Review: SPARROW W500

We have discussed a lot of times how air pollution can affect human health in the long-term. However, there is one pollutant that can have a severe impact on our health even in small concentrations in the short-term: Carbon Monoxide (CO).

Carbon Monoxide is a colourless, odourless toxic gas. Carbon monoxide poisoning is the most common type of fatal air poisoning in many countries around the world because it is hard to detect with our senses and it is classified as highly toxic.

About half of the carbon monoxide in Earth’s atmosphere is anthropogenic from the burning of fossil fuels (diesel and gasoline), oil, paraffin, propane, natural gas, trash, and biomass.

Here comes SPARROW W500 Air Quality Monitor by ECO SENSORS, a small portable monitor that can follow you anywhere. It is designed to alert you when high CO concentrations are present.


  • Carbon Monoxide Sensor by SPEC Sensors
  • Humidity Sensor
  • Temperature Sensor
  • Alarm (audible buzzer)
  • Multicolour LED Light
  • Bluetooth Connection
  • Micro-USB port

SPARROW is super small  5.6cm x 3.3cm x 1cm and super light as it weighs 18g/0.03 lbs. You can pair it with a smartphone (iOS and Android) but also it can operate on its own as the buzzer and the Yellow/Red/Purple LED light can notify you when there are significant CO concentrations around. When the CO concentrations are safe the Green LED light will always flash once per second, except when charging, after all it can inform you about the CO concentrations without the need to launch the app or take your phone into your hands.

The battery will last 2 plus weeks, which is great for those who don’t want to charge one more device every day or so. I have set it with a 1 minute data log rate. The device has a button that you need to press every-time you want to connect it with the phone, that way the Bluetooth connection is established at the moment, otherwise the SPARROW would have to be in a mode where it was always broadcasting for Bluetooth signal, which is a huge power drain for both devices, phone and the air quality monitor.

Fortunately, my house is CO free as I don’t burn anything but we all travel and for those with a garage it is a mandatory device to have. In the picture below you can see the device inside a closed jar with smoke from a burning match as I wanted to stimulate the sensor and simulate the CO concentrations. I must say the CO sensor is a lot more stable and cross-sensitivity proof which means other gases won’t affect the measurements.


SPARROW comes with a carabiner clip but there is an option to attach it on the back of a phone case with a special mount system the case maker OtterBox has developed and they support many cases for iOS, Android phone, and tablets.

SPARROW Animation Case

The App

Visually, the app is not pretty but it does the job. There are a lot of options to tweak and to adjust the app and device to your needs but it lacks a better user experience UX though a better user interface UI. Of course, this is something that can be fixed with future app updates.

You can share the measurements (data Log file) via email which is a neat feature but they go a step further and you can connect the device with the micro-USB cable to your computer and enable direct communication, however, this is an advanced feature.

The app allows you to select different data log rates between 1 second / 10 seconds / 1 minute / 10 minutes / 1 hour / 1 day. There is another cool option to enable if you want  the device not to keep low CO concentrations in the log file, that way you don’t have a huge  amount of data entries to process later on, like in my case.

Literally, you can customise the device to your needs even by changing the Sensitivity mode for different thresholds. You can measure in parts per million (ppm) or milligrams per cubic meter (mg/m³). You can set up emergency messaging by allowing SPARROW app to send messages to emergency contacts when very high concentrations are detected.

Premium mobile phone screen mockup template



Breathing CO can cause a series of health issues. Unknowingly, exposure to moderate levels of CO over long periods of time has also been linked with an increased risk of heart disease. If your environment is surrounded by vehicles (suitable for #VanLife) or other sources of burning fossil fuels then having such a device that can guard your health is worth investing in. SPARROW W500 is one of them.

When is the best time to Exercise Outdoors in Athens, Greece?

Well, in winter and early spring never, period! If you are thinking of running or even walking in the center of Athens in Aristotelous street and around then prepare yourself to breathe a lot of pollution.

There is an official air quality station there and I pulled all available data for local statistical analysis from the European server (GR0003A). Unfortunately, 2019 nor 2020 measurements are available to the public yet, maybe in a decade, they will share the data for the Greeks to read. (Τι κάνεις έλληνα και δεν παραπονιέσαι για τον αέρα που αναπνέεις;).

