If you want to improve the indoor air quality and energy efficiency of your home or business, you might want to consider installing a mechanical ventilation system. The most optimal ventilation strategy today is with a ‘balanced’ ventilation system. It is superior to exhaust-only or supply-only strategies because it does not affect the pressure of a building. Some building codes and authorities require that the ventilation be balanced due to the strict airtightness standards of building exteriors. The negative or positive pressure in your building can also create drafts, moisture problems and operational issues with certain combustion appliances.

As such, two main types of ventilation systems can provide continuous and predictable air exchange, while recovering some of the heat or energy in the process: HRV (heat recovery ventilator) and ERV (energy recovery ventilator).

What is the difference between HRV and ERV?

The main difference between these two systems is that HRV recovers only heat from the outgoing air, while ERV recovers both heat and moisture. This means that HRV can help reduce heating costs and prevent moisture problems in your home, while ERV can help maintain a comfortable humidity level and reduce cooling costs. The choice between HRV and ERV depends on your local climate, your heating system, your ventilation needs and your budget.

How does an HRV work?

An HRV is a system that uses the heat in stale exhaust air to preheat incoming fresh air. This reduces the energy required to bring outside air up to ambient room temperature, so you save money on heating bills. An HRV also helps prevent condensation and moisture problems in your home by exhausting humid air from bathrooms, kitchens, and laundry rooms.

A typical HRV consists of two fans: one that draws in fresh air and one that expels stale air; and a heat exchanger that transfers heat between the two air streams. The heat exchanger is usually made of metal or plastic plates that are separated by a small gap. The two air streams pass through the plates without mixing, but exchange heat through convection: similar to a car radiator.

Source: NRC 2019

How does an ERV work?

An ERV has the same components as an HRV, but the heat exchanger is different. Instead of metal or plastic plates, an ERV uses a synthetic membrane or a desiccant wheel that allows moisture and energy to pass through, but not air. The membrane or wheel rotates between the two air streams, absorbing moisture and energy from one side and releasing it to the other. This means that an ERV can help maintain a comfortable humidity level in your home, as well as reduce the cooling load in summer. An ERV can also filter out some of the pollutants and allergens from the outdoor air, such as dust, pollen, and smog.

How to save costs with an HRV or an ERV?

Whether you choose an HRV or an ERV, there are some ways to save cost and energy in designing, installing, and operating your ventilation system:

• Choose a system that is ENERGY STAR® certified. This means that the system meets high standards of performance and efficiency. You can also check the ratings of different systems on HVI, which is an independent organization that tests and certifies ventilation products.
• Choose a system that matches the size and layout of your home. A system that is too small or too large will not provide adequate ventilation or will waste energy. You can consult a professional contractor or an engineer to help you determine the optimal size and design of your system.
• Choose a system that has variable speed fans and controls. This allows you to adjust the ventilation rate according to your needs and preferences. You can also use timers, sensors, or smart thermostats to automate the operation of your system and optimize its efficiency.
• Choose a system that has good filters and seals. This ensures that the system does not leak air or lose heat or energy. You should also clean and replace the filters regularly, according to the manufacturer’s instructions.
• Choose a system that has a defrost cycle. This prevents the heat exchanger from freezing in cold weather, which can damage the system or reduce its efficiency. The defrost cycle should be automatic and energy efficient.

Latest Products and Technologies

The technology of HRV and ERV is constantly evolving, and there are new products and techniques that can enhance the performance and functionality of your ventilation system:

• Some systems have integrated heating or cooling coils that can further modify the temperature of the incoming air, depending on your needs. For example, you can use a heat pump to boost the heating or cooling capacity of your ERV.
• Integrated Filtration Systems: Many HRV and ERV systems now come equipped with advanced filtration systems that can capture a wide range of airborne contaminants, including dust, pollen, allergens, and pathogens. Some models even feature HEPA filters or UV-C sterilization to provide cleaner and healthier indoor air.
• Compact and Space-Saving Designs: Manufacturers have been developing more compact and space-saving HRV and ERV systems to accommodate installation in smaller or tighter spaces, such as condos, apartments, and tiny homes. These streamlined designs make it easier to incorporate ventilation systems into a variety of residential and commercial settings.

Conclusion

HRV and ERV are both effective ways to ventilate your home while recovering some of the heat or energy from the outgoing air. The main difference between them is that HRV recovers only heat, while ERV recovers both heat and moisture. The choice between them depends on your local climate, your heating system, your ventilation needs and your budget. You can also save cost and energy by choosing a high-quality system that is properly sized, designed, installed and operated. You can also benefit from some of the latest products and techniques that can enhance the performance and functionality of your ventilation system.

In today’s energy-conscious world, it is crucial to optimize HVAC systems for efficiency and cost savings. Lexus Engineering can help you discover the benefits of energy-saving products and explore different types available. Lexus Engineering will work with you to choose the right products by considering factors like compatibility, energy efficiency ratings, and cost-effectiveness. Learn about installation, maintenance, and troubleshooting to ensure optimal performance. Lexus Engineering can make your HVAC system eco-friendly and wallet-friendly!

Types of Energy Saving Products for HVAC

Exhaust Air Heat Recovery

Exhaust air heat recovery systems transfer heat energy from the exhaust air to the supply air stream, helping reduce the energy consumption for heating or cooling. There are three main types of exhaust air heat recovery systems: rotary, plate, and run-around coils/ heat pipes. Rotary systems transfer sensible and latent heat through a specially designed exchanger design. Plate systems use a fixed heat exchanger that transfers heat by conduction. Run-around coils and heat pipes use a fluid loop that circulates between two coils, transferring heat by conduction, convection, and phase change. Exhaust air heat recovery systems can also be classified as recuperative or regenerative, depending on whether they transfer only sensible heat or both sensible and latent heat. Click here to learn more about the difference between heat recovery and energy recovery.

Energy-Efficient HVAC Units

Heating, ventilation and air conditioning or HVAC is a system that provides comfort and indoor air quality for residential and commercial buildings. Several types of HVAC units vary in their efficiency, cost and suitability for different climates and spaces. Some of the most common types are:

• Heat pumps: Transfer heat from one place to another using a refrigerant cycle. They can provide both heating and cooling by reversing the direction of the cycle. Heat pumps can be air-source or geothermal, depending on whether they use the outside air or the ground as the heat source or sink. Heat pumps are very efficient, especially in mild climates, but they may require a backup heating system in colder regions. The efficiency of heat pumps is measured by HSPF (heating season performance factor) for heating mode and SEER (seasonal energy efficiency ratio) for cooling mode.
• Furnaces: These are systems that burn fuel (such as natural gas, oil, or electricity) to produce heat. The heat is then distributed through ducts and vents to the rooms. Furnaces are widely used in colder climates, but they can be less efficient than heat pumps, especially if they are older models. The efficiency of furnaces is measured by AFUE (annual fuel utilization efficiency), which is the percentage of energy that is converted into heat.
• Air conditioners: Cool the air by removing heat and moisture from it. The cooled air is then circulated through ducts and vents to the rooms. Air conditioners can be split or packaged, depending on whether they have separate indoor and outdoor units or a single unit that contains both components. Air conditioners are essential for hot and humid climates, but they can consume a lot of energy. The efficiency of air conditioners is also measured by SEER.
• Other types: Other types of HVAC units can suit specific needs and preferences, such as variable air volume (VAV), variable refrigerant volume (VRV), fan coil units (FCU) and split cassettes. These systems can offer more flexibility, control and customization for different zones and spaces, but they may also have higher installation and maintenance costs.

