Air Quality Monitoring and Alerting System to Help in Reducing

Asthma Attack in Asthmatic Children

Khawla Alzoubi

1,2

, Manal Al-bzoor

, Omar Aljalahma

and Mohamed Ali

Qatar University, Doha, Qatar

Community College of Qatar, Doha, Qatar

Yarmouk University, Irbid, Jordan

Keywords: Asthma Attack, Air-quality, Alerting Subsystem, Bluetooth, Environmental Factors, Monitoring Subsystem.

Abstract: Asthma attack is one of the most common emergency cases seen in hospitals. It can be dramatically triggered

by environmental factors such as air pollution, temperature and humidity. In this paper, we developed a system

to avoid asthma attacks, especially for children, by informing parents about the air quality conditions. Our

developed prototype system consists of two main subsystems that communicate wirelessly. The first

subsystem is an Air-Quality Sensing Subsystem, and the second subsystem is a mobile phone application.

The Air-Quality Sensing Subsystem (AQSS) collects data from surrounding environment about the air-quality

using different sensors that measure the main environmental factors (temperature, humidity, dust, and Carbon

Monoxide (CO)) that trigger asthma attack in our region (Qatar). This subsystem processes the collected data

and decides whether the air-quality is safe for asthmatic children. The processed data along with alerting

messages are sent to the smart-phone app wirelessly using Bluetooth technology. The Smart-phone app shows

the measured air-quality factors as well as sends a message to inform the parents if the air-quality outside is

safe for their asthmatic children or not. Accordingly, parents can take precautions to protect their asthmatic

children from having asthma attack. This would help in stabilizing the health condition of asthmatic

children/person and avoid costly hospitalization procedures.

1 INTRODUCTION

Asthma is a chronic disease in respiratory system

associated with the airway. Asthma is a Greek word

that refers to the difficulty of breathing. The triggers

of this disease are different in adults, children’s, and

vary in relations to gender. (Guarnieri et al, 2015).

The real causes of asthma are not fully understood.

The causes are combined of both genetic and non-

genetic factors. The causes include chronic obstructive

pulmonary, bronchitis, chronic sinusitis, respiratory

infections and heart disease. According to the Global

Asthma Report 2018, asthma is estimated to affect as

many as 339 million people around the world.

However, deaths of asthma were estimated to be 1000

people per day, most commonly in poor countries.

Asthma attack leads to tightening the muscles

around the airways, causing some dangerous

symptoms to the patient. The known symptoms of

asthma attack are wheezing, dyspnoea, chest

tightness, cough, weak exercising, changes in lung

function, and trouble sleeping (Holgate, 2010). Many

factors affect asthmatic people, and can trigger their

asthma if these factors exceed specific values and

limits. These factors can result from weather

conditions (Humidity, heat, dust, cold), air pollution

(chemical gases), and other sources (pet dander,

pollen and mold, food, and drugs).

Managing asthma is the best way to avoid asthma

attack and its consequences. Asthma has no cure;

hence, the only way to reduce its effects is by following

these steps in sequence: First, controlling asthma with

medications and using the flow meter to prevent the

symptoms by allowing Oxygen to enter the airways

and help maintain good lung function. Second,

working with doctors to treat other diseases that can

trigger asthma attack. Third, avoiding factors that

could trigger asthma attack (Haughney et. al, 2020).

Environmental factors may result from weather

conditions and air-pollution. Air could be poluted by

Ozone (O3), Sulphuric Dioxide (SO2), Carbon

Monoxide (CO), oxides of nitrogen (NO, NO2), and

Carbon Dioxide (CO2) (Diette et. al, 2008). Ozone

gas has a serious effect on asthmatic people. In Qatar

Alzoubi, K., Al-bzoor, M., Aljalahma, O. and Ali, M.

Air Quality Monitoring and Alerting System to Help in Reducing Asthma Attack in Asthmatic Children.

DOI: 10.5220/0009971200910098

In Proceedings of the 14th International Joint Conference on Biomedical Engineering Systems and Technologies (BIOSTEC 2021) - Volume 1: BIODEVICES, pages 91-98

ISBN: 978-989-758-490-9

specifically, air-pollution with greenhouse gases and

toxic gases emissions generated by vehicles and

factories may have a serious impact on asthmatic

patients. Furthermore, dust and sand in this region

create serious health problems to people with asthma

and respiratory system related diseases. Moreover,

the high levels of temperature and humidity can also

trigger asthma attack as humidity and heat pose a

particular risk as a breeding ground for mold spores,

which contribute to asthma attack (Haughney et. al,

2020).

Asthmatic children, in Qatar, are at a higher risk

from exposure to the aforementioned environmental

factors that trigger asthma attack due to their

immature lung development and their weak and

sensitive bodies. Therefore, this project aims to

develop an air-quality monitoring and alerting system

to monitor the most environmental factors that would

trigger asthma attack in asthmatic children in Qatar

and other regions that have similar circumstances.

