect on the construction industry, and dependent upon your position in the supply chain, your views on the way forward may differ. It is clear, however, that with the greater emphasis being given to the criticality of the overall quality of the building performance, it may just be the time when the role of the CxA and the wider MEP T&C community are engaged prior to the initial design being completed and buildings are handed over to clients and operators.

All GCC region nations have published their own version of their Vision for the Future documents, where the overall improvements to indoor and outside spaces designed to improve citizen wellbeing have been clearly stated. Indeed, the region is committed to being the world’s leader in sustainable environmental policies and practices. In order to achieve these worthy goals, we must address the current issues that continue to hold back progress, starting with the simply thorny issue, “Why is the voice of commissioning (Cx) and retro-commissioning (RCx) organisations still being ignored?” It is a legitimate question, because we have so much to offer.

Cx and RCx
Despite the volume of positive cost-effectiveness data now available, CAPEX costs and the unwarranted doubt surrounding actual savings achieved by conducting Cx and RCx on new and existing buildings, developers and building owners are still reluctant from engaging in Cx or RCx activities. Owners, developers often, mistakenly believe that installing efficient equipment is enough, without considering the fact that the equipment may not deliver the specified efficiency if it is not commissioned or poorly adjusted or operated. Owners who have had Cx performed generally do not understand the value – both operationally and commercially – that periodic RCx can deliver.

The intent of Cx is to assure that systems are correctly installed, tested, adjusted and balanced to achieve the highest level of building performance. RCx is the commissioning of existing buildings after they have been in operational use. RCx is performed on buildings that have not been commissioned, and it is sometimes used to “tune up” the existing MEP systems. Often, owners decide to simply recommission specific systems, such as heating, ventilation and air conditioning. Even when initially commissioned, building performance usually degrades over time, leading to greater energy waste, reduced occupant comfort and increased operational maintenance costs. In order to assure long-term high performance, buildings should undergo periodic RCx every five years.

Ian Fail-Brown

Cx of new and RCx of existing buildings is a proven method for improving building energy performance. Building owners and operators can generate an improved occupant satisfaction score, can increase the rental values and increase the value of their assets (property values) while reducing their operational costs. Energy savings for buildings that have undertaken comprehensive Cx or RCx are slated as being between 10% and 20%.

For a new building, Cx is part of a quality assurance (QA) strategy to confirm to owners that systems have been installed correctly and are compliant with specification. Owners and developers benefit from complete QA, which reduces the need to address problems and system failures under warranty, once a building is occupied.

A Lawrence Berkeley National Laboratory study found Cx delivering normalised median energy savings of 13% in new construction and 16% for existing buildings. The normalised median cost of Cx was USD 1.16 per square feet for new buildings (0.4% of construction costs), yielding a 4.2 year payback from energy savings and was USD 0.30 per square feet for existing buildings, yielding a 1.1 year payback.

Importance of Indoor Air Quality
It can be argued that the HVAC systems are the most critical element of any new or refurbished building due to their ability to impact its occupants in a positive or negative manner. It is imperative that systems are tested, balanced and commissioned by trained engineers, as un-commissioned or systems commissioned by un-trained Commissioning Engineers are the potential cause of health issues. Sick Building Syndrome is a relatively new term; however, doctors are diagnosing this more frequently as a cause of illness for many patients in the UAE.

Below is an extract from The National:

ABU DHABI // The environment of workplaces could be damaging workers’ health.

Dozens of office workers visit clinics every month, complaining of headaches, sore throats, itchy eyes, breathing difficulties and skin complaints. These symptoms are related to Sick Building Syndrome (SBS).

SBS is attributed to unhealthy or stressful factors – such as poor ventilation and dust, fungal spores and other airborne particles – at workplaces.

Doctors say employers should invest in better ventilation systems and air quality measures to safeguard the well-being of their staff.

“Sick Building Syndrome is very common in the UAE and other fast-growing countries,” said Dr Trilok Chand, a specialist in respiratory medicine at Burjeel Hospital.

“The reason is often poor ventilation in these buildings, while leaks and other water issues can carry bacterial infections such as fungus.”

He sees about a dozen cases exhibiting respiratory symptoms each month. If a patient has underlying lung problems such as asthma, it worsens their condition.

“Such symptoms are common in my clinic. Patients explain how they feel better once they are outside their work building,” Dr Chand said.

He pointed to air pollution, poor ventilation and the circulation of unclean air as common causes of workplace-related illness. SBS coupled with heavy workloads, long periods on the computer and stressful environments hurt productivity, Dr Chand said.

Dr Lakshmi Chembolli, a dermatologist at Medeor Medical Centre, said SBS was relevant to the UAE.

Typical pollutants of concern include:
• Combustion by-products, such as carbon monoxide, particulate matter, and environmental tobacco smoke
• Substances of natural origin, such as radon, pet dander and mould
• Biological agents such as moulds
• Pesticides, lead and asbestos

Effects on human health
Health effects associated with poor indoor air quality include:

• Irritation of the eyes, nose and throat
• Headaches, dizziness and fatigue
• Respiratory diseases, heart disease and cancer

The link between some common indoor air pollutants – to cite some examples, radon, particle pollution, carbon monoxide, Legionella bacterium – and health effects is very well established.

• Radon is a known human carcinogen and is the second leading cause of lung cancer.
• Carbon monoxide is toxic, and short-term exposure to elevated carbon monoxide levels in indoor settings can be lethal.
• Episodes of Legionnaires’ disease, a form of pneumonia, caused by exposure to the Legionella bacterium, have been associated with buildings with poorly maintained air conditioning or heating systems.
• Numerous indoor air pollutants – dust mites, mould, pet dander, environmental tobacco smoke, cockroach allergens, particulate matter, and others – are “asthma triggers”, meaning that some asthmatics might experience asthma attacks following exposure.

While adverse health effects have been attributed to pollutants, the understanding of some indoor air quality issues continues to improve.

Researchers also have been investigating the relationship between indoor air quality and other issues not previously thought of as related to health, such as employee performance and productivity in occupational settings. Whilst this is relatively new, the current available data suggest employees who work in buildings that have HVAC systems that have been fully commissioned and are delivering higher air quality are more productive and have less time off with illness.

Conclusion
Well designed, maintained and commissioned HVAC systems will be central in taking the first steps towards delivering buildings that keep indoor air quality as a driver to improving the general wellbeing of all who operate within that specific space. A healthy building is determined as a space that improves the mental, social and physical well-being of its occupants.

The HVAC system of a building is the single most important driving force of indoor air quality. HVAC systems can act as a source of pollutants if improper materials are used; specifically, the accumulation of dust and high humidity can lead to fungal growth in ductwork systems, which ultimately reduces indoor air quality.

With Covid-19 and the associated lockdowns, people are spending more time indoors, and with the growing trend of working from home, which appears to be to a great extent here to stay, the requirement for buildings to be effective, efficient and safe spaces is increasing exponentially; and HVAC systems are at the centre of our abilities to deliver these. Without the added value of Cx and RCx delivering fully functioning, compliant, healthy buildings, the possible health and commercial benefits are lost.

We all have an obligation to create buildings that are effective, efficient and are safe spaces to work, live and play, both for today and for the future. To achieve this, we need to embrace the benefits of Cx and RCx and fully understand the risks we are creating when we choose not to.

 

The writer is CEO, SESC Project Management and Committee Member, CSA (Commissioning Specialists Association), GCC region. He may be contacted at irfail.brown@sescgroup.ae.

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