Air Quality Station on top of the building Aristotelous street, Athens
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Series of Innovators: SPEC Sensors


SPEC Sensors was founded in 2012 in the USA (California) by Dr. Joseph Stetter and Ed Stetter. Their gas sensors, analog and digital, are one of a kind as the technology and hard work has allowed them to minimize the sensor size to only 20x20x3 mm in order for gas sensing to become a part of our everyday lives. The company has foreseen that sensors of all types are going to be integrated into smartphones and other wearable devices, becoming an integral part of our everyday lives and building the Internet of Things (IoT).

IoT low-cost sensors are in my DNA as I believe they will allow us to understand environmental issues otherwise, we would have dismissed or we would not be aware.

Let’s read together what they have to share with us and reach a conclusion at the end.


  • Tell us a bit about your motivation in developing air quality sensors?

We saw the need and opportunity for low cost electrochemical sensors with good performance – before SPEC, high performance sensors were too expensive and too big to enable new applications in wearables and distributed monitors. SPEC was born out of the research driven by Eco Sensors / KWJ Engineering, Inc. led by Dr. Joseph Stetter.  We were able to build SPEC Sensors using modern technology in a new high performance plastic package.Read More »

When is the best time to Exercise Outdoors in England?

Based on 2019 data I analyzed the concentration of Nitrogen Dioxide (NO2) and Particulate Matter (PM2.5), when available, as they are two of the most common pollutants in urban environments due to vehicle traffic and household heating.

In a recent study, scientists selected 140,072 adults and after following them for an average of 2 years, they found that physical activity, even in high PM2.5 levels, is an important high blood pressure (hypertension) prevention strategy as the markers remained stable.

This is a great piece of news. However, I prefer to avoid pollution in the first place and not playing the constant game of good and bad. In our lives, many other factors contribute to health issues, and by eliminating air pollution you make sure that the eternal battle of survivor leans towards your favor.

Let’s take some random locations from across England and see which day and time of the week is the best to exercise outdoors. All data are from the official monitoring network (AURN).


I randomly chose to analyze data from the London Marylebone Road (MY1), which is an urban traffic station.

London Marylebone Road (MY1)

Based on the NO2 data, from Tuesday to Friday I don’t recommend anyone to run near that area as the highest concentrations are registered those days especially between 07:00 to 21:00 throughout the year. Remember the annual safe mean according to WHO is set to 40 μg/m3. Weekends and late nights between 00:00 to 06:00 in the morning seem to be adequate to exercise as traffic seems to calm down a lot. January, February, March, and June are the worst months too.Read More »

Review: BRISE Multi-Shield Mask

Another great mask to wear against air pollution and the COVID-19 disease. BRISE the company behind the air purifiers just released the BRISE Multi-Shield Mask and they come in three different colours, Dark Black, Peach Red, and Sky Blue.

BRISE Multi-Shield Masks have some key characteristics that separate them from the competition. A certified filter against PM2.5 pollutants, which can block oily and non-oily pollutants, keep in mind that the most common N95 masks are not resistant to oil). Double water-resistant washable layer that can withstand up to 200 times of hand-washing by maintaining excellent filtration efficiency and long-term effectiveness. Finally, the organic cotton inner layer offers a gentle and comfortable touch to the skin.

The mask offers 3 layers of protection.Read More »

Review: Airthinx IAQ for Homeowners

This review is dedicated to the end-users (homeowners) as I present the tools (Smartphone app) and functionalities of the device for the average user and some basic features on the dashboard. Later on, I will review the same monitor for businesses where we will have the chance to see and analyze the more advanced tools which are present on the dashboard for all.

Airthinx IAQ is an Air Quality Monitor (AQM) that was built for experts with many communication protocols in order to ensure that users will be able to access air quality measurements from anywhere and air quality sensors that matter in the indoor environment.

Technical Specifications

  • PM1 / PM2.5 / PM10 Sensors (0~500 μg/m3)
  • CO2 Sensor (0~3000 ppm)
  • CH2O Sensor (0~1 mg/m3)
  • TVOC Sensor (1-10ppm of EtOH) (0-1ppm of Isobutylene)
  • Temperature Sensor (-10-85°C)
  • Humidity Sensor (25-90 %RH)
  • Barometer Sensor (300-1100 hPa)
  • WiFi (802.11 b/g)
  • Bluetooth 4.0
  • Zigbee
  • GPS
  • Accelorometer 16g (13-bit resolution)
  • 2 Micro-USB Power Ports

Read More »

uHoo – Virus Index (Update)

