Access Sensor Technologies

Estimating sample mass A blog post describing procedures for estimating the mass of particulate matter that will be collected during a sample.

Read our new blog to learn how to answer these Q's:
Should I use the 1 or 2 L/min PM2.5 inlet? What's the lowest PM concentration I'll be able to quantify given my sample LOD, flow rate, & duration? How long will it take to collect a sample mass > my LOD? www.accsensors.com/blog/estimat...

Sample quality assurance A blog post that describes how to perform quality assurance checks on filter-based particulate matter samples.

Our latest blog post includes guidance for performing quality assurance (QA) checks on particulate matter samples. Some of this advice is specific to working with the UPAS or Home Health Box, but most of these QA steps apply to samples collected with any instrument.
www.accsensors.com/blog/qa

YouTube video by Access Sensor Technologies Using AST's Filter Cartridge Opening Tool

What do I do with this filter cartridge opening tool?
youtube.com/shorts/6l4E3...

YouTube video by Access Sensor Technologies How to check the UPAS sample flow rate against an external flow meter

Looking for advice on how to check the UPAS sample flow rate against an external flow meter? Check out our new video on YouTube!
youtu.be/WA94fYv0oaU

We’ve released another firmware update for UPAS v2.1 and v2.1 PLUS. We encourage users to update to firmware rev206. Read this blog to learn more about the associated improvements, including expanded microSD card compatibility checks and Power Save mode bug fix.
www.accsensors.com/blog/upas-fi...

Thank you to Jess Tryner at Access Sensor Technologies for giving a cool and engaging presentation at the American Association of Aerosol Research earlier this week! We are so excited to continue collaborating together on our new projects in indoor air pollution research.

American Association for Aerosol Research 43rd Annual Conference, October 13-17, 2025, Buffalo Convention Center, Buffalo, NY

We’ll be at #AAAR2025 next week!

Closing out an inspiring week at ISEE/ISES 2025 in Atlanta! We are grateful for the chance to connect, share our research, and learn from such an impressive roster of conference attendees. Thanks to all who stopped by our posters. See you next year!

Flash Talk FT06-06 at 16:33 in Regency VII Familial Differences in Personal PM2.5 Exposure Explained with Spatiotemporal Exposure Apportionment

P07-07 Air Quality in an Agricultural Setting: A Community-Engaged Research Study

P15-02 Cross-Sectional Association Between Household Air Pollution Exposure and Blood Pressure Amongst Adults in Rural Rwanda, East Africa

Today at #ISESISEE2025, the following presentations are on studies that used our UPAS:
1. Poster P07-07
2. Poster P15-02
3. Flash Talk FT06-06 at 16:33 in Regency VII

A graphic advertising the joint ISES-ISEE conference in Atlanta, Georgia, USA from August 17-20, 2025.

We’ll be at #ISESISEE2025 in Atlanta next week and hope to see you there!

Will my UPAS log files change substantially if I update to the new firmware (rev200)? Nope! The log file format will remain the same. Read any UPAS log file into R using our astr package. Install astr v2.3.0, which we just released along with firmware rev200: www.github.com/accsensors/a...

Introducing the new UPAS v2.1 and v2.1 PLUS firmware A blog post describing new features included in a major Ultrasonic Personal Air Sampler (UPAS) firmware update released in 2025.

What’s new in the new UPAS firmware? The UPAS now gets UTC time from the mobile device used to program the sample. No more going outside to get a GPS signal if your UPAS loses track of the time (in most cases, at least)! Read our latest blog post to learn more: www.accsensors.com/blog/new-fir...

UPAS v2.1 The UPAS v2.1 is quiet, wearable, easy-to-use particulate matter sampler that logs time-resolved location, light, motion, T/P/RH, and sample flow data.

We’ve released a new UPAS v2.1 and v2.1 PLUS User Guide that describes operation with the new firmware (rev200+). Download it from our website! Still running an older firmware version (<= rev157)? Don’t worry. The user guide for that firmware is still up too!
www.accsensors.com/upasv2.1

Access Sensor Technologies: Products Learn more about our virtually-silent, portable, and easy-to-use air pollution samplers.

