Tag: Indoor Air Quality

COVID-19 and Building Ventilation

Posted on by Lindsey Burbee

Keeping your HVAC breathing through the Covid-19 pandemic.

 

The United States continues the fight against COVID-19, many reopened businesses are concerned about indoor air quality. As a result, new requirements are being implemented for the public’s safety.

Recently, New York allowed for the reopening of shopping malls but with a mandate from Gov. Andrew Cuomo: Update HVAC filters with at least a MERV-11 rating to capture the potentially airborne coronavirus particles. Likewise, Colorado’s Denver Public Schools unanimously approved Denver schools to get ventilation upgrades to help stem the spread of coronavirus. So what do these guidelines mean, and could other states follow these policies?

 

 

HVAC Filters

Minimum Efficiency Reporting Value (MERV) is used to measure the effectiveness of air filters on a scale of 1 to 16. The higher the MERV rating, the greater the filtration, i.e. the smaller the particles it can catch. The Centers for Disease Control and Prevention (CDC) recommends to improve central air filtration to the MERV-13 level (or the highest compatible with the filter rack) and to seal edges of the filter to limit bypass.

 

 

MERV filter rating for HVAC systems
Model of MERV filter ratings. (Source)

 

However, updating an HVAC system’s air filters may not be as simple as it sounds. For instance, a common factor that will get overlooked is that most HVAC systems that were designed for lower MERV filters (likely most of them) will need to be rebalanced for the new filters. The higher the MERV rating, the better the filtration but also the higher the static pressure (or resistance) that the fan must work against, resulting in a drop in airflow. The reduced airflow could cause comfort problems and even frozen coils. To prevent these issues, the airflow will need to be measured with the new filters installed, and then the fan speed will need to be increased to achieve the designed airflow.

Yet this is still not a “one size fits all” solution for all. Many HVAC units cannot handle the higher-rated filters. Using a filter with a higher MERV rating may cause the motor to burn out. This is why it is important you have a trained technician review your unit before making any changes.

 

 

Other Building Ventilation Recommendations

In addition to replacing filters, ASHRAE recommends the following actions, with the ultimate goal being consistent and frequent air changes:

 

  • Increase outdoor air ventilation (use caution in highly polluted areas); with a lower population in the building, this increases the effective ventilation per person.
  • Open minimum outdoor air dampers, as high as 100%, thus eliminating recirculation. (During mild weather, thermal comfort or humidity within a facility normally wouldn’t be affected. During extreme weather, this clearly becomes more difficult to control.)
  • Consider portable room air cleaners with HEPA filters.
  • Consider Ultraviolet Germicidal Irradiation (UVGI), protecting occupants from radiation, which is particularly in high-risk spaces such as waiting rooms, prisons and shelters.

 

 

Developing Solutions

While the experts are recommending the above items, they are not mandatory across the country. States’ policies vary. Not to mention that COVID-19 research is still developing.

 

 

COVID-19 changing building ventilation

 

The result, in the near term, is likely to be a patchwork — some commercial buildings, schools, colleges, and other facilities will make investments, while others will not. One example of an organization making the investment to fight COVID-19 is KIPP DC, a publicly funded and privately operated network of seven school campuses with 1,200 employees and 7,000 students. KIPP DC has taken huge measures, working to find the ideal system optimized to filter the coronavirus.

 

 

KIPP DC’s Coronavirus Filter System (Source)

 

 

Hire Melink to Help

Overwhelmed and not sure where to begin? Melink employs a 100% self-performing, NEBB-Certified national network of Test and Balance (T&B) HVAC technicians that can quickly deploy to assess mechanical systems, verify airflow rates in accordance with ASHRAE 62.1 standards, and perform any traditional T&B work.

We have multiple, long-standing relationships with some of the largest national restaurant, retail, hotel, and supermarket chains. These relationships began because those partners liked the idea of having just one third-party company to coordinate. Melink handles all their properties by objectively verifying that the HVAC systems were installed and are working as expected.

We are here to help you navigate the ever-changing recommendations and regulations of the pandemic. Let us help you keep your doors open while helping protect your employees, customers, and equipment. Contact us.

Coronavirus & Indoor Air Quality

Posted on by Lindsey Burbee

Now, maybe more than ever, many businesses are concerned about indoor air quality (IAQ) to protect employees and customers from coronavirus. With the current spread of COVID-19 across the globe, it is important that we are all taking the necessary steps to reduce the spread of the virus. As part of this, it is important to recognize how your HVAC system can impact your IAQ during long hours of social distancing, as well as steps that can be taken to limit the spread of the virus in buildings.

In a normal year, the typical American spends 90% of his or her time indoors. With current guidelines about social distancing, this number is expected to increase over the next few months. Prior to recent events, the American Medical Association stated they believe 50% of illnesses are caused, or aggravated, by polluted indoor air. Furthermore, per the EPA, indoor air contains two to five times more pollutants than typical outside air.