Modern HVAC units are designed with advanced technologies that maximize energy efficiency without compromising performance.

Smart Ventilation Systems

Smart ventilation systems are systems which adjust the ventilation rate in a building according to the indoor air quality, energy consumption, and other factors. Smart ventilation systems can provide benefits such as improved comfort, health, and energy efficiency. Smart ventilation systems work with different types of heating and cooling systems, such as central systems, mini splits, window ACs, and more. Smart ventilation systems can be controlled remotely through smart devices or wireless thermostats. Smart ventilation systems are becoming more popular in both residential and commercial buildings as a way to optimize the indoor environment.

What to Consider When Choosing Energy Saving Products

Compatibility with Existing HVAC Systems

Ensure energy saving products integrate seamlessly with your current HVAC system to achieve optimal performance.

Energy Efficiency Ratings

Choose products with high energy efficiency ratings like ENERGY STAR certification to ensure maximum energy savings.

Cost-Effectiveness and Return on Investment

Assess the upfront cost and overall long-term savings potential to determine the most cost-effective energy saving solution.

Installation and Maintenance of Energy Saving Products

Professional Installation vs. DIY

Some energy saving products will require professional installation to ensure proper functionality, others can be installed as DIY projects.

Regular Maintenance and Inspection

Scheduling routine maintenance and inspections helps keep energy saving products in top condition, maximizing their efficiency and longevity.

Troubleshooting Common Issues

Learning how to identify and resolve common issues that may arise with energy saving products ensures they continually perform at their best.

Achieving Energy Efficiency in HVAC Systems

To achieve energy efficiency in commercial HVAC systems, one should consider the following steps:

• Improving building envelope insulation and sealing the exterior building envelope reducing infiltration of unconditioned air can limit heat loss from the building.
• Adjust the thermostat settings according to the occupancy and weather conditions to avoid simultaneous use of heating and cooling.
• Perform regular maintenance and replace old or inefficient equipment with ENERGY STAR certified models.
• Harness renewable energy sources and reduce fossil fuel consumption with heat pumps and solar heating.
• Reducing the cooling or heating load and taking advantage of natural conditions can be achieved by using demand-controlled ventilation and economizers.
• Use variable speed drives, temperature resets, and zone controls to optimize heating circuits.
• Use programmable controls and sensors to implement energy-saving strategies. Optimal start/stop, night setback and setup, night purge, morning warm-up, etc. are a few examples of the tools available.
• Circulate air and improve comfort levels with fans.
• Installing humidifiers in your HVAC equipment will increase comfort levels and lower heating energy.

HeatSavr is an innovative liquid pool cover solution that helps conserve energy, reduce water evaporation, and maintain optimal pool temperatures in indoor natatoriums. This cutting-edge product creates an invisible, energy-efficient barrier that retains heat and minimizes the need for costly pool heating systems.

How HeatSavr Works

• Surface Tension – HeatSavr’s unique formula leverages surface tension to create an ultra-thin, invisible layer on the pool’s surface.
• Heat Retention – This barrier helps trap heat within the pool, reducing the need for constant heating to maintain ideal temperatures.
• Evaporation Reduction – By minimizing water evaporation, HeatSavr significantly cuts down on water loss and the associated energy costs of refilling the pool.

Installation and Maintenance of HeatSavr

• Application – HeatSavr is easily applied to the pool’s surface using a simple dosing system or manual application.
• Maintenance – The liquid cover requires periodic replenishment, typically every 2-4 weeks, to maintain its effectiveness.
• Compatibility – HeatSavr is compatible with a wide range of pool systems and can be used in both new and existing indoor natatoriums.

Benefits of Using HeatSavr in Indoor Natatoriums

• Energy Savings – Reduces the energy required to heat the pool, leading to significant cost savings on utility bills.
• Water Conservation – Minimizes water evaporation, reducing the need for frequent pool refilling and water consumption.
• Comfortable Environment – Helps maintain a consistent, comfortable water temperature for swimmers and staff.
• Sustainability – Contributes to a more environmentally friendly and energy-efficient indoor natatorium.

Conclusions and Recommendations

HeatSavr has a track record of success in indoor natatoriums, delivering tangible benefits and a rapid return on investment. The simple application and maintenance process make HeatSavr an accessible and user-friendly solution for any indoor pool facility. By adopting HeatSavr, indoor natatoriums can become more energy efficient and environmentally responsible.

Endotherm can revolutionize your heating or cooling system with its advanced formula. It enhances energy efficiency, reduces costs, and minimizes environmental impact. Add Endotherm today and start experiencing unmatched energy savings.

How Endotherm Works

One of the key aspects Lexus Engineering considers when designing or optimizing hydronic heating and cooling systems is water surface tension. Water surface tension is the tendency of water molecules to stick together and form a thin boundary layer at the interface with air or other fluids. This property could affect the flow rate, pressure drop, heat transfer, and pumping power of the system. By reducing the water surface tension, we can achieve several benefits:

• Increasing the flow rate and reducing the pressure drop in pipes and fittings can lower the pumping energy consumption and operating costs of the system.
• Enhancing the heat transfer coefficient and reducing the thermal resistance between the water and the heat exchanger surfaces can improve the efficiency and performance of the system.
• Reducing the formation of air bubbles and cavitation in pumps and valves can prevent noise, vibration, erosion, and damage to the system components.
• Improving the wetting and spreading of water on surfaces can reduce the risk of corrosion, fouling, and scaling in the system.

Different methods to reduce the water surface tension can be used, such as adding surfactants, nanoparticles, or electric fields to the water. Each method has its advantages and disadvantages and requires careful evaluation of its feasibility, compatibility, safety, and environmental impact. Lexus Engineering always weighs the benefits and costs of reducing the water surface tension when used in hydronic heating and cooling applications.

Endotherm’s unique formula enhances energy efficiency by reducing friction and improving heat transfer within your heating or cooling system. Addressing the root causes of energy loss can minimize wasted resources and maximize the output of your system. Experience the science that drives Endotherm’s overall effectiveness.

Installation Process

It’s simple. Add a calculated amount of Endotherm to your existing system in a few simple steps. Lexus Engineering with its knowledgeable sales and field technicians will provide a comprehensive guide to ensure a seamless integration, allowing you to harness the full potential of this energy-saving solution. Follow our expert tips and best practices to optimize your installation experience.

