Filter Express LLC

02/24/2021

During the pandemic, germicidal ultraviolet light (UV-C) energy for surface and air inactivation has generated much interest and many questions that ASHRAE aims to answer.

08/06/2020

COVID-19 & HVAC Systems
CDC has not posted guidance on the decontamination of building HVAC systems potentially exposed to SARS-CoV-2. To date, we have not identified confirmatory evidence to demonstrate that viable virus is contaminating these systems. Should such systems actually become contaminated with viable virus, the most likely scenario is believed to be that the deposited virus would lose its viability naturally within hours-to-days, and thus, there is no guidance advocating proactive system shutdown for decontamination and/or filter exchange.

The 3 hour reference that is sometimes reported, is a misunderstanding of data resulting from a recent NIH-led experiment where intentionally aerosolized SARS-CoV-2 virus remained viable in aerosols throughout the duration of the experiment. There was still viable virus in the air at the conclusion of the 3-hour experiment. The same researchers determined that the half-life for the intentionally aerosolized virus was 2.7 hours. It is important to note that it is not yet known if naturally-aerosolized SARS-CoV-2 virus would behave similarly. It is also important to note that to date, infectious SARS-CoV-2 virus has not been isolated from aerosol samples collected in the treatment rooms of patients with COVID-19.

So how does this information affect HVAC technicians? There should probably be screening questions asked of the residence occupants prior to arrival, similar to those asked of international travelers arriving at U.S. airports. If there is no reason to suspect that the occupant may be infected with COVID-19, then the HVAC technician may reasonably conduct the repair/maintenance activities using the same social distancing rules they would use in the general community.

If there was reason to suspect the residence may have recently been occupied by a known/suspected COVID-19 positive person, then it is reasonable to suggest some period of time for the residence to remain vacant prior to entry by the HVAC technician. The exact amount of time would vary considerably, based upon a multitude of factors related to the infected person(s) and the residence design/operation.

One approach might be to use the guidance for re-entry that is posted by CDC for Cleaning and Disinfection for Community Facilities. This guidance suggests opening outside windows and doors to ventilate the area and waiting 24 hours or as long as practical before re-entering the area to begin cleaning and disinfection.

Using similar logic, an HVAC technician entering a residence previously occupied by a person with known/suspect COVID-19 disease might use a similar waiting period, then utilize appropriate gloves, shoe covers, eye protection and a face covering prior to entering the residence for HVAC repair.

It’s important to note that in this circumstance, the face covering is not intended for respiratory protection, but is intended to assist the technician from inadvertent touching of their face. If available, an N95 or greater respirator, used in conjunction with an OSHA-compliant respiratory protection program, could be used instead of the face mask.

07/25/2020

When all fingers point to the technician, use the following process to troubleshoot and resolve HVAC problems. They will prove your design and improve system performance.

07/24/2019

04/06/2018

Freelancers and independent contractors will see changes to tax rates and deductions next year, with some mandates still in effect now.

03/07/2018

Have a business problem you just can't crack? You can

03/07/2018

Writing a business plan doesn't have to be daunting. Here's what you need to know about getting started with a strategy for your company.

03/07/2018

If you're ready to move beyond the basics with your sales strategy, consider these out-of-the-box ideas to boost revenue for your small business.

02/01/2018

The right paid search ad can generate sales overnight. But a poorly executed campaign will result in wasted ad spend and zero results.

01/30/2018

29 years of serving our customers. Thank you for you support

01/21/2018

The occasional unhappy customer comes with the territory. These tips will help turn an unpleasant situation into a win for your small business.

01/18/2018

With a new focus on posts from friends and family, Facebook makes it much harder for small businesses to reach customers on social media.