Post by Nadica (She/Her) on Sept 1, 2024 3:54:47 GMT
CO2 sensors: Vitalight and Aranet4 review - Published July 25, 2022
Covid is airborne; that means you catch it by breathing air shared with an infected person. It’s in people’s exhales. Another thing in people’s exhales is an odorless, colorless gas called CO2. You breathe in oxygen, your body enjoys it, then your blood carries what's left as CO2 to your lungs, and then you breathe it out.
This is why you’ve probably seen some people carrying around little air sensors that measure CO2 — they are keeping an eye on how full a room is getting with people’s exhales. The higher the sensor readings, the higher of everyone’s chance of getting infected.
Since many people spread it without knowing they have it (6 of 10 people are asymptomatic), hardly anyone is masking, and the most infectious variant yet is ravaging our communities, measuring CO2 is a reliable way of knowing when a room, commuter train, or other enclosed space becomes covid-unsafe. And personally, I don’t want to find out firsthand what the lived experience of long covid is like.
Portable CO2 monitors are an important safety tool to be used in combination with masking and vaccination. Until recently, they’ve been bulky, too complicated for non-technical people to use, and too expensive. That fancy Aranet4 you see all the covid-aware geeks using to stay safer? It’s $249.00 on Amazon. That’s out of reach for most people, especially those being put at most risk with this disease, like front line and service workers, and kids being sent to maskless, unventilated classrooms.
I was lucky that a reader here recently bought me an Aranet4, but I’ve been low-key about my use of it because I don’t think it’s fair that the people who can’t afford one need them the most. So when I saw that a low-cost portable CO2 monitor came out a few weeks ago, the Vitalight Mini ($39), I jumped at a chance to test and review it.
My conclusion? Get a Vitalight Mini, and get it ASAP. Inexpensive, very portable, easy to see in the dark, and though slightly less precise than the Aranet4 it lets you see immediate changes in CO2 -- and alarms go off when dangerous levels are hit.
Caveat: I haven't had it long enough to know what its (USB-C charging) battery life looks like.
Aranet4 vs. Vitalight Mini
The Vitalight Mini arrives pre-charged in a box with a USB-C cable and an instruction manual. It is a small, thicc, lightweight device with a comically large snap clip attached. Mine was almost fully charged. It has just one button and a lit screen, with air sensor holes on the sides and back (the back are the main sensors).
One long-ish press and the Vitalight turned on with a loud beep that startled me! The Vitalight has a neat feature where when the CO2 goes over 800, aka you’ve hit the danger zone, it beep-beeps an alarm to tell you. The beep can also be turned off by simply clicking the button twice. Two clicks turns it back on.
The Vitalight Mini’s brochure has a handy guide to its color-coded levels: Green (400-800), Yellow (801-1200), Orange (1201-1500), and Red (1501-5000). Here in San Francisco where we’re at sea level the normal reading outside in fresh air on my Aranet4 is always around 450. In my apartment where I live alone and like to keep windows open, I’m used to seeing a reading between 475-500.
I was pleased to see the Vitalight Mini was charged and ready to go when I turned it on. (24 hours later it had gone through 2 of 4 battery bars.) The instructions say to wait 35 seconds for it to calibrate — but even after that I noticed the Vitalight was at 400 while the Aranet was hovering at 460-470. So I followed Vitalight's instructions to do a manual calibration.
This involved button presses to get into a menu then waiting through a countdown of 200 seconds. But nope, it didn’t change: the Vitalight Mini was still showing me 50-60 lower than the Aranet. For most everyone using this for covid risk assessment, the 50-60 range is not a significant margin. But I wanted to see if that margin was consistent over time and over battery life, and if it was consistent at both high and low readings.
I checked the Vitalight Mini versus the Aranet every few hours for the rest of the day, through the night (I don’t sleep at night), and in the morning and afternoon before taking it out. The 50-60 reading being less than the Aranet’s reading remained a consistent difference.
Before taking both sensors out into the wild I wanted to make a safety alteration to my Aranet: I needed to be able to hold both in one hand while I photographed the readings side-by-side. I solved this by adding a finger loop to the back, one of those cheap adhesive finger straps sold for phones.