Energy Savings

Endotherm unlocks substantial energy savings. Benefit from Lexus Engineering’s reliable data and statistics that demonstrate the remarkable reduction in energy consumption achieved by integrating this additive. Endotherm has been independently proven to reduce fuel consumption by up to 15% savings.

Environmental Impact

Endotherm not only produces energy savings but also makes a positive contribution to our environment. Discover how this innovative solution minimizes greenhouse gas emissions and preserves natural resources. Compare the environmental impact of Endotherm with traditional heating or cooling methods.

Endotherm – A Quick Investment Return

Endotherm is an affordable and accessible solution for optimizing your heating or cooling system’s efficiency. Act today and join the community of satisfied customers who have experienced significant energy and cost savings. Call Lexus Engineering for pricing on your system requirements. We can keep you updated on potential discounts or deals to make your energy-saving investment even more cost-effective.

Are you and your business looking for ways to save money and enhance efficiency?

Discover the Power of Efficiency: Uncovering Savings With an Energy Audit. An energy audit can be a great way to discover potential savings that are often overlooked. The energy audits provide invaluable insights into the areas where your business is wasting resources, as well as opportunities for improvement. With an energy audit specialist by your side, you have access to unbiased findings that assess how you’re using—or misusing—energy in both the short term and the long term. Ready to reap the rewards of efficiency? Let’s uncover the financial windfall waiting with an energy audit!

Why an energy audit can help businesses save money and become more efficient and stop wasting energy

An energy audit is a comprehensive analysis of a building’s energy use that can help businesses identify areas for improvement and develop an action plan for becoming more efficient.

With the help of an energy auditor, a business can identify potential problems such as outdated lighting or inefficient heating systems, and develop a plan to address them. The energy audit also includes recommendations for making improvements that will help save money in the long run.

For example, the auditor may recommend installing a more efficient HVAC system or switching to LED lighting, both of which could lead to significant savings over time. The energy audit should also provide information about available incentives and tax credits that could make improvements even more affordable.

In addition to saving on electricity bills, implementing some of these changes can also result in increased employee productivity and improved morale due to better indoor air quality and comfortable office temperatures. Ultimately, an energy audit provides valuable insight into where businesses are wasting energy and how they can become more efficient. By following through with the recommended changes, businesses can not only save money but also can reduce their environmental impact by reducing greenhouse gas emissions.

What is an energy audit?

An energy audit is an in-depth assessment of how a building uses energy. It evaluates the efficiency of existing energy systems, equipment, and resources, and identifies opportunities to reduce energy costs. The audit can include an analysis of the building’s overall energy use, as well as individual components such as HVAC systems, lighting fixtures, and appliances. An energy audit typically involves measuring the amount of electricity and natural gas being used by the building and identifying areas where energy is being wasted.

Once completed, an energy audit will provide recommendations for improving the building’s efficiency, such as installing more efficient lighting or adding insulation to walls and ceilings. Implementing these recommendations can help reduce utility bills while also making buildings more comfortable and efficient. These audits are increasingly important as businesses seek to reduce money on their utility bills while reducing their environmental impact.

Benefits of having an energy audit specialist by your side

Having energy auditors by your side can be one of the most beneficial investments you can make for your business.

Maintaining the energy efficiency of a business can be an intimidating task, but luckily skilled professionals exist to help. Energy auditors are highly trained experts equipped with knowledge and experience that enables them to assess your company’s current usage for detecting problem areas where resources may be wasted. Their goal is twofold: not only do they advise solutions on how you could save money by making adjustments in order to maximize output while minimizing costs; but they also strive toward achieving sustainable progress within businesses across industries leading towards environmental benefits too!

Typically energy audits begin with evaluating the current state of a building’s infrastructure. This includes assessing insulation levels, sealing cracks in walls or windows, checking for air leaks and other insulation issues, analyzing heating and cooling systems, inspecting ductwork, and more.

Energy auditors have access to specialized equipment such as blower door tests which measure airtightness in buildings; infrared cameras which detect heat loss; and combustion analyzers which identify combustion problems in furnaces. After assessing a building’s current state of efficiency, the energy auditor can then recommend strategies to help improve energy usage.

These strategies could include things such as installing programmable thermostats, upgrading insulation levels, adding additional weatherstripping around windows and doors, sealing air leaks near pipes or vents, installing low-flow showerheads and toilets to reduce water waste, switching out inefficient lighting fixtures for LED models that use less electricity, cleaning or replacing HVAC filters regularly for improved air quality within your business.

Overall having experienced energy auditors on board can save time and money as they will be able to provide tailored advice based on your specific needs. They will also be knowledgeable about any relevant government incentives that may be available for making certain upgrades within the building which could further reduce costs associated with increasing its energy efficiency.

In addition, having an independent third-party evaluate a building’s infrastructure can bring peace of mind knowing that all potential sources of wasted energy have been identified so you know exactly what needs attention before taking any measures towards improving it.

The Steps to take to begin the energy audit process

The energy audit process is an important tool for identifying areas in a building that could benefit from improved energy efficiency.

An energy audit begins with a comprehensive assessment of all the sources of energy usage within a building, including lighting, heating and cooling systems, appliances, and other electrical devices. This assessment will help identify items that are using more energy than they should be and indicate where improvements can potentially be made. Once the assessment has been completed and potential problem areas have been identified, further testing may be done to confirm what is found.

Testing may include blower door tests to check for air leakage and infrared scans to detect abnormal temperatures within wall cavities. The data collected from such tests are used to develop recommendations for improving the efficiency of the space in question. These recommendations typically involve upgrades such as replacing inefficient windows and doors, installing insulation, or replacing aging HVAC systems. Ultimately, implementing any changes identified through an energy audit process can lead to substantial savings on utility bills and greater comfort in the building.

In addition to financial benefits, making use of this process also helps reduce emissions associated with excessive energy use.

All in all, taking advantage of an energy audit is an excellent way to start improving your property’s energy efficiency rating and helping protect our environment!

Natural Resources Canada for energy efficiency

Natural Resources Canada (NRCan) is a government agency that is responsible for managing Canada’s natural resources.

The agency’s mission is to ensure the responsible development and use of Canada’s natural resources, including energy, minerals, forests, and water. NRCan is also responsible for developing and implementing policies and programs that promote energy efficiency and the use of renewable energy sources.

One of the ways that NRCan promotes energy efficiency is through its energy audit program. This program provides funding for building owners and managers to conduct an energy audit and implement the recommended energy-saving improvements. The program is designed to help building owners and managers reduce energy costs, improve indoor air quality, and reduce the environmental impact of their buildings.

In addition to its energy audit program, NRCan also provides information and tools to help building owners and managers improve their efficiency. This includes publications, online resources, and training programs that provide information on energy-saving technologies and best practices. The agency also conducts research and development to support the development of new energy-efficient technologies and to improve the understanding of energy consumption in buildings.

NRCan also plays a role in promoting the use of renewable energy sources such as solar, wind, and geothermal energy. The agency provides funding for the development of renewable energy projects, conducts research to support the development of new renewable energy technologies, and provides information and tools to help building owners and managers understand the benefits of renewable energy and how to incorporate it into their buildings.