Can I update any UPAS to the new firmware? Any UPAS v2.1 or v2.1 PLUS can be upgraded to firmware rev 200. These devices have serial IDs that start with “PSP”. UPAS v2.0 cannot be upgraded to the new firmware. Which UPAS is which? See our Products page to learn more: www.accsensors.com/products

Introducing the new UPAS v2.1 and v2.1 PLUS firmware A blog post describing new features included in a major Ultrasonic Personal Air Sampler (UPAS) firmware update released in 2025.

We’ve released a major firmware update for our UPAS v2.1 and v2.1 PLUS. This update makes sample setup easier and UPAS operation more reliable! Read this blog to learn more about what’s new and how to update your UPAS: www.accsensors.com/blog/new-fir...
#AirPollution #AirQuality #ParticulateMatter

A graphic that says we’re exhibiting at the Air & Waste Management Association Air Quality Measurements Conference that will take place on April 23-25, 2025 in Aurora, Colorado.

We’ll be exhibiting at the Air & Waste Management Association Air Quality Measurements Conference in Aurora, CO this week! Come by Booth 12 and say hello! Find out if our UPAS or Home Health Box can fulfill your air sampling needs! #AQMeasurements

Energy Institute Cogen Summer Internship - Energy Institute The 2022 Cogen Summer Interns and Fellows. This could be you! Energy Institute’s Cogen Summer Internship Summer 2025May-August The Energy Institute is partnering with local companies to create interns...

We’re looking to hire 1-2 summer interns through the CSU Energy Institute’s Cogen Summer Internship program. Interns will work on R&D activities related to our wearable #airpollution samplers. $25/hour, 40 hr/week for 10 weeks. Apply here by March 2nd: energy.colostate.edu/energy-insti...

Application and validation of a wearable monitor for assessing time- and location-resolved exposures to particulate matter in California’s Central Valley Reliable assessment of personal exposure to air pollution remains a challenge due to the limitations of monitoring technology. Recent technology developments, such as reductions in the size and cos...

Published today! Hundreds of 24h personal & indoor PM2.5 & PM10 measurements collected at 2 LPM with UPAS compared to samples collected with PMIs + Apex2 pumps: Spearman correlation > 0.8, normalized mean difference < 16%. All samples collected in California’s Central Valley.
doi.org/10.1080/0278...

Want to write one of these papers? Need some cool new portable instruments to collect the data? Just let us know! #airpollution #airquality

GitHub - accsensors/astr: astr package for R log file analysis astr package for R log file analysis. Contribute to accsensors/astr development by creating an account on GitHub.

We just released a new version of our astr package for reading UPAS and HHB log files into R! What’s new? This version won’t throw an error if you try to read an empty sample log; it will just return a data frame with zero rows. I stall from GitHub! #airquality #Rstats github.com/accsensors/a...

UPAS v2.1 PLUS The UPAS v2.1 PLUS combines a quiet, wearable, easy-to-use particulate matter filter sampler with time-resolved location and pollution sensors.

We just posted an updated UPAS v2.1 and v2.1 PLUS User Guide. What’s new?
1) An improved explanation of what happens when you start a sample from the app
2) advice for preparing the internal Li-ion battery for shipping or long-term storage. Download from this page: www.accsensors.com/upasv2.1plus

Choosing the best particulate matter sensor duty cycle for your measurement application Guidance for UPAS v2.1 PLUS users on selecting the best time-resolved particulate matter sensor duty cycle for a specific air sampling application.

You can program the PM sensor in the UPAS v2.1 PLUS to operate on a duty cycle so the UPAS can run longer on a single battery charge. Looking for advice on selecting the best setting for your application? Read our new blog post! #airquality #airpollution www.accsensors.com/blog/duty-cy...

Hello, Bluesky! Want to hear about new publications featuring our products? See blog posts with advice for collecting air samples? Find out about firmware and software updates? Follow us!