Set up a CO2 monitor lending program at your library

Practical information

This page has practical info for libraries: finding partner organizations and funders, buying and recalibrating CO2 monitors, and evaluating your program.

Look for handouts, infographics, and other patron-directed information on the patron info page.

Questions to consider for your local context

Find partner organizations

Consider collaborating with other organizations to maximize the reach and impact of your library's CO2 monitor lending program. Equity isn't just about offering free services but also about reaching people where they are!

Choose CO2 monitors

CAVI's founders are personally familiar with two CO2 monitors: the Aranet 4 and the CO2 Check. Others are available; we recommend an NDIR sensor (that means non-dispersive infrared sensors). Some questions to keep in mind:

You may find it useful to read this detailed report by researchers from Universidad de Castilla-La Mancha (ICCA-UCLM), Asociación Mesura, University of Colorado at Boulder, and Fundación CEAM:

Villanueva et al., 2021. "Guide about affordable CO2 detectors for COVID-19 prevention." 

Calibrate CO2 monitors

The devices you use will come with calibration directions. Generally, you'll calibrate the device by exposing it to outdoor air, where the CO2 ppm is expected to be at steady level close to 420 ppm. You can decide if you want library staff to calibrate sensors routinely, or if you will leave it to patrons to calibrate the sensor when they borrow it.

Buy CO2 monitors

In the United States, Aranet has offered libraries a Buy 2 Get 1 Free program; contact Nicole White.

In Canada, Aranet's distributor Prescientx has offered libraries a Buy 2 Get 1 Free program; contact Barry Hunt.

Evaluate your CO2 monitor lending program

CAVI is developing an evaluation toolkit to measure use of library CO2 monitors and to assess patron satisfaction and environmental health literacy. 

Find funders

Can your collection development budget or your Friends of the Library group support a CO2 monitor lending program without external funding?

The US National Network of Libraries of Medicine has seven Regional Medical Libraries, each of which offers grants. NNLM wants to support library-public health department collaborations.

The US Institue of Museum and Library Services (part of the federal government) has several grant programs related to the pandemic.

Professional associations


Want another pair of eyes on your grant application related to CO2 monitors in libraries?

We'd be happy to read your funding proposal. 

What about indoor air quality inside our library?

It would be great to use your CO2 monitors to measure your library's indoor air quality and take action -- perhaps increasing ventilation or adding filtration. You can use the same curated information that you recommend to patrons.

Some venues display live information about CO2 levels in their spaces and on websites. This would be a great advertisement for your library's CO2 monitor lending program!

If you're interested in displaying live CO2 ppm data, you'll want to keep this feature in mind when you are choosing your monitors.