In summary, NRCan is a government agency that is responsible for managing Canada’s natural resources including energy. NRCan promotes efficiency through its energy audit program and provides information and tools to help building owners and managers improve efficiency. The agency also promotes the use of renewable energy sources such as solar, wind, and geothermal energy.

How long does an energy audit take?

The duration of an energy audit can vary depending on the size and complexity of the building being audited, as well as the type of audit being conducted.

Commercial buildings

Level 1 energy audit can take as little as a few hours to complete, while a more comprehensive Level 2 or Level 3 energy audit can take several days or even weeks to complete. The time required for a Level 2 or Level 3 energy audit will depend on the size and complexity of the building, as well as the number of systems and equipment that need to be evaluated.
More Info Here

Take advantage of the rebates available in the Province of Alberta. Discover the Power of Efficiency: Uncovering Savings With an Energy Audit

In Alberta, there are several rebates and incentives available to building owners and managers to help offset the cost of an energy audit and energy-saving improvements:

• Alberta Energy Efficiency (EE) Program (AEEP): AEEP provides funding for energy audits and energy-saving improvements for eligible industrial and commercial buildings. It also provides funding for the development of renewable energy projects such as solar and wind.
• The Energy Efficiency Alberta’s Residential and Small Business Program: This program provides rebates for energy-efficient equipment and upgrades, including insulation, windows, heating, ventilation, air conditioning systems, and more.
• Energy Savings for Businesses Program (ESB): This program provides rebates for energy-efficient equipment and upgrades for eligible businesses, such as LED lighting and more.

It’s worth noting that these programs may change over time, and it’s important to check the current availability, terms, and conditions of the incentives and rebates. Building owners and managers should also check with their local utility companies and municipalities to see if any other rebates or incentives are available.

How much is an energy audit in Edmonton, Alberta?

The cost of an audit in Alberta can vary depending on the size and complexity of the building being audited and the type of audit being conducted.

A basic audit, also known as a Level 1 audit, is generally the least expensive option and typically costs between $500 and $2,000. A Level 1 audit typically includes a visual inspection of the building and a review of utility bills to identify potential energy-saving opportunities.

A more comprehensive audit, also known as a Level 2 audit, can be between $2,000 and $10,000. Level 2 audits typically include a more detailed analysis of the building’s energy performance, including the use of specialized equipment such as thermal imaging cameras and blower doors, and provide more detailed recommendations for energy-saving improvements.

A Level 3 audit, also known as a detailed or advanced audit, is the most comprehensive type of audit and can cost $10,000 or more. Level 3 audits typically include a detailed analysis of the building’s energy performance and provide a comprehensive list of recommendations for energy-saving improvements. It is usually used for larger and more complex buildings and can include detailed monitoring of the building’s energy consumption.

It is worth mentioning that some government incentives and programs may be available in Alberta to support building owners and managers in the funding of an energy audit and implementing energy-saving improvements. For example, the Alberta (EE) Program (AEEP) provides funding for energy audits and energy-saving improvements for eligible industrial and commercial buildings.

What does ASHRAE mean?

ASHRAE, or the American Society of Heating, Refrigeration, and Air-Conditioning Engineers, is a professional organization that focuses on the advancement of heating, ventilation, air conditioning, and refrigeration (HVAC&R) systems and technologies. Founded in 1894, the organization is dedicated to promoting sustainable technology and energy efficiency in the built environment.

ASHRAE is known for developing standards, guidelines, and codes that are widely used in the HVAC&R industry, including the widely used Standard 90.1 for energy-efficient building design. Additionally, the organization provides educational and networking opportunities for professionals in the field and conducts research on topics such as indoor air quality and energy efficiency. Overall, ASHRAE plays a significant role in shaping the HVAC&R industry and promoting sustainable and energy-efficient building practices.

What does ASHRAE 62.1 mean?

ASHRAE 62.1 is a standard developed by the American Society of Heating, Refrigeration, and Air-Conditioning Engineers (ASHRAE) that sets ventilation requirements for commercial and institutional buildings.

The standard is intended to provide a minimum level of indoor air quality that will protect public health and comfort. The standard provides ventilation rates and other requirements for different types of spaces and building occupancies, such as offices, classrooms, and laboratories.

The standard also includes provisions for controlling the introduction of outdoor air, as well as guidelines for maintaining and operating the ventilation system. The standard applies to new and existing buildings and is often adopted by local authorities as a part of their building codes. Overall, ASHRAE 62.1 is an important standard that helps ensure that the indoor air quality of commercial and institutional buildings is safe and healthy for the occupants.

Reap the rewards of efficiency with an energy audit

Most companies believe that the energy audit is a great way to boost their business’s efficiency and save money in energy costs in the long run.

An energy audit will assess all aspects of your business’s energy use and identify areas where improvements can be made. With an energy audit, you’ll be able to pinpoint where you can save through efficiency initiatives such as using better insulation, upgrading outdated appliances, or installing advanced lighting systems. Additionally, an energy auditor will provide advice on how to reduce any unnecessary or wasteful uses of electricity. Making small changes can add up over time and help you lower your energy bills significantly.

Not only does an energy audit help you reduce energy costs, but it can also improve the overall comfort level inside your business.

For example, if you have poor insulation in your building then it won’t keep heat in during winter months and could cause uncomfortable drafts throughout the building. An auditor will be able to identify any problems with insulation and suggest ways to fix them.

Finally, investing in an energy audit can give you peace of mind knowing that all of your appliances are running efficiently and safely. A qualified auditor will make sure that everything is up to code so that there are no safety hazards due to electrical malfunctions or outdated technology. An investment in an energy audit now can save money down the line by avoiding costly repairs.

Overall, taking the time for an energy audit is a smart choice for people wanting to reap the rewards of efficiency while saving in the long run. With improved comfort levels and fewer safety hazards, an energy audit offers many benefits that make it worth considering for anyone wanting to upgrade their business’s efficiency.

All in all, a well-executed energy audit can help businesses benefit from long-term savings, efficiency, and a sense of sustainability. Not only would conducting an energy audit create reduced operating costs, but it would also increase company reliability and the lifespan of the equipment. With the guidance and expertise of an energy auditor, business owners can easily embark on their journey toward improved efficiency.

Now that you know the crucial benefits associated with an energy audit, it is time to get started on the process. Don’t be intimidated by how daunting or expensive the process may seem – ultimately, the rewards of efficiency will outweigh any challenges you face leading up to completion. Reap the rewards of efficiency with an energy audit and bring down those energy costs and grow your business.

Contact us today for your Energy Audit

Overview

Controlling exposures to occupational hazards is the fundamental method of protecting workers. Traditionally, a hierarchy of controls has been used as a means of determining how to implement feasible and effective control solutions.

One representation of this hierarchy is as follows:

The idea behind this hierarchy is that the control methods at the top of the graphic are potentially more effective and protective than those at the bottom. Following this hierarchy normally leads to the implementation of inherently safer systems, where the risk of illness or injury has been substantially reduced.

