Jun

15

2020

Building readiness: How to implement the CDC's new HVAC/plumbing guidelines

Many Texans and Arizonans will return to the office in the coming weeks, but their workspaces may not look the same as they did before COVID-19 hit in February. Offices will be redesigned, some employees may work from home full-time, and the gears that keep the building running will have to adapt to these changes. Some companies will inspect their systems; others will upgrade them; and more will look for larger renovation/new construction options to better support their workforce.

To prepare for this new normal, the Center for Disease Control and Prevention (CDC) recently released its guidance for reopening businesses. While all the measures outlined in this document are essential in the fight against COVID-19, this blog will focus on recognized HVAC and plumbing standards and recommendations.

TDIndustries Mechanical Engineer Esmeralda Morales provides these snippets from the CDC’s release, and a few thoughts to consider when planning your building readiness strategy. (Note: all quotes are directly from the CDC release here.)

“Ensure that ventilation systems in your facility operate properly. For (HVAC systems) that have been shut down or on setback, review new construction start-up guidance provided (by ASHRAE).”

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  • Prepared for full speed: With so many employees working from home, it’s likely that air conditioning systems have been operating at reduced capacity or even partially shutdown. Now that your occupants are ready to come back, these systems must be readied for operation. We suggest checking these systems at least two weeks before the planned return-to-office date to allow for necessary repairs and maintenance.
  • Legionella test: Plumbing systems are designed to ensure proper water circulation and temperature setpoints. Reduced occupancy may create favorable conditions for another deadly disease, Legionella. Legionella colonizes between 77-108 degrees Fahrenheit, and when buildings experience low domestic water flow, water becomes stagnant, leading to a perfect breeding ground for Legionella. We recommend flushing your plumbing systems at all points of use and to confirm domestic water heating systems are operating above 120 degrees Fahrenheit. For hydronic systems, a certified inspector can confirm your facility is free of this harmful disease and others.
  • Downtime improvements: While many businesses hope to return to the office soon, the downtime offers an opportunity: uninterrupted time for an upgrade, renovation, or changeout. There are many ways to battle COVID-19 and other diseases. Increased ventilation, mechanical filters, ultraviolet technology, and other technologies can all be effective. What works best for your business? HVAC specialists can help you make the right choice and maximize this downtime.

“Increase circulation of outdoor air by opening windows and doors, using fans, and other methods.”

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  • Air quality improvement: For various reasons, most companies do not have functioning windows, but there are alternatives for incorporating outdoor air. Dedicated outside air systems (DOAS) can provide better ventilation using separate cooling functions to improve indoor air quality. These systems can also reduce energy use. If your schedule and budget allow, consider this option.
  • Verify controls compatibility: Your first idea may be to increase economizer modes up to 100 percent to increase outdoor air flow. The HVAC system may not be designed to operate at these conditions. If your building is going to be partially occupied, engage a Professional Engineer to help determine the correct quantity of outside air that can be delivered under multiple system operational scenarios. This process may require a controls contractor to modify your building management system to support these new pandemic mode parameters. Their goal will be to establish sequences to prevent losing control of building humidity and temperature due to the increased outside air loads. The CDC recommends disabling demand-control ventilation, but before doing so, building owners should consider engaging a qualified controls contractor to perform these changes.

“Evaluate the building and its mechanical and life safety systems to determine if the building is ready for occupancy.”

  • Hazard check: In addition to the virus/bacteria growth listed above, mold, rodents, and other stagnant water system problems can create additional health issues for your returning occupants. Consult necessary professionals to identify these hazards first, then seek advice from a HVAC/plumbing specialist.
  • Increase filtration: For air-side filters, consider increasing along the MERV (minimal efficiency reporting value) scale. This suggestion must be balanced with the potential for diminishing airflow. Engage a Professional Engineer to evaluate this strategy. Inspect filter housing and racks to minimize filter bypass. Filters should fit snugly.
  • ‘Clean’ ventilation zones: Air flow should begin in occupants’ area of work and flow toward designated high-risk parts of the building. This will flow all potential contamination away from your employees. A professional engineer can help identify solutions.
  • Portable filtration: HEPA (high-efficiency particulate air) fans and filtration systems can be a quick, effective solution in high-risk areas. When paired with other solutions, this can greatly improve your facility’s performance.

Interested in learning more? TD recently held an in-depth webinar on COVID-19 indoor air quality technologies. To view it, click the button below.

WEBINAR: Best Practices of Indoor Air Quality in the Wake of COVID-19View IAQ technologies cut sheet 

Categories: COVID19   Facilities   plumbing   HVAC   IAQ