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The Blower Door Test

One of the advantages of working at MWA is our team’s ability to collaborate internally – across four distinct service lines. The blower door test provides an ideal opportunity for our Commissioning engineers and Test & Balance technicians to work together, each bringing their unique skillsets and experiences to a project. Alexis, from our Commissioning team, and Dave, from our Test & Balance crew, recently traveled to Louisville, Kentucky to conduct a blower door test for a medical research facility. The client had asked us to assess the enclosure leakage rate for one of its laboratory cold rooms.

MWA uses a calibrated blower door testing system to determine the airtightness (or leakage rate) of an entire building or specified zone within a building. It’s important that both the blower door test fan and pressure gauge are calibrated. Uncalibrated blower doors can only detect leaks; they cannot measure how much air is leaking or how effective air sealing methods are.

The blower door test works by blowing air into or out of a building or enclosed space, creating a slight pressure difference between inside and outside. This pressure difference forces air through any holes or gaps in the enclosure. The tighter the building or space (i.e. the less holes or gaps in the enclosure), the less air required for the blower door fan to create a change in pressure.

A blower door test could be used as a diagnostic tool for several reasons, including:

  • To reduce energy consumption
  • To avoid moisture problems
  • To avoid drafts from outside air leaking in
  • To determine how much ventilation is needed to provide acceptable indoor air quality
  • To access the rate of air leakage for critical spaces like hospital rooms (ensuring pollutants are not coming in to clean spaces) or laboratory cold rooms (helping maintain temperature-controlled spaces)

MWA’s typical procedure for evaluating enclosure leakage rates involves the following steps:

  • Obtain floor plan drawings in order to calculate the Total Surface Area of the space to be tested. This is necessary to determine how many fans will be needed.
  • Once onsite, carefully assess the space.
  • Disable any air systems (like energy recovery units, exhaust fans, dampers, etc.).
  • Prepare the space by blocking all openings affecting the test. This includes sealing all penetrations, doors, floor drains, toilets, etc. using an adhesive plastic.
  • Notify facility personnel to ensure all doors and windows remain shut throughout the test.
  • Mount the blower door frame, flexible panel, and variable-speed fans into the doorway.
  • Pressurize and depressurize the space gradually to +/- 50-75 pascal or maximum possible pressure allowable by the available blower door. The achievable pressure will depend on the leakage condition of the room.
  • Use a handheld controller linked to analytical software to instantly collect and evaluate the air leakage data.

Following the test for the laboratory cold room, Alexis and Dave worked together to assess the data and deliver a detailed report to the client which included an executive summary, air leakage data from multiple different pressure readings, and general site observations. The test demonstrated that the space did, in fact, meet the specified air tightness criteria for laboratory cold rooms. If the space had failed to meet the requirement, MWA would have returned to perform an IR thermographic scan to locate the sources of leakage. Whether you’re trying to reduce energy costs, fix moisture problems, improve indoor air quality, or meet an air leakage rate criteria, the blower door test is a powerful diagnostic tool.

Highlighting Construction Safety

Midwest Associates’ Construction Safety team is currently onsite and leading the safety effort for one of MWA’s largest projects to date – the Indiana University Health Bloomington Hospital.

For a sense of scale, the MWA Safety team manages 500 craftworkers each day. There are 35 contractors currently onsite. Our Safety team coordinates and manages another 20 safety representatives from the subcontractors. Our Site Safety Manager has reviewed over 100 crane lift plans. As of the end of March 2021, there have been 1,856,303 hours logged.

Of course, safety is about so much more than numbers. As MWA’s Site Safety Manager, Chris Ramsey, says “Doing my job right means every person who steps onto one of my jobsites can go home to their families in the same condition they came to work that day.”

Our Safety Managers develop site specific safety plans, handle contractor qualifications, conduct safety orientations, and provide audits, reporting, and incident management. To learn more about these and additional services our Construction Safety team offers, visit our Safety page or contact us today!

Service Highlight: The Blackout Test

Utility power outages – whether from winter ice storms or spring tornadoes – are something seasoned Midwesterners tend to expect and prepare for. That’s why MWA’s Commissioning team offers a Blackout Test as part of our functional testing of a building’s emergency power system. A Blackout Test verifies that in the event of a power outage all systems operate as expected on the backup or emergency generator power.

Conducting a Blackout Test requires a great deal of planning and coordination. Prior to the test, the Commissioning Agent ensures any on-site crews and local authorities that might be affected by the test have been notified. Next, the Commissioning Agent assembles a Blackout Test Team, usually consisting of multiple Commissioning Agents, an Owner’s Representative, the General Contractor, Electrical Contractors, and the Facility Manager and personnel. This is an excellent opportunity for the facilities staff to receive training on their building’s emergency power systems.

