How HVAC Systems Help Reduce Potential COVID-19 Exposure: As the economy begins to reopen and we return to our buildings, what role do building ventilation systems play in reducing our risks of infection? Infection via inhalation or contact with droplets is well understood at this point. Another potential exposure route being discussed is exposure via

I’ve lived in California for over 30 years. Most of that time I never really thought about wildfires; their destructive flames seemed only possible in the movies. That has changed, not just for me, but for most Californians, who have become brutally aware of the very real threat wildfire poses. While fire itself is by

Air Quality Index (AQI) and You During the 2018 Paradise Fire smoke wave, many in the Bay Area obsessively checked online for air quality information and updates. Here is an overview of a handful of real-time air quality websites I found helpful and how they compare. Keep in mind that climate change plus newer and cheaper

DIY Box Fan Filter & Air Quality Experiment Here in San Francisco and surrounding areas kids are stuck indoors during this smoke wave caused by our wild fires with little or no air filtration. In San Francisco the school buildings are older and are not setup to have building wide air filtration. Nor can cash-strapped

Bay Area Wildfire Smoke and Indoor Air Quality I am writing this on November 13, 2018.  For the past week the state of California has been cloaked in thick, noxious smoke from the wildfires burning out of control.  Northern California is mostly affected by the Camp Fire near Chico, CA and Southern California by the

With the legalization of marijuana, some black-market growers are abandoning their illegal cannabis grow operations. Grow ops, often set up in rented properties, can leave a mess for landlords to clean up. Many of these properties are put up for sale and then become the responsibility of the home buyer. Identifying a grow op is 

Effects of Airtight Construction on Lab Pressurization Most labs and clean rooms require airtight construction to create differential pressure with respect to adjoining spaces. Labs are usually maintained at slightly negative pressure to keep the chemicals used in the labs from migrating to adjacent spaces. Clean rooms, on the other hand, have to be kept