Some of you have contacted me because you wanted to know my opinion on uHoo’s latest update. Since June 2020, uHoo has implemented a Virus Index which is a patent-pending technology that uses the power of air quality data to help you know how suitable your close environment is for a virus to survive and spread.

uHoo is an air quality monitor that features nine environmental and pollution sensors. If you want to learn more, read my review here.

uhoo app 2020 virus index

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UV Filtration During COVID-19 with BRISE C200 Air Purifier (English/Español)

(Scroll down for the Spanish version/Desplácese hacia abajo para la versión en español)

Two years ago I reviewed the BRISE C200 and I have been using it everyday but I had never thought before that the UV sterilization process will come so handy. It provides an extra layer of protection in a house or in small office especially during this covid-19 pandemic.

I don’t know about your experience during the lockdown, but mine was quite frustrating when I had to go out for grocery shopping and return home or even when I ventilate my house. A lot of things had been written about the SARSCoV2 virus, like that it could survive on clothes, on surfaces (keys, phones, money, etc) and that it can be an airborne pathogen.

Airborne means that a virus is transmitted between people through respiratory droplets and contact routes.Read More »

Why is it so hard to ditch private vehicles from cities?

We all know that cars contribute a lot to air pollution in urban environments, like particulate matter and nitrogen dioxide, among the most common. I see many fellow environmentalists who try to push cities towards a future without cars, but I think with the current means it is very difficult to win the battle.

The automotive industry spends millions on advertising, and they always target the emotional connection that forms between a driver and a car. They will never tell you that cars are important tools that will help you on your work or any other everyday tasks, but they will tell you that a car will offer you freedom as you will be able to escape away from your problems or it will make you a powerful human being and so on.

Take, for example, the first three ads I got as a result when I googled “Car ads”. Powerful subliminal messages to lure you into thinking that a car will make you a new person.

car ads
Just by Googling “Car ads”

When environmental scientists urge communities to leave cars behind they don’t actually do a great job of spreading the message around because they are not trained to do this kind of task. Allow me to elaborate on that. Atmospheric scientists are good at their job which is the study of the Earth’s atmosphere and its various inner-working physical processes. They are able to investigate cases and write papers base on actual facts and among experts, we are able to understand what they want to share but we miss the science of physiology, something that the automotive industry relies on for a century now.

Every day people are not going to read those papers and studies, and if they do, they aren’t going to understand a lot. By giving them the information in a form that they can understand, and without alarming them, we have more chances of making them understand the issue.


When carmakers launch new cars on the market, they are going to involve many more experts on how to make their product more appealing to the costumers, aka everyday people, as a result, we have to fight with the same tools and team up with marketing experts.

Examples of campaigns, we can deploy if we want more people to join the #CarFree movement. Feel free to share them!

Bicycle Power3

Bicycle Power2

Bicycle Power1

Dear city of Almeria (Spain) or any other city in the world (English/Español)

(Scroll down for the Spanish version/Desplácese hacia abajo para la versión en español)

I am writing this article because I would like to help you understand the importance of the issue as the whole province and consequently my city Almeria doesn’t have an official air quality station with a sensor capable of measuring particulate matter with an aerodynamic diameter of 2.5 μm or less (PM2.5) in real-time.

What is Particulate Matter (PM)?

Particulate Matter (PM) are solids material (sometimes liquid too) that float in the air. Some PM is released directly from a specific source − combustion in Diesel engines − while others form in complicated chemical reactions in the atmosphere.

Particles in the PM2.5 size range can travel deeply into the respiratory tract, reaching the lungs. Studies also suggest that long term exposure to fine particulate matter may be associated with increased rates of chronic bronchitis, reduced lung function and increased mortality from lung cancer, and heart disease. People with breathing and heart problems, children and the elderly may be particularly sensitive to PM2.5.

The Problem

In the province and city of Almeria, there are three Air Quality Stations that measure many pollutants one of which is PM2.5. Unfortunately, these sensors are outdated and the results we get are ONE daily average value which is basically useless in my opinion. Apart from that, we need to wait for a month to get the results back after filing a form. I guess the same thing applies to the 68 stations all around Andalucia in total.

Citizens need real-time data in order to take action and reduce their exposure to air pollution. They also need better tools and maps where they can visualise where pollution is in order to avoid harmful exposure. There are already many studies supporting the correlation between air pollution and COVID-19 cases.Read More »