The Commissioning Agent provides the team with a Blackout Test Equipment Checklist. The team checks that each system is operating under normal (non-maintenance or test-mode) conditions. Individual team members then station themselves at specified locations throughout the building to observe the emergency response to the simulated loss of power. Once the power upstream of the emergency generator is disconnected, the team members will record the action and time it takes for each system connected to emergency power to kick in. Typically, we expect the transfer of power to happen within 10 seconds of the initial simulated power outage.

As soon as the building is operating on backup or emergency power, the Blackout Test Team verifies that emergency panels and power outlets are active; emergency lighting, including exit lights, are energized; the fire system is energized; and that HVAC and all critical equipment, communications, alarms, and controls are active according to the construction documents. Once the test is complete, the team switches all systems back to normal power and powers down the generator.

For buildings that rely on a backup generator to continue normal operating conditions during power outages, the Blackout Test is an essential tool towards ensuring all the integrated components and systems tied to emergency power will work when needed most. So next time extreme weather is in the forecast, you can grab a hot chocolate and rest assured that your building’s emergency power system will be ready.

From the Frontlines: A Local Nurse’s Perspective

In the fight against COVID-19, our country and our world has faced many unforeseen challenges. Throughout the pandemic, we have come together to create safer spaces to live, work, learn, and heal in. Our healthcare facilities, hosting patients and frontline workers, represent one of the most crucial of these spaces.

One way Midwest Associates has been able to help is by working with our clients to improve Indoor Air Quality. MWA has had the privilege of providing Testing and Balancing services for many facilities, including hospitals, across Indiana.

We recently spoke with Ms. P. Berry, a nurse in Indianapolis, about her thoughts on the importance of Indoor Air Quality and having safe spaces for patients and healthcare heroes.

“I’ve been a nurse working on a COVID floor since March,” she said. “We truly take every single precaution to prevent the spread of COVID-19 to keep our patients and staff safe. A huge factor to this is air filtering and control. All of our patients are housed in negative airflow rooms, which keeps the air inside the patients’ rooms from spreading into the outside air, such as the hallways.”

Since early in the pandemic, MWA has helped healthcare facilities ensure pressure critical spaces like isolation rooms were meeting the Center for Disease Control and Prevention’s current standards, while also converting an increasing number of existing patient rooms into much-needed temporary isolation rooms.

As Nurse Berry reminds us, however, sometimes these services do more than just make a space safer – they change lives for the better every day.

“The balancing of air is so important. It has helped keep all of our staff safe and healthy so we can do our part and help care for people. Honestly, we would be out of jobs without negative airflow rooms – meaning there would be no one to take care of those in need! It also prevents us bringing COVID home to our families. It makes me feel super safe and is part of the reason I haven’t contracted COVID yet even though I’ve been in direct contact with it for 9 months. I truly would not feel safe at my job without it,” Berry said.

Let Midwest Associates help ensure your indoor spaces are as safe as possible – contact us today to learn more about all of our Indoor Air Quality services.

Project Highlight: IU Health Frankfort Hospital

Our Midwest Associates commissioning team is hard at work wrapping up the Indiana University Health Frankfort Hospital project!

Wayne, one of MWA’s Commissioning Project Managers, has worked closely with the project delivery team to ensure the mechanical, electrical, plumbing, and fire protection systems have been properly installed, fully integrated, and are operating at optimal performance.

The new facility includes: 12 inpatient beds, emergency care, lab services, pharmacy and imaging services, surgical suites, physical and occupational therapy, cardiovascular and pulmonary services, a helipad, staff patio lounge, public and patient therapy gardens, and greenspace with walking trails around the campus.

MWA is honored to be part of this important project. As our project partner arcDESIGN said, “the new IU Health Frankfort Replacement Hospital will be more than a hospital—it will be an entire health campus that will transform healthcare services in Clinton County. From surgery and imaging to prenatal care and cardiology, the hospital will offer patients and their families the care they need in their own community.”

In addition to testing the new equipment and controls, MWA conducted a blackout test to verify that in the event of a power outage all systems operate as expected on backup generator power. This is an essential part of commissioning hospitals and other critical facilities that rely on emergency power systems to continue normal operations during a worst-case scenario. Having worked on this project for nearly a year, Wayne expressed his satisfaction with the project, reflecting “we enjoyed working with the IU Health team to provide them with a safe workspace.”

Want to learn more about Midwest Associates and the services we can offer your project? Visit the “Contact Us” tab above.

Pressure Critical Rooms Tech Talk

Stacy Carey and Steve Jerge, Midwest Associates President and General Manager respectively, presented at the Building Commissioning Association June 2020 Tech Talk.