Elimination and Substitution

Elimination and substitution, while most effective at reducing hazards, also tend to be the most difficult to implement in an existing process. If the process is still at the design or development stage, elimination and substitution of hazards may be inexpensive and simple to implement. For an existing process, major changes in equipment and procedures may be required to eliminate or substitute for a hazard.

Engineering Controls

Engineering controls are favored over administrative and personal protective equipment (PPE) for controlling existing worker exposures in the workplace because they are designed to remove the hazard at the source before it comes in contact with the worker. Well-designed engineering controls can be highly effective in protecting workers and will typically be independent of worker interactions to provide this high level of protection. The initial cost of engineering controls can be higher than the cost of administrative controls or PPE, but over the longer term, operating costs are frequently lower, and in some instances, can provide a cost savings in other areas of the process.

Administrative Controls and PPE

Administrative controls and PPE are frequently used with existing processes where hazards are not particularly well controlled. Administrative controls and PPE programs may be relatively inexpensive to establish but, over the long term, can be very costly to sustain. These methods for protecting workers have also proven to be less effective than other measures, requiring significant effort by the affected workers.

Source: National Institute of Occupational Safety and Health (NIOSH)

Pre-Procedural Rinse

Studies indicate the use of pre-procedural rinse prior to every procedure reduces the incidence of colony forming units in splatter and bio aerosols.

An effective method of mitigating bio-aerosols is to use preprocedural rinse prior to dental procedures in conjunction with intra oral and extra oral evacuators during the procedure.

Proponents of intra-oral HVE and saliva ejectors argue:

“We have reduced the risk of infection haven’t we or the probability of it. It is impossible to completely eliminate the risk of infection.”

And it is true – no method can effectively remove 100% of particulates or claim to do so at least.

It was found that bacterial contamination from colony forming units in bioaerosols was reduced by 87% with use of intra-oral high-volume evacuators in conjunction with preprocedural rinse during procedures when the HVE was placed within the oral cavity.

(https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4860938/). However, the use of only one of the two methods exclusively only reduced the CFUs (colony-forming units) by only 60%.

Colony forming units in Bio-Aerosols and Splatter in Dental Settings

Relying on Intra Oral Suction Devices Exclusively – THE STUDIES

Intra oral devices do work but the effect of such devices is limited.

1. First the strength of suction field or the strength of the suction velocity created by the suction terminus (diameter 8mm to 12m) of the intra oral device drops at an inverse ratio with the square of the distance from the terminus. For e.g. At 2 inches from the tip of an 8mm terminus the velocity is only 15% of the suction terminus velocity.

2. Secondly, the thin suction tube would imply a higher-pressure gradient or more energy requirements to effectively create the air flow needed to evacuate the bioaerosols from the space. This would imply a bigger pump to effectively capture all particulates and aerosols generated.

3. Thirdly, high velocity projectiles emanating from the patients mouth due to coughing or scaling/drilling procedures would not be mitigated by the intra oral device.

The Computational Fluid Dynamics (CFD) image below shows the inherent flaw in the usage of plume evacuators like saliva ejectors or intra oral HVEs in the dental setting. The high velocity suction field created is close to the tip of the suction point of plume evacuation devices like saliva ejectors and has virtually no effect in surrounding spaces.

(Computational fluid dynamic modelling and simulation evaluation of the plume evacuation device efficiencies F. Farshad1, H. Rieke1, L. C. LaHaye2 & S. C. Nulu1 1 University of Louisiana at Lafayette, USA 2 Vision Pro LLC, USA)

Any particulates that are coughed or induced into the space will not be mitigated by the intraoral HVE. Procedures like ultrasonic scaling which generate high velocity aerosols would not be mitigated using intra oral suction devices.

The high static losses through the intraoral suction device would imply that there is minimal evacuation of bioaerosols as the flow rate through the suction device would be minimized by the high losses. To offset the losses, a bigger sized pump would be needed to offset the higher energy losses to achieve the same level of effectiveness.

Now let us consider an evaluation of the efficiencies of intra oral high-volume evacuation devices in colony forming units at 12 inches to 20 inches from the patient’s oral cavity during scaling procedures.

(https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4206761/) The paper titled Efficacy of High-Volume Evacuator in Aerosol Reduction: Truth of Myth? A Clinical and Microbiological Study – shows absolutely no reduction in CFUs with intra oral high-volume evacuators (placed within the mouth) on plates placed at a distance 12″ or 20″ away from the patients’ oral cavity during ultrasonic scaling procedures.

In this paper, it has been shown experimentally that intra oral suction devices provide little to no benefit in reduction of colony forming units (CFU) and mitigation of bioaerosols during scaling procedures as a result of the high velocity aerosols and splatter generated during the process.

What is a BETTER solution? Do you have studies to prove your point?

A BETTER Solution- Extra Oral Suction ALONG WITH Intra-Oral devices AND Pre-procedural rinse.

Transparent Source Capture or extra oral HF-HVE hoods (hands-free high-volume evacuator) that totally encapsulate the face of patient with provisions for dental providers to conduct procedures on the patient ensure much more safety. This should never be used alone but only in conjunction with intra oral evacuators and preprocedural rinse

A better solution is to use a modified HVE like an extra oral hood with a suction fan and filtration unit in conjunction with intra oral devices and preprocedural rinse. They are much more effective in mitigating aerosols and protecting the clinician interfacing with the patient.

Existing hands-free high-volume evacuators can also be retrofitted with source capture hoods positioned as a face mask above the patient.

https://sbdmj.com/052/052-05.pdf – In the study titled “Effectiveness Evaluation of Different Suction Systems”

A comparative analysis was conducted to verify the relative efficiencies of direct capture using intra-oral, extra oral devices and intra oral devices in conjunction with extra oral suction devices.

The experimental study above has found that extra oral suction devices can provide 18 times the protection relative to using intra oral suction devices.

The level of protection is even more comprehensive when extra oral devices are used in conjunction with intra oral suction devices as shown in the images below from a study titled

Intra-oral vs. Extra-oral Suction Devices A review of the effectiveness of equipment on capturing aerosols, And, how much Extra-Oral Suction can prevent dental aerosols? Fluid dynamic analysis of aerosols with EOS by the American Association of Oral and Maxillofacial Surgeons (AAOMS)

(https://www.aaoms.org/docs/COVID-19/Motegi_et_al_English.pdf, https://www.aaoms.org/docs/COVID-19/Intraoral_vs_Extraoral_Suction_Devices.pdf)

Intra Oral Suction Alone: Aerosol Particles went upward around the mouth and then fell down

Intra Oral Suction with Extra Oral Suction: Aerosol Particles went upward toward hood.

How can Lexus Engineering help you?

We at Lexus Engineering are specialists in the field of indoor air quality.

Our research and expertise will help guide you to make targeted choices for your clinical needs. We can assist you in picking the right solution to make your clinic a safer one.