 

 

Coronavirus
Source: Centers for Disease Control and Prevention

 

So what does this mean for the COVID-19 crisis? Now that we have learned the novel coronavirus can be spread via airborne transmission when in close contact, there is the possibility that the HVAC system could cross-contaminate. That means air from an infected person could recirculate through a facility’s HVAC system and infect another individual. An example of this is how cruise ships experienced severe outbreaks. All cabins share an HVAC system, which is working as a mode of transmission from one individual to another.

While this risk of shared indoor air cannot be completely eliminated,
there are a few items that can be addressed to reduce the potential for
transmission through the HVAC system including:

 

  • Enhanced Ventilation & Ventilation
    Effectiveness
  • Source Separation
  • Air Filtration
  • Operable Windows

First and foremost, facilities should ensure their HVAC
equipment is bringing in the correct amount of outside air required by the
engineered designed plans, as well as managing the pollution and exhaust from
your building properly. To further mitigate this risk, one should attempt to
increase the percentage of outside air being brought into a facility to a
higher percentage than minimally specified. In doing this, the equipment will
reduce the amount of air being recirculated through a building. This will not
only reduce “shared air,” but will also decrease levels of CO2 and other indoor
air pollutants that can create an uncomfortable, or unhealthy, facility.

For a residential facility, where air source isn’t as easily controlled, it can also be helpful to open windows to bring in fresh air to any given room. In addition, it is worth verifying that any fresh air being brought in is being evenly distributed. If it isn’t, certain rooms may have less air turnover, meaning that the air isn’t circulating in and out of the facility properly.

The next few months may be difficult with longer hours than normal spent indoors. It is important that we are all taking steps to minimize the spread of coronavirus and other airborne illnesses both now and in the future. Melink offers products and services specifically designed to track, trend, and improve indoor air quality. Click to learn more about our HVAC test and balance services or PositiV® building health monitor, or contact us today. Our techs are the certified pros in indoor air quality — let us help you mitigate your risk while protecting employee and customer wellness.

Is Your Business Haunted Or Is It Something Worse??

Posted on by Lindsey Burbee

Has your business experienced…

Zombie Levels of Productivity

Poor levels of fresh outside air leading to insufficient IAQ can decrease air quality. According to a study done by Harvard University, productivity levels can be increased by up to 61% when the proper amount of air quality is introduced into the space, and can be increased by 100% when doubling the ventilation.

Chills Running Down Your Spine or Sweaty Palms?

Improper heating and cooling due to an unbalanced building means air is distributed unevenly which creates temperature variation. Hot and cold spots around your building are probably signs of an unbalanced building, or are they??

Something Strange in the Air?

Air drafts can be caused by too much air being delivered to certain areas and then the air moves between rooms in order to reach an equilibrium of pressure.

Musty Odor Means Something Is Lurking

When air isn’t cycled properly through the building on a regular basis and you let the humidity get too high, you provide a breeding ground for bacteria and mold. Considering the average adult spends 92% of their time indoors, that means a lot of time breathing in these gross pollutants!

Mysterious Noises No One Can Explain

Have you been startled by an abrupt sound somewhere in your building that you can’t pinpoint? Poorly sized belts or pulleys can cause RTUs to squeak as they are operating, and duct leakage has been known to create some creepy noises as well.

Doors Opening and Closing With No One There

Pressure differentials caused by an imbalance of air being delivered to certain rooms can make doors open and close on their own.

Don’t call Ghostbusters just yet! There is a good chance you building is not actually haunted but instead just needs a good balance. Many of the above culprits can be easily fixed, and will not only improve your building’s health, but the health and productivity of everyone inside (one study shows estimated productivity benefits from increased ventilation could be as high as $6,500 per person per year!).  Learn more on what a building balance is here or contact us for more information on how to get rid of the pesky (and creepy) issues you are having!

A Balancing Act: Air Balance is an important part of HVAC maintenance

Posted on by Lindsey Burbee

When it comes to HVAC, no news is good news for restaurant facility managers. When you start hearing chatter about the building being hot and humid, drafty, smoky or uncomfortable, you know a problem has already taken root. It’s like a piano being out of tune. In addition to unhappy customers and employees, comfort issues are indicators of energy inefficiency within a system and air balance issues. So, what can facility managers do to prevent comfort and energy threats?

Identifying Common Problems

“Facility managers need to be trained on air balance and push it to their service contractors,” recommends Jeff Dover, resource manager at RFMA.

A good place to start is to gain a foundational understanding of building pressure and common HVAC deficiencies along with following seven easy steps to bring your restaurant back into tune. Most importantly, learn how to look for negative building pressure. Remember, the goal is to stay slightly positive in building pressure.

There are three methods to identify negative building pressure. The first and most reactive method is to monitor signals that your building is negative. These signs are hot/cold spots, entry doors that are hard to open, poor smoke capture, humidity, condensation dripping from diffusers and drafts.
Second, you can measure the building pressure yourself or with the help of your service contractor by using a pressure reading tool such as an anemometer to get a ballpark pressure reading. The third and most accurate method is to hire an air balance firm to check the facility’s building balance once a year. If comfort-related issues or a negative building pressure reading are observed, then an air balance needs to be scheduled.

