If you have never had your indoor air tested, you probably have questions about what the process looks like. Here is what happens, step by step, in a Baseline assessment.
Before the Assessment
There is no prep required. Live in your home normally. Run your HVAC as you usually do. We want to measure your home's air under your actual conditions, not under staged conditions that look good on paper.
The assessment is scheduled for about 90 minutes. Bryan conducts every assessment personally. This is not a technician visit. It is a measurement session run by someone who has been inside hundreds of Los Angeles homes and knows what the local data patterns look like.
What Gets Measured
Six parameters, every time.
PM2.5: fine particulate matter, measured in micrograms per cubic meter. The equipment is a laser particle counter, not a consumer-grade sensor. It reads in real time and distinguishes between particle sizes.
CO2: measured with a non-dispersive infrared sensor. We take readings in occupied rooms, bedrooms, and common areas. The goal is to see how CO2 builds during occupancy and whether the home is diluting it effectively.
VOCs: total volatile organic compound levels, measured in parts per billion. We look for baseline levels and spikes related to materials or activities.
Humidity: relative humidity, measured room by room. We are looking for the 40 to 60% target range and for variation between spaces.
Temperature: again, room by room. We are checking distribution, not just the thermostat setting. A 3 to 4 degree spread between rooms means the HVAC system is not delivering evenly.
Ventilation rate: estimated from CO2 decay curves and building characteristics. This tells us how much fresh air the home is actually receiving per hour.
What Else We Look At
Beyond the instruments, the assessment includes a visual inspection of filtration and airflow components. We check filter condition and fit, duct register placement and airflow, exhaust fan function in kitchens and bathrooms, and any visible signs of moisture intrusion.
The filter fit check alone is worth the visit. Roughly half the homes we assess have gaps around the filter frame that let unfiltered air bypass the media. It is the single most common issue we find, and it is usually the easiest to fix.
What You Get
Within a few days, you receive a Baseline Report. It includes your readings for each parameter, your composite Baseline Score (weighted across all six measurements), a comparison to EPA, WHO, and WELL Building Standard thresholds, and a prioritized recommendation list ranked by impact.
The Baseline Score weights PM2.5 at 30%, CO2 at 25%, and the remaining parameters make up the balance. Most LA homes score between 40 and 60. The national average is about 55.
The recommendations are specific. Not "improve your ventilation" but "run your HVAC fan in 'on' mode during occupied hours to increase air mixing" or "seal the filter frame gap on the return plenum."
What It Does Not Include
The assessment is not a sales call. There is no equipment pitch during or after the visit. The report gives you data and recommendations. What you do with them is up to you.
If you want ongoing monitoring or managed service after the assessment, Baseline offers membership tiers that include continuous sensors, filter service, and seasonal adjustments. But these are separate conversations that happen after you have your data, not during the assessment.
What It Costs
$195. That covers the assessment, the equipment, the analysis, and the scored report. About 90 minutes of time in your home.
If you want to understand what the numbers mean before testing, our free IAQ guide is a good starting point. It covers the thresholds, the science, and what to look for in your own home.