Custom packages can be designed to best cater to your clinic’s requirements. Call us today for a free HVAC assessment at 780-435-4544 and find out how we can help you.

References:
1. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4206761/ – Efficacy of High-volume Evacuator in Aerosol Reduction: Truth or Myth? A Clinical and Microbiological Study
2. https://pubmed.ncbi.nlm.nih.gov/12271865/ – https://safedentistryinc.com/wp-content/uploads/2020/06/J-2002-A-Laboratory-Comparison-of-Evacuation-Devices-on-Aerosol-Reduction.pdf – A laboratory comparison of evacuation devices on aerosol reduction
3. https://pubmed.ncbi.nlm.nih.gov/15127864/ – Aerosols and splatter in dentistry: a brief review of the literature and infection control implications
4. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4860938/ -Role of preprocedural rinse and high-volume evacuator in reducing bacterial contamination in bioaerosols
5. https://www.nu-bird.com/dentistry-technology-and-hv-evolution – Dentistry, Technology and HV-Evolution

But what makes the dentistry profession so dangerous?

What are the Risks?

Dentists and dental hygienists are routinely exposed to many forms of airborne contaminants.

They come from dental procedures including root canals, implants, extractions, and scaling.

These procedures are called aerosol-generating procedures (AGPs).

They form saliva-laden splatter rich in blood, plaque, debris, secretions from the gums and the micro bio-flora from the oral biofilm which is home to over 1000 different species of micro-organisms. Some of the most worrisome sources of airborne contamination in dentistry are bioaerosols, mixtures of air from a handpiece, water from the dental-unit waterline, and debris from the patient’s mouth.

Many of the micro-organisms can be infectious, and they can also get aerosolized into particulate sizes less than 0.1 to 4 um. These microscopic droplets can hover in the air for up to 6 hours and have a substantial range.

The larger saliva-laden splatter naturally deposits on all surrounding surfaces like the floor, chairs, surfaces, masks, equipment, face, mouth, eyes and skin, hands and clothing of the provider and patient.

However, the bioaerosols can get suspended in the air, and find their way around the dentistry through the HVAC system and through air movement between spaces.

A “Toxic Cloud” of Bio-Aerosols

As one American dentist described it, “a toxic cloud spans from the floor to a height of six feet. The concentration of bacteria in this cloud is usually as high as 100,000 bacterium/cubic feet of air. Among the pathogens commonly found in this “cloud”:

• Staphylococcus aureus
• Acinetobacter wolffii
• Legionella
• Aspergillus
• Mycobacterium tuberculosis
• Streptococcus
• Varicella-zoster

Bio-aerosol concentrations in the dental setting skyrocket during and immediately after dental treatments.

Can they transmit between spaces and people? – Most definitely!

Aerosolized pathogens have extremely significant travel ranges from 160 to 200 ft. These airborne pathogens / commensals can stay in the air for long periods of time and travel through the building’s HVAC system.

Closing the Loop in Infection Control

In healthcare, air quality is one of the most easily forgotten components that have a significant impact on the health of indoor occupants.

The constant traffic of patients, staff and visitors, the use of high-speed mechanical tools (Aerosol generating procedures) are all generators and contributors to aggregate microbial contamination.

Another aspect often overlooked, is the use of chemicals in cleaning and sterilization of dental clinics. These chemicals can release volatile organic compounds into the air or VOCs which can affect the health of the space occupants.

Dental protocols are usually comprehensive to address contamination from hands/skin and surfaces but are not enough to mitigate the microbial burden from air contamination.

Air disinfection thus becomes one of the most critical and overlooked factors in the design of dental clinics which could have an impact on the safety and wellbeing of patients, staff, and visitors alike.  

The others are surfaces and hands/skin. Reiterating the three important factors that need to be looked at for effective infection control, they are

• Hands/Skin (Direct Contact Transmission)
• Surfaces (Indirect Contact Transmission)
• Air (Airborne Transmission)
• Aerosol Transmission (during and after Aerosol Generating Procedures)

So, how can we mitigate these risks?

The risk for infection can never be completely eradicated but the probability of infection and transmission can be reduced substantially. The 4 steps of risk mitigation include an acceptance of the risk, avoiding the risk, reducing the risk, and transferring the risk
By means of:

• Architectural Design of Spaces to minimize transmissibility of aerosols and negative pressurization of spaces is the first step in the process. – Acceptance of Risk. The layout should always be optimized to mitigate risks present. This affirms an understanding and acceptance of the risk and sets the stages to a successful dental setting.
• Engineering Controls including ventilation, pressurization, filtration, source capture hoods, filtration units with HEPA filtration units and Germicidal UVC and activated carbon media for mercury mitigation, centralized systems capable of air filtration. Engineering controls are the second step and should be designed to completely avoid the indoor risks to occupants and environmental risks present to the public.
• Personal Protective Equipment including high volume evacuators, saliva ejectors, face shields, extra oral suction devices with hoods encapsulating patients, masks (N95), surgical masks (not very effective). – This should be considered only as a last resort if adequately designed systems are not present to protect space occupants. This reduces risk but is not a fail-safe method of mitigation.
• Administrative & Procedural Controls – usage of spaces based on their design, fallow times between patients in a space based on ventilation rates, scheduling strategies for Aerosol generating procedures (AGPs) in rooms and minimization of AGP procedures, surface disinfection protocols etcetera.-  Risks are not mitigated in this case but only transferred from one occupant to another. It is like an insurance policy in the sense that one party is always exposed to the risk.  Risk reduction strategies need to be used in conjunction with such controls to protect indoor occupants.

“Every patient should be treated as potentially infectious.”

Dental procedures on patients need to be conducted under protected environments to ensure the safety healthy of your staff, including hygienists, and dentists.

In today’s pandemic world, no precaution can be deemed excessive.

High volume evacuators, preprocedural rinse, face shields are recommended by the Alberta Dental Association and College, all of which are steps in the right direction towards mitigating these risks.

We should be cognizant of the fact that

“There is no threshold for concentration of viruses, pathogens and particulates in causing infectious disease”

An evacuator that reduces the concentration of contaminants from 5 mg/m3 to 0.5 mg/m3 is still of no use as the number of viruses in the lowered concentration could be still be equally infectious as the unmitigated volume.

And as they say,

NEVER GUESS ABOUT AIR FLOW. AIR HAS A MIND OF ITS OWN.

Lexus Engineering will help you visualize your airflow and help you optimize it through advanced CFD software.

WHAT IS CFD? How can it help us?

A CFD (Computational Fluid Dynamics) study can be used to understand airflow dynamics in any space and airflow patterns can be optimized based on this study by the correct placement of diffusers and grilles.

The picture below shows airflow patterns and the path of airborne contaminants based on a CFD Analysis.

• Large particles/droplets fall near the source
• Small particles/aerosols remain airborne
• Aerosols follow the path of flow of air
• Density, shape, and size of particles will affect its dynamics
• Droplets can evaporate and become aerosol and airborne
• External forces like a fan (HEPA Unit) can affect the trajectory if the aerosols are on the positive pressure side of the blower

How can Lexus Engineering help you?