This project will equip parents with a mechanism to

check the outdoor air-quality in a specific region and

alert them if any of the environmental factors exceed

the safe standards. These safe standards are decided

based on the reported values and ranges of dangerous

level of the enviromental parameters in previous

studies. These levels will be presented in this work.

Recently, monitoring Air-quality has been

explored by many researchers in the aim to measure

the air-quality in-doors and out-doors for health and

safety issues. A research group in Qatar was designed

and implemented a system to measure the indoor and

outdoor air quality (Alassi et al. , 2016). In their work,

they developed a system to measure and monitor the

environmental harmless gases such as Carbon dioxide

(CO2), nitrous oxide (N2O), and methane (CH4). In

addition, they focused on the nature parameters such

as dust, temperature and humidity. The data was

collected by a sensor node, which communicates

wirelessly using IEEE 802.15.4 protocol with a host

computer that receives the collected measurements,

processes them, and shows them using the LabVIEW

software (Alassi et al. , 2016). In their work, they only

monitored the air-quality without providing a

mechanism for alerts on the air-quality. Their system

was general system that monitors air-quality without

considering asthmatic patients and children.

Another research group (Lal and Kulkarni, 2016)

developed a prototype for a system to monitor air-

quality to measure factors that might trigger asthma

attack. Their system consists of PIC microcontroller

and different sensors such as temperature, humidity

and gas sensor that sense Carbon Monoxide,

Hydrogen, Oxygen and alcohol vapor. The developed

prototype system was capable of showing the

measured gases on an LCD as well as sending these

measurements wirelessly using ZigBee to a database

for further analysis. Their system was capable of

measuring just two quanties, the ozone level and the

dust particles.

Plume Air application (Betts, 2020b) was made

for the people who want to adjust their outdoor

activity according to air quality. The application has

a simple GUI that is easy to use which ensures the

user can do outdoor activates such as exercising. The

screen shows the state of the air quality index.

Furthermore, the application can use statistical data to

inform the user of the best day to go out within a

week. Plume also offers a social image tool, periodic

alerts, and map comparing the air quality in different

areas. This application cannot be used in all regions

as it just provides information about the air-quality in

specific areas. This mobile app and other similar

mobile apps give general information about the air-

quality without considering asthmatic patients and

asthmatic children (AIR MENTOR, 2019).

To address the shortcoming in the previous

reported works, this paper presents the development

of a portable wireless air-quality sensing unit, and a

mobile application to display the air-quality data and

inform the parents of any environmental risk that

would trigger asthma attack for their asthmatic

children.

The rest of this paper is organized into four

sections. Section two discusses the system design.

Section three presents the process of selecting the

usensors and components,and implementing the

system. Section four discusses the whole system

testing and packing. Finaly, section four concludes our

works and discusses the future extension for this work.

2 SYSTEM ANALYSIS AND

DESIGN METHODOLOGY

To develop the proposed solution, a portable air-

quality sensing unit, and a mobile application should

be designed and implemented. As our system should

be portable, thus parents can carry it anywhere and

check the air-quality outdoor before letting their

children to go to that region or area. The system

should be equipped with the sensors that can measure

the riskier environmental factors that would trigger

asthma attack in asthmatic children.

Based on our analysis and studies of the most

environmental factors that would trigger asthma

BIODEVICES 2021 - 14th International Conference on Biomedical Electronics and Devices

attack in our region, we have decided to equip the air-

quality sensing unit with the following sensors:

1) Temperature sensor to measure the temperature as

the high level of temperature in Qatar is one of the

main factors that triggers asthma attack in

children.

2) Humidity sensor to measure the level of humidity

as the high level of humidity affects the asthmatic

children. And high level of temperature leads to

increase the humidity level.

3) Carbon Monoxide(CO) sensor to measure CO gas

as it is one of the most common gases that affect

asthmatic children in Qatar.

4) Dust sensor to measure the size of the dust. As

Qatar is located in desert region its location made

the country exposed to frequent dust storms that

are full of dust particles which highly trigger the

asthma attack in asthmatic children.

The design of whole system is shown in Figure1.

The Air-Quality Sensing unit consists of the sensors,

Microcontroller unit, power management unit,

Wireless Bluetooth module. Sensors measure the

physical environmental factors from surrounding and

convert them to readable measurements that can be

handled by Microcontroller unit (MCU). The MCU

reads, collects, and manipulates the sensors

measurements to make decision about the air quality

condition. A Power Management Unit(PMU) is used

for charging/discharging the battery that power the

system.

The mobile app is a user friendly app shows the

parents the air-quality of the surrounding, and alarms

them if any of the environmental factors that trigger

asthma exceeds its safety level for asthmatic children.