Along with representatives from Grumman/Butkus Associates, Stacy and Steve discussed commissioning and balancing Pressure Critical Rooms (PCRs), such as operating rooms, ICU rooms, cleanrooms and laboratories.  PCRs have very specific design, construction, and performance requirements that must be adhered to, tested, and documented. This year we’ve seen a sharp increase in the need for commissioning PCRs and creating new, makeshift PCRs for treating and testing COVID-related patients.

Our Midwest Associates team shared their years of experience commissioning and balancing PCRs and the lessons they have learned along the way to help avoid common errors.

Here are a few highlights from their presentation.

A TAB technician’s process for balancing a PCR involves the following key steps:

  • Review the drawings and specifications to understand the room requirements – for example, does the room need to have positive pressure, negative pressure, or a pressure cascade (ensuring the flow of contamination is from clean to less clean); what is the required ACH (air changes per hour)​.
  • Visually inspect the room envelope integrity.
  • Pressure test the room if required by the owner.​
  • Balance the room to design​: test and adjust all supply valves, boxes, diffusers and all exhaust valves, boxes, grilles.
  • Measure the pressure differentials using a multimeter and compare this data to the room sensor or monitor readings​.
  • If balancing multiple rooms with a cascade, start with the innermost room and “work your way out.”​
  • After the pressure differential is correct, measure the room and calculate the ACH​. The ACH is a measure of the air volume added to or removed from a defined space divided by the volume of that space. In other words, this is the number of times per hour the total volume of air in a room is changed over.

 Commissioning and TAB lessons learned:

  • Before they can complete their functional testing, commissioning providers need to review the TAB report. If a commissioning provider has any questions regarding the report, don’t hesitate to call the TAB firm and ask. Commissioning providers and TAB contractors can and should work together to achieve the best results.
  • In most cases, the initial balance to the design airflows doesn’t achieve the required pressures. TAB technicians should discuss adjustments with the design engineer.
  • Keep in mind that most balancers will measure room dimensions without taking cabinetry, bulkheads, etc. out of the room.
  • Verify the TAB instruments are within calibration​.
  • Low level return grilles can get loaded with lint from bed linens. It’s a good practice to clean them before starting balance​.
  • Best practice is to inspect the AHU and exhaust equipment, including the pressure differentials, before starting balance​.

An Overview of ASHRAE’s Updated Guidelines for Academic Buildings

The reopening of schools and universities has been a prevalent topic these past few months as institutions strive to ensure they’re providing the safest possible environment for their students and staff to learn and teach in.

It is important academic leaders continue to review and verify their plans for reducing the spread of viruses like COVID-19 are up-to-date and being followed.

At a conference this summer, the ASHRAE Epidemic Task Force presented an updated guide to reopening schools and universities, reaffirming their position that “Transmission of SARS-CoV-2 through the air is sufficiently likely that airborne exposure to the virus should be controlled. Changes to building operations, including the operation of heating, ventilating, and air-conditioning [HVAC] systems, can reduce airborne exposures.”

The collection of 41 slides includes a series of checklists to be completed for specific equipment and systems throughout the academic year. Some checklists are to be done daily such as general cleaning and flushing the air by operating the mechanical systems in occupied mode for at least 2 hours before occupancy.

Most equipment and system checks should be done on a monthly basis. Some of the monthly checklists are for major pieces of equipment like air handler units, boilers, cooling towers, and chillers. There are also checklists for single zone equipment like fan coil units and mini-splits, as well as water and steam distribution systems.

The Task Force outlines a set of “Designer Guidelines” with the goal of helping “designers retrofit and plan for the improvement of indoor air quality and to slow the transmission of viruses via the HVAC systems. The underlying effort of the designer should be to increase outside air to the spaces, treat return air and or supply air to spaces via mechanical filtration and maintain indoor comfort as defined by the design temperature and relative humidity.”

The guide also provides instructional and procedural recommendations for how facility managers can increase their existing air system’s filtration efficiency during the pandemic. The target filtration level for schools is currently MERV 13 or higher. The slides walk you through how to gather the necessary data to determine whether MERV 13 filters are compatible with your system. If MERV 13 cannot be installed, they offer alternative options for increasing filtration.

Finally, the updated guide includes a list of protocols for higher education facilities to implement, including recommendations for unique spaces like student health facilities, laboratories, athletic facilities, and residence halls.

Midwest Associates is here to help you evaluate and test how your academic buildings are performing this school year. Visit our contact page above to learn more about how our services can benefit you. To learn more about ASHRAE’s reopening recommendations, visit the link here: https://www.ashrae.org/technical-resources/reopening-of-schools-and-universities

MWA Techs Featured in The NEBB Professional

MWA’s Test and Balance technicians share their stories about working in potentially high-risk buildings during the pandemic in the latest edition of The NEBB Professional, Quarter 3 – 2020. The article, titled “Midwest Associates Test & Balance Technicians Respond to COVID-19: Helping Create Safe Spaces for Treating Patients & Testing Essential Workers,” highlights the important contributions MWA’s technicians have made, some of the challenges they faced, and lessons they learned on projects across Indiana.