I made sure to only adhere it to the Aranet’s battery cover and not over any sensors. It now allows me to hold the Aranet4 more securely in one hand, and I highly recommend adding a "phone grip" if you can.
My first stop was Walgreens on Castro Street at 18th. They had the front doors open but no other ventilation I knew about. Most of the employees were masked but only about 1/4 of the customers were.
And it showed on my CO2 monitors. Within two minutes the Vitalight went from 400 to 666, while the Aranet went from 450 to 733. This is not a place anyone should be without a mask while San Francisco is in a six-week-and-counting BA.5 surge.
The Vitalight’s alarm went off at 800 (beeping twice) as its arrow moved from green to yellow. The Vitalight number raced higher and the Aranet refreshed again — now closer to the Vitalight. The Vitalight’s two-beep alarm went off again as its risk category arrow moved to Orange. I was ready to flee but waited for the Aranet to refresh — and then it did, at a higher number than the Vitalight, having overtaken it. The numbers kept going up but I bailed. I had what I needed.
The Aranet’s readings were more precise, but delayed, and there is no alarm to warn me. The Aranet is top of the line and excellent for precision, and its app is not just convenient abut an excellent tool for getting all the data you need, as well as data over time (and keeps a history of readings).
The Vitalight has an acceptable margin of error for an everyday user going to school, the store, taking the bus, going to the dentist, etc. The Vitalight showed me I was in danger much faster than the Aranet4, and that’s a huge advantage, although the accuracy gap seemed to increase as CO2 got worse — but after two alarms you should be getting TF out of there anyway.
The alarms are a huge bonus: if you’re not paying attention, this device will let you know the air is unsafe now. It will be an interesting dynamic when multiple people at a conference (or kids in a classroom) all have alarms go off warning the entire room about toxic air.
Ask me any questions in the comments, or give me suggestions or advice, too! I’m constantly looking for tips and trying to learn how to stay safer, better. Thank you for reading.
Stay apart, stand together, mask up, and stay strong.
xo,
Violet
Covid is airborne; that means you catch it by breathing air shared with an infected person. It’s in people’s exhales. Another thing in people’s exhales is an odorless, colorless gas called CO2. You breathe in oxygen, your body enjoys it, then your blood carries what's left as CO2 to your lungs, and then you breathe it out.
This is why you’ve probably seen some people carrying around little air sensors that measure CO2 — they are keeping an eye on how full a room is getting with people’s exhales. The higher the sensor readings, the higher of everyone’s chance of getting infected.
Since many people spread it without knowing they have it (6 of 10 people are asymptomatic), hardly anyone is masking, and the most infectious variant yet is ravaging our communities, measuring CO2 is a reliable way of knowing when a room, commuter train, or other enclosed space becomes covid-unsafe. And personally, I don’t want to find out firsthand what the lived experience of long covid is like.
Portable CO2 monitors are an important safety tool to be used in combination with masking and vaccination. Until recently, they’ve been bulky, too complicated for non-technical people to use, and too expensive. That fancy Aranet4 you see all the covid-aware geeks using to stay safer? It’s $249.00 on Amazon. That’s out of reach for most people, especially those being put at most risk with this disease, like front line and service workers, and kids being sent to maskless, unventilated classrooms.
I was lucky that a reader here recently bought me an Aranet4, but I’ve been low-key about my use of it because I don’t think it’s fair that the people who can’t afford one need them the most. So when I saw that a low-cost portable CO2 monitor came out a few weeks ago, the Vitalight Mini ($39), I jumped at a chance to test and review it.
My conclusion? Get a Vitalight Mini, and get it ASAP. Inexpensive, very portable, easy to see in the dark, and though slightly less precise than the Aranet4 it lets you see immediate changes in CO2 -- and alarms go off when dangerous levels are hit.
Caveat: I haven't had it long enough to know what its (USB-C charging) battery life looks like.