Investigating the Cause

What causes a building to become negative or unbalanced? The usual offenders are equipment deficiencies, improper preventative maintenance programs, and adjustment errors such as kitchen staff fiddling with thermostats or service contractors opening or closing dampers.

 Here are 10 example deficiencies you or your service contractors should be on the lookout for:
  1. Exhaust fans in poor condition
  1. Supply air leaking above ceiling
  1. OA dampers improperly installed
  1. Exhaust fans not sealed to curb or hinged correctly
  1. Dirty compartment/coil in the RTU
  1. Tops of diffuser not insulated
  1. Filters improperly sized for hoods
  1. MUA not operating properly
  1. Dirty indoor/outdoor filters
  1. Worn/broken belts

Achieving Air Balance in HVAC

Once you’re ready to bring a facility back into tune, there are seven easy steps to complete. These steps may be completed by the facility manager alone, but are more likely in partnership with a service contractor. To get started, pull out the facility’s previous balance report to use as a base line for data.

One Principal Engineer at a hamburger fast food chain overseeing thousands of locations explains how her team uses the air balance report to get started with troubleshooting comfort issues.

“The reports really are my first line of defense when someone says ‘Hey, my store is cold/hot/humid,’ she points out. “The first thing I do is pull out the TAB report and see what it says. I look at the punch list and ask was anything wrong? Not fixed? It helps when I have to remotely assess or diagnose problems.”

7 Steps to HVAC Balance

Whether the previous air balance report has been reviewed or not, proceed to the following steps:

  1. Ask the onsite restaurant managers what the complaints are from employees and customers.
  1. Turn on all HVAC equipment.
    • Verify thermostats are set to “FAN ON”
  1. Check building pressure with the flame test in different areas around the restaurant (Figure 3)
  1. Observe smoke capture
    • Is the hood in the correct overhang position?
    • Are there drafts along the cook line?
  1. Check for common comfort issues (hot/cold spots, entry doors that are hard to open, poor smoke capture, humidity, condensation dripping from diffusers and drafts).
  1. Inspect the equipment.
    • Are the filters clean?
    • Are the belts in good condition?
    • Are the exhaust fan wheels clean?
  1. Determine an intervention plan.
    • If some preventative maintenance actions and/or repairs need to happen, start with the service contractor.
    • If equipment is inoperable, have it repaired or replaced.
    1. If the preventative maintenance actions are in order and the problems persist, call in a certified air balance company that has experience with restaurants like yours.
Facility managers need to trust that their service contractors will notify them of airflow-related issues. Those technicians are out on the roofs and looking at the HVAC system components more than anyone else. If the restaurant has negative pressure or other out-of-tune symptoms, the service contractor needs to inform the facility manager right away. After all, you want your customers and employees to continue singing your praises. 
Air Balance in HVAC

3 Steps to Troubleshooting Your Facility’s HVAC With Onsite Staff

Posted on by Lindsey Burbee

HVAC Troubleshooting

Have you identified that your facility is experiencing a potential air balance problem?  You might be experiencing hard to open doors, uncomfortable temperatures, poor smoke capture, odors, drafty areas, or any combination of the other common sick building symptoms.  The inevitable question now is, “Who can resolve this best?” Bringing in your facility’s mechanical contractor may be your first instinct but troubleshooting with your onsite managers is actually the best place to start. Work through the following questions with your facility’s day-to-day manager:  

1.  Is the equipment running?

As basic as this may come across, it is absolutely crucial to check if all HVAC equipment is operating. Check grilles to see if air is being blown out or sucked in. Check roof equipment, can you hear the fans from the RTU, MUA, or EF units spinning? Have the manager record and communicate findings.

2. Check the Thermostats

Navigate to the wall mounted thermostats and ensure they have the proper set points. Often, a thermostat is installed and connected to the system and then left alone. When this occurs the thermostat is left at factory settings which is often set at a random temperature. Your staff can follow the directions on this thermostat to program it for the desired temperatures.  As well, check the thermostats for “Fan ON.”

Thermostat

3.  Check the Circuit Breakers

Check indoor and outdoor circuit breakers. Observe tripped or “Off” breakers. DO NOT flip the breaker on. If tripped or left off, there’s likely a reason for it and you don’t want to risk frying the electrical systems. We recommend calling an electrician for this type of deficiency.

 

Armed with your findings from these simple tests, you can save some money with a Do-It-Yourself fix.  It’s possible that the journey back to a healthy building ends here.  But if the problem persists, it’s time for the level of technical know-how. Call the mechanical contractor. With your observations to these preliminary steps above, you can approach your mechanical contractor with information that will help them to better understand your situation and get you closer to achieving a healthy building.