We at Lexus Engineering are specialists in the field of indoor air quality.

Our research and expertise will help guide you to make targeted choices for your clinical needs. We can assist you in picking the right solution to make your clinic a safer one.

Custom packages can be designed to best cater to your clinic’s requirements. Call us today for a free HVAC assessment at 780-435-4544 and find out how we can help you.

References:

1.  Efficacy of High-volume Evacuator in Aerosol Reduction: Truth or Myth? A Clinical and Microbiological Study
2. A laboratory comparison of evacuation devices on aerosol reduction
3. Aerosols and splatter in dentistry: a brief review of the literature and infection control implications
4. Role of preprocedural rinse and high-volume evacuator in reducing bacterial contamination in bioaerosols
5.  Dentistry, Technology and HV-Evolution

It is an invisible, TOXIC, odorless, tasteless, radioactive noble gas. It occurs naturally when uranium (radioactive element) in the soil and rocks break down. It is formed by the disintegration of radium (radioactive element), a decay product of uranium. When radon is released from the ground into the outdoor air, it is diluted and is not a concern. However, in enclosed spaces like homes, it can accumulate to high levels. High radon levels can be a risk to the health of you and your family.

Radon produces several solid radioactive products called radon daughters or “progeny”.

Some amounts of radon gas are present naturally everywhere in the soil, water, and air. However, high radon levels occur in regions predictably where the soil or rock is rich in uranium. It can enter the indoor air where it (and its progeny) can accumulate in poorly ventilated areas.

Radon progeny are inhaled with air and deposited in the lungs. The lung absorbs alpha particles emitted by the radon progeny. The resulting radiation dose increases the risk of lung cancer.

The following figure (Figure 1) illustrates the radioactive decay chain that produces radon and radon progeny.

Figure 1. Production of radon and radon progeny from uranium

What is the danger present in inhaling Radon? Is it true I can get cancer from radon exposure?

Radon can quickly disintegrate into other radioactive elements in our lungs after inhalation. It is the second most prevalent cause of lung cancer in the Americas (including Canada and the United States) after smoking.

An estimated 1 in 3 smokers will be susceptible to lung cancer due to radon inhalation and 1 in 20 non-smokers are susceptible to lung cancer due to radon inhalation. This is an alarming statistic and needs to be addressed at the source.

Figure 2. Annual Deaths in Canada from Radon compared to others

Figure 3. Annual Deaths in Canada from Radon compared to others

What are units of measurement of Radon Gas? What is the current guideline for Radon in indoor air?

Since radon is a product of radioactive decay, the units of measurement are Bq/m3 (Becquerel/m3, Becquerel named after Henri Becquerel is a unit denoting Radioactive decays per second) or pCi/L which is (Pico-Curie per liter). The Radon mitigation standards developed by the EPA require that the concentration in indoor spaces do not exceed 4 pCi/L. 1 pCi/L equals 37 Bq/m3. The Canadian standard for Radon levels is 200 Bq/m3. Most homes can be mitigated below 75 Bq/m3

Figure 4. Canada Radon Levels

Acceptable levels of radon in “dwellings” which include homes or public buildings (schools, hospitals, long-term care facilities and correctional facilities) are 200 Becquerels per cubic meter (200 Bq/m3) based on the Government of Canada Radon Guidelines

How does Radon enter my building or house?

Radium in the soil directly under a building is normally the major source of indoor radon. Other sources of radium are in groundwater and building materials.

The presence of uranium in soil and rock is an important indicator of places where radium and radon can be present. Because radon is a gas, a fraction of the radon produced in the soil can find its way into a building. The rest is trapped in the soil. In the air, radon decays to radon progeny that are solids, and are present in the building air as fine particles.

The concentration of radon and radon progeny in the indoor air depends on:

• the amount of radium in the soil and
• the ease with which the radon it produces can move through soil and building walls where it can then mix with the room air.
• Soil pressure with respect to ambient air pressure

Changes in atmospheric pressure can also affect its emission from the ground and its accumulation in the building air.

The concrete floor and walls in the basement slow down the movement of radon from the soil into the building. However, cracks in the floor, wall slab joints, and the drainage system allow radon to enter a building.

Indoor radon concentrations are almost always higher than outdoor concentrations. Once inside a building, the radon cannot easily escape. The sealing of buildings to conserve energy reduces the intake of outside air and worsens the situation. Radon levels are generally highest in cellars and basements because these areas are nearest to the source and are usually poorly ventilated.

Figure 5. How can radon get into my home?

How do I find out if there is radon in my basement?

Contact a radon mitigation professional today to determine if radon should be on top of your mind. Certified Radon testing professionals can help you determine the radon levels in your basement, home, and building. The Canadian National Radon Proficiency Program (C-NRPP) provides courses and training which helps certified professionals to test and provide a design for mitigation of high Radon levels. If Radon levels are higher than 200 – 600 Bq/m3, immediate steps must be taken  to mitigate the radon levels through an ASD (Active Slab depressurization) system which involves the installation of underground piping, a suction pit and an active vent fan as its major components. This will redirect the radon through the fan safely into the atmosphere, preventing it from entering your homes

How to mitigate radon entry into my space?

In Alberta, Radon was identified as a risk to building occupants as late as 2014 when the Alberta Building Code was updated to include the measures needed to identify and mitigate the sources through which radon can infiltrate into your building space. There are three methods of mitigating the effect of radon infiltration into the space and a combination of these three methods can be applied to effectively negate the radon that infiltrates into our living spaces.

The methods are:

• Building Pressurization
• Sub Slab Depressurization through Active and Passive Methods
• Sealing

Where do we go from here?

The best way to help is to understand the severity of the problem we are facing and conduct valid and intelligent research with the correct framework of knowledge to mitigate the problem at hand. With the experience, data, and body of knowledge that we possess, Lexus Engineering can advise you on the mitigation measures necessary to make your building and home a safe place to live.

References:
1. Alberta Building Code 2014

2. U.S. Environmental Protection Agency, U.S. Department of Health and Human Services, and U.S. Public Health Service. Radon Prevention in the Design and Construction of Schools and Other Large Buildings, June 1994
3. U.S. Environmental Protection Agency, U.S. Department of Health and Human Services, and U.S. Public Health Service. Radon Mitigation Standards, June 1994
4. U.S. Environmental Protection Agency, U.S. Department of Health and Human Services, and U.S. Public Health Service. Sub Slab Depressurization for a Low Permeability Fill, Design and Installation of a Home Radon Reduction System, July 1991

5. Health Canada Randon Gas it’s in your home

6. Canadian Centre for Occupational Health and Safety

Environmental Protection Agency (EPA) indicate that human beings spend approximately 87% of their living time indoors and another 6% in vehicles. This implies that we spend less than 7% of our life outdoors which is less than half a day or 12 hours per week. 