Since the onset of the COVID-19 crisis, some of the ways MWA has responded to clients’ requests have been by helping hospitals ensure they meet the Centers for Disease Control and Prevention’s updated standards, converting patient rooms into temporary isolation rooms, and helping companies quickly and safely provide much-needed testing sites for essential workers.

To read the article and learn more about the essential work our amazing technicians have been doing, follow the link here: https://www.nebb.org/resources/theprofessional/

The Role of Quality Assurance at the Community Justice Campus

Midwest Associates is hard at work providing Construction Quality Assurance for the Marion County Community Justice Campus, or the CJC. The CJC consists of the Consolidated Civil and Criminal Courthouse, Adult Detention Center (ADC), Sheriff’s Building, and the Assessment and Intervention Center (AIC).

Our expert team is primarily assigned to the courthouse; however, we do assist in all of the buildings on a regular basis.

Each of our team members on site is tasked with different responsibilities. Whether we are attending meetings or reviewing the fine details of work being completed in the field, Midwest Associates is dedicated to ensuring the project is completed to the highest standards.

A large part of our work on this project consists of identifying deficiencies, reviewing the issues, and ultimately verifying they have been corrected. This process guarantees cost savings for property owners, as it reduces rework by identifying and correcting issues early in the construction process.

Our Construction Quality Assurance team is doing amazing work for the CJC project, including, but certainly not limited to:

1.) Supporting the concrete installation by reviewing and documenting most of the concrete placed on site. We help the concrete superintendent identify any potential field issues. We review elevated deck pours to ensure that the post-tension tendons, rebar, formwork, and embedded items are in per the plans and specifications. We walk with the engineer and/or 3rd party testing agency and record any deficiencies they find so that we can get them corrected prior to placement. We document the elevated deck and vertical concrete work through pre-pour cards, observations logs/maps, and Procore observations.

2.) Maintaining a pre-punch system for our concrete superintendent. Every Monday, the concrete superintendent and our team walk the building to identify deficiencies in the concrete finish and/or to document the corrections that have been made. This helps the concrete division make repairs while they have easy access to the areas before the other trades occupy the space.

3.) Reviewing the vapor mitigation system (VMS) and all of its components. We then help resolve issues in the field by facilitating communication with the VMS engineer and the vapor barrier manufacturer’s representative. We document the correction of all deficiencies using observation logs and Procore observations. We provide a similar service for the waterproofing of exterior walls and elevator pits. We often have more time to devote than the superintendents to really dig into the details of each system and ensure we are installing items per the contract documents.

4.) Attending the above ceiling walkthroughs at the AIC. We help document the deficiencies that are called out by the design team and owner’s representative. The list is published and distributed to all the subcontractors. After they have completed the necessary corrections, we come back to verify and document.

5.) Reviewing the air barrier in a similar way to the waterproofing. We meet with the subcontractor and identify areas that do not meet the manufacturer’s requirements, such as: wrong product, wrong application of the product, and/or any missed areas. Again, we document the deficiencies and verify they have been corrected.

Are you a property owner or project manager looking for a dedicated team to complete tasks like these, and more, to the highest standards? Contact Midwest Associates today.

Healthy Buildings to Help our Economy

Did you know there are many economic benefits to healthy buildings?

As we respond to COVID-19 and this uncertain time for our health and future, safe buildings AND boosting our economy are more important than ever.

Harvard experts have found that by providing more opportunities to work, learn or reside in a more health conscious building, we will also be supporting the economy.

As we move back into “normal” life post-COVID, the economic benefits for property owners who are able to market their buildings as healthier indoor spaces will become increasingly apparent. John D. Macomber, Senior Lecturer of Business Administration at Harvard Business School, explains “I think that the offices with the premier health story will get the premium rent and get the tenants, and the offices with a lagging health story will lag.”

Healthy buildings will be those that can claim improved Indoor Air Quality. Midwest Associates’ expertise in balancing HVAC systems and performance testing of mechanical systems helps property owners implement the necessary changes to achieve healthier buildings. These changes include increasing the air change frequency, increasing outside air ventilation, checking air filter installation & maintenance, and ensuring balanced room pressure differentials.

In the article "What Makes An Office Building Healthy",The Harvard Business Review states, "Researchers at Lawrence Berkeley National Laboratory have estimated that improving indoor air quality in offices could add as much as $20 billion annually to the U.S. economy. This new calculus should inspire a new generation of highly justifiable investment in creating and operating a healthy building."

Contact us today for more information on how you can make your buildings safer for your tenants, employees, and more, while also doing your part to stimulate the economy.