Aranet4 vs. Vitalight Mini
The Vitalight Mini arrives pre-charged in a box with a USB-C cable and an instruction manual. It is a small, thicc, lightweight device with a comically large snap clip attached. Mine was almost fully charged. It has just one button and a lit screen, with air sensor holes on the sides and back (the back are the main sensors).
One long-ish press and the Vitalight turned on with a loud beep that startled me! The Vitalight has a neat feature where when the CO2 goes over 800, aka you’ve hit the danger zone, it beep-beeps an alarm to tell you. The beep can also be turned off by simply clicking the button twice. Two clicks turns it back on.
The Vitalight Mini’s brochure has a handy guide to its color-coded levels: Green (400-800), Yellow (801-1200), Orange (1201-1500), and Red (1501-5000). Here in San Francisco where we’re at sea level the normal reading outside in fresh air on my Aranet4 is always around 450. In my apartment where I live alone and like to keep windows open, I’m used to seeing a reading between 475-500.
I was pleased to see the Vitalight Mini was charged and ready to go when I turned it on. (24 hours later it had gone through 2 of 4 battery bars.) The instructions say to wait 35 seconds for it to calibrate — but even after that I noticed the Vitalight was at 400 while the Aranet was hovering at 460-470. So I followed Vitalight's instructions to do a manual calibration.
This involved button presses to get into a menu then waiting through a countdown of 200 seconds. But nope, it didn’t change: the Vitalight Mini was still showing me 50-60 lower than the Aranet. For most everyone using this for covid risk assessment, the 50-60 range is not a significant margin. But I wanted to see if that margin was consistent over time and over battery life, and if it was consistent at both high and low readings.
I checked the Vitalight Mini versus the Aranet every few hours for the rest of the day, through the night (I don’t sleep at night), and in the morning and afternoon before taking it out. The 50-60 reading being less than the Aranet’s reading remained a consistent difference.
Before taking both sensors out into the wild I wanted to make a safety alteration to my Aranet: I needed to be able to hold both in one hand while I photographed the readings side-by-side. I solved this by adding a finger loop to the back, one of those cheap adhesive finger straps sold for phones.
I made sure to only adhere it to the Aranet’s battery cover and not over any sensors. It now allows me to hold the Aranet4 more securely in one hand, and I highly recommend adding a "phone grip" if you can.
My first stop was Walgreens on Castro Street at 18th. They had the front doors open but no other ventilation I knew about. Most of the employees were masked but only about 1/4 of the customers were.
And it showed on my CO2 monitors. Within two minutes the Vitalight went from 400 to 666, while the Aranet went from 450 to 733. This is not a place anyone should be without a mask while San Francisco is in a six-week-and-counting BA.5 surge.
The Vitalight’s alarm went off at 800 (beeping twice) as its arrow moved from green to yellow. The Vitalight number raced higher and the Aranet refreshed again — now closer to the Vitalight. The Vitalight’s two-beep alarm went off again as its risk category arrow moved to Orange. I was ready to flee but waited for the Aranet to refresh — and then it did, at a higher number than the Vitalight, having overtaken it. The numbers kept going up but I bailed. I had what I needed.
The Aranet’s readings were more precise, but delayed, and there is no alarm to warn me. The Aranet is top of the line and excellent for precision, and its app is not just convenient abut an excellent tool for getting all the data you need, as well as data over time (and keeps a history of readings).
The Vitalight has an acceptable margin of error for an everyday user going to school, the store, taking the bus, going to the dentist, etc. The Vitalight showed me I was in danger much faster than the Aranet4, and that’s a huge advantage, although the accuracy gap seemed to increase as CO2 got worse — but after two alarms you should be getting TF out of there anyway.
The alarms are a huge bonus: if you’re not paying attention, this device will let you know the air is unsafe now. It will be an interesting dynamic when multiple people at a conference (or kids in a classroom) all have alarms go off warning the entire room about toxic air.
Ask me any questions in the comments, or give me suggestions or advice, too! I’m constantly looking for tips and trying to learn how to stay safer, better. Thank you for reading.
Stay apart, stand together, mask up, and stay strong.
xo,
Violet