Indoors could imply residential, commercial, or Industrial spaces. In the US alone, commercial, and residential buildings accounted for 40% of the total national energy consumed. Throughout history, the concept of buildings has changed depending on the need to address social needs. With the advent of the technology of steel framing and other structural innovations, the idea of real estate exploded into the third dimension allowing extraordinary growth while maintaining a limited earthly footprint. However, the added complexity posed new challenges in the engineering systems required to maintain such a space at an adequate level of comfort for its occupants. 

Indoor Air Quality is one of the major factors that are most important in indicating the comfort level, general healthiness, and well-being of the occupants of the building. Indoor Air Quality includes the temperature of the air, levels of moisture in the air, and its composition which is an indicator of the level of pollutants, contaminants, and gases, all of which, play a significant impact on the well-being of the occupants of the building.

“Indoor Air Quality” as the name suggests refers to the quality of the air in a space. “Atmospheric Air” as we know it constitutes of the following gases in its elemental form: Nitrogen at 78%, Oxygen at 21%, Argon at 0.93%, Carbon Dioxide at 0.04% and the remainder being trace amounts of neon, helium, methane, krypton, hydrogen and water vapour which all exist in equilibrium with each other. Why is this important? These relative percentages of constituents are essential to the sustenance of life on this planet. A slight change in these factors can lead to a significant disruption of life itself on this planet.

All life on this planet is sustained through the mechanism of breath. Breathing is a natural process by which lungs absorbs the required amount of oxygen from the air in the atmosphere and exhales by products of ingested air back into the atmosphere. The typical lung respiratory volume for an average adult human male is 6 liters of air. This can be further subdivided into “tidal volume” which is the amount of air inhaled or exhaled during one respiratory cycle which is in the order of 500 – 750 ml, “inspiratory reserve volume” which is in the order of 3 liters, “expiratory reserve volume” which is typically 1.5 liters, and residual volume which is typically about 1 liter. The fresh air introduced into a HVAC system must account for the lung aspiration rate to offset the generation of CO2 in the space. This depends on the occupancy rating of the space. Demand Control Ventilation is a methodology employed in HVAC systems where in economizers are used to control the intake of fresh air based on the number of occupants in the space and CO2 generated because of this.

The pressure of air at sea level or 0’ ASL (above sea level) is 14.696 (psi) pounds per square inches. As the elevation changes or increases, the pressure of air reduces. At 10 000 ft ASL (3 KM), the air pressure is as low as 10 psi resulting in less oxygen to breathe. Ever felt a pain in your inner ear drum when you take off or land in an airplane. The effect is called “Barotrauma”. It is caused by the sudden change in air pressure resulting in a vacuum in the middle ear which can pull the ear drum inward. In severe cases, the middle ear can fill with fluid as the body tries to equalize pressure on both sides. At relatively high altitudes, air pressures become a quality of air that has significant impact on the comfort level of the occupants.  HVAC systems for airplane cabins typically must account for this factor in determining the amounts of recirculated air. HEPA Filters are used to decontaminate the air typically to ensure the recirculated air is free of pathogens and pollutants. Fresh Air is usually taken from the fuel system.

The temperature of the air is a quality of air that we are all familiar with. When it gets too warm, we go over to the thermostat and reduce the room temperature levels and when it gets cold, we try the opposite. Temperature is an intensive property of the air that affects its quality and the well being of the occupants.

Have you ever checked your “Humid-Stat”? This is the device that controls and regulates the relative humidity of your space. It is usually set between 40 to 50 % to ensure the well being of the building occupants. If you have felt a tinge of static electricity coursing through your fingers every time you touch your doorknob, it is an indicator that the relative humidity in your space is lower than 30%. Moisture being a good conductor of electricity helps the dissipation of electric charge freely through the air. Lower humidity levels that 30% can result in electric discharges between dissimilarly charged bodies due to a buildup of pockets of electrostatic discharge. Humidity levels more than 55% to 60% can facilitate and speed the growth of mold and mildew in buildings.

Older buildings typically have toxic asbestos fibers in its construction include ceiling tiles, walls, insulation, ducts, pipes, wall boards, wall seals and duct tapes. In the era of do it yourself home renovations, people might be unknowingly breathing contaminated air containing asbestos fibers It is essential to mitigate his hazard in the initial stages as it asbestos is a carcinogen causing unprecedented changes to the body.

Indoor Concentrations of Pollutants have increased in recent times due to increased use of synthetic materials in buildings, lack of adequate air exchanges, lack of required outdoor air rates, ineffective filtration mechanisms, specialized building usage which negates a “modular, one size fits all” approach to HVAC systems and calls for more individualized attention to HVAC systems required for the special use. The pollutants could include but are not limited to the following listed below

• Environmental Tobacco Smoke, Particulate Matter, Carbon Monoxide, NOX
• Dust and Fur from animals
• Naturally occurring Radon, Mold
• Pesticides, Lead and Asbestos
• Ozone from Air purifiers
• VOC (Volatile Organic Compounds) from cleaning products, paints, thinners, insecticides and other products and materials
• Airborne Pathogens, Viruses, Bacteria

The sources of these pollutants can be indoor or outdoor which can enter through open doors, open windows, ventilation systems and infiltration cracks in structures. Radon is an example of a pollutant that forms within the ground as uranium within rock and soil decays and can enter the structure through cracks and gaps in the foundation of the building. The water supply to a building can be a source of contaminants and chemicals into the building. Dust and Soil can enter the building through people entering the building through clothing and shoes.

Indoor Air Quality can be influenced by multiple factors including air exchanges achieved, outdoor weather conditions and occupant behavior. Air exchange rate and outdoor air rate can be the most important factor in controlling level of outdoor air pollutants and concentrations thereof. Without adequate levels of air exchanges through recirculated, fresh and infiltration air, indoor contaminants can grow at an unprecedented rate unless the source of the contaminant is dealt with.

The consequences of poor indoor air quality can be deleterious and detrimental. Lack of adequate fresh air can result in many undesirable health effects including headaches, dizziness, and fatigue. Those at risk, are those who have prior conditions related to migraine, cluster headaches, sinus sensitivities and are extremely susceptible to indoor air conditions. Indoor air pollutants in sufficient concentrations can cause irritation of eyes, nose and throat, respiratory disorders, including lung disorders, bronchial asthma, bronchitis, cancer amongst numerous others, Environmental tobacco smoke, radon, carbon monoxide, carbon dioxide, NOX, dust, mites, mold, pet fur, pet dander, particulates, particulates and allergens through insect migrants, particulate matter can be triggers in sufficient concentrations for most people include those most sensitive to it like asthma patients.

“Sick Building Syndrome:” is a name given to a condition that occurs in the occupants of a space if the environmental conditions are unsuitable for these occupants. Obviously, the building HVAC system cannot cater to everyone specific needs, however time and research have produced a body and range of data that details the ideal environmental conditions for a large subset of the population. Indoor Air quality is an ever-growing field of study that accounts for these factors and helps make improvements to the quality of our life.