Ambient Air Monitoring
Hygieneering conducts property line nuisance dust assessment for clients to evaluate ambient dust concentrations leaving their property. Sampling is focused on single sources, as snapshots of contaminant concentrations are collected over several short (24-hour) periods of time. The particulate matter (PM) data collected from these studies are compared to the National Ambient Air Quality Standards (NAAQS) established by the United States Environmental Protection Agency (USEPA). Under the Clean Air Act, the USEPA established NAAQS for conventional pollutants, including particulate matter (PM). The NAAQS includes both primary and secondary standards for PM, such as 35 ug/m3 (24-hour) for PM 2.5 and 150 ug/m3 (24-hour) for PM 10. Primary NAAQS are health-based standards intended to “provide public health protection, including protecting the health of “sensitive” populations such as asthmatics, children, and the elderly. Secondary standards provide public welfare protection, including protection against decreased visibility and damage to animals, crops, vegetation, and buildings.” (US EPA, 2018a)
The NAAQS standards were developed to assist in evaluating air quality on a regional basis and were not intended for single source emission limited for properties. However, there are no quantitative PM limits that are directly applicable to these data. Therefore, NAAQS levels are used only for reference or benchmark comparisons to assist in site recommendations and data evaluations for Hygieneering clients looking to improve and evaluate dust emissions from their operations or site.
At the state level, 35 Illinois Admin. Code Section 212 addresses emissions of particulate matter. The only standard applicable to fugitive emissions of particulate matter from this source are found at 35 IAC 212.301, which states: “No person shall cause or allow the emission of fugitive particulate matter from any process, including any material handling or storage activity, that is visible by an observer looking generally toward the zenith at a point beyond the property line of the source.” Hygieneering conducts visual observations while onsite to comply with this code.
Conducting the fugitive dust study involves the use of TSI DustTrak DRX weather-resistant enclosures that are set to data log for 24-hour periods, particulate matter size 2.5 and 10, as used by the USEPA for National Ambient Air Quality Standards. The DustTrak DRX units provide real-time dust monitoring that simultaneously measures both mass and size fraction. The DustTrak DRX monitor uses light-scattering laser photometers that provide real-time aerosol mass readings and data logs. The instruments subdivide the concentration of dust by particle size with the following breakdown: Total, PM 10, Respirable, PM 2.5, and PM 1. Hygieneering can also conduct ambient air monitoring for respirable crystalline silica including all three (3) forms (quartz, cristobalite, tridymite) using active sampling methods for 8-hour periods to determine if silica dust is present, and leaving the site, per clients request. Other requests include the use of weather stations that can collect, rainfall amount, temperature, and most important wind speed and direction during the sampling periods. Typically, two (2) to four (4) dust monitoring enclosures are set up around the property line and monitored over several days, during dry periods with little to no rain, to get representative data collection for this type of study.
Hygieneering has been assisting with dust monitoring with clients in many industries including mining, construction, general industry, and even in healthcare during renovation projects. If you have a demolition project, renovation work, or need to assess your operations fugitive dust emissions, this type of study may be valuable for your company.