As everybody has a smart mobile these days, parents

can install this app in their smart-phone and connect

it with Air-quality Sensing unit. To enable parents to

use our system as standalone system, in case if they

do not like to see details information, the air-quality

Sensing unit will be equipped with a RED LED and

GREEN LED. If any of the environmental factors

exceeds its safety level, only the RED LED will turn

The Bluetooth module is used to send wirelessly the

manipulated sensors measurements and decision

about the air-quality to the mobile app.

A Bluetooth Low Energy (BLE) module to save

power.

ON, and if the Air-quality is safe for asthmatic

children the GREEN LED only will turn ON.

Figure 1: System Design. Block Diagram.

The ranges of asthma triggering parameters are

not determined yet in literature. We have searched the

literature and different resources about the ranges of

environmental factors according international health

organizations (‘High and low humidity not good for

asthma - Minimizing Triggers – Asthma, 2019). The

collected data about the safe ranges (low, medium,

high) and danger ranges are summarized in Table 1.

Table 1: Range of Environmental Parameters.

Parameter Low level (safe) Medium level High level

Dangerous level

(alert)

Unit

Temperature (Vann,

Madeline R., et al, 2012)

30 - 34

35 -39

29 - 20

40 – 48

19 - 10

>48 or < 10 Celsius

Humidity (| (Bottrell,

2009)

30 – 40

41 – 49

29– 20

50 – 60

19 – 15

> 60 or < 15 %

Dust (Airveda team,

2017)

PM 1: 0-5

PM 2.5: 0-30

PM 10: 0-50

PM 1: 6-10

PM 2.5: 31-60

PM 10: 51-100

PM 1: 11-21

PM 2.5: 61-90

PM 10: 101-250

PM 1: >21

PM2.5: >91

PM10: >251

µg/m

CO (Kidde, 2018) 0 – 50 51 – 100 100 – 400 > 400 PPM

(E Instruments,

2018)

0 – 0.1 0.2 – 5 6 – 10 >10 PPM

NO (E Instruments, 2018) 0 – 50 51 – 150 151 – 200 201 – 700 PPM

(CATA, 2018) 0 – 0.075 0.076 – 0.095 0.096 – 0.374 More than 0.374 PPM

Air Quality Monitoring and Alerting System to Help in Reducing Asthma Attack in Asthmatic Children

The ranges in this table are used as the reference

in this work. Thus, our system can decide and inform

the parents if the air quality outside is safe or not for

their asthmatic children. As all the available collected

information about the safety of these factors for

normal person, we would consider in our work that

even late medium and high level as a dangerous level

for asthmatic children as their lung system is more

sensitive and their bodies are weak.

3 SYSTEM IMPLEMENTATIONS

To implement the Air Quality Monitoring and

Alerting System, each subsystem has to be

implemented separately. We started our work by

implementing the Air-Quality Sensing Subsystem,

and then we implemented the Mobile Application

Subsystem. In the following subsections, the

implementation of each subsystem is demonstrated.

3.1 Air-quality Sensing Subsystem

To implement this subsystem, sensors’ modules,

MCU, BLE module, and PMU were selected

carefully considering the system requirements and

constraints. The Mbed LPC1768 MCU is used as it

has many peripherals which enable it to be capable of

reading analogue and digital data, communicate

serially with different modules using serial

communication protocols such as UART, SPI, I2C,

PWM and other peripherals’ circuitry. Furthermore it

is a 32-bit MCU running at 96 MHz and has 512 KB

flash memory and 32KB RAM. In this project, for

prototyping, we used the Mbed development board.

Each sensor module that measure the most

environmental factors (Dust, Carbon Monoxide

Sensor, Temperature and Humidity Sensor) is

selected, studied, and interfaced separately with

Mbed MCU.

Dust Sensor. The selected dust sensor module is

PMS5003. This sensor module can detect the small

particles, which hurt the respiratory system for the

asthmatic children. It can be easily interfaced with a

MCU using UART serial communication protocol

(Yong and Haoxin, 2016).

The circuit connection needs two 10kΩ pull-up

resistors. The resistors are used to control the set

level. High level or suspending is normal working

status, while low level is sleeping mode. The sensor

results should appear after 30 second from the wake-

up state and the fan performance. The sensor

measurements ranges are from (0.3~1.0；1.0~2.5；

2.5~10) with a unit of micrometer (μm/m3). The

output is the number of each particles with different

sizes per unit volume. For this sensor, the default

mode is active the power. In this mode, the sensor

starts to send the data to the microcontroller. For the

active mode, it is grouped into two sub-modes, stable

and fast mode. The sub-mode depends on the change

of the concertation as if it is small it will be stable and

if it is big it will be fast mode. The higher the

concentration, the shorter the interval. The required

code was written for Mbed MCU to read the sensor

data and test the measurement. The results of testing

the dust sensor shown in Figure 2(a).

Humidity Sensor. The Grove humidity sensor

SEN51035P is used in implementing Air-Quality

Sensing Subsystem. This sensor can measure both

humidity and temperature. It measures humidity in

the percentage range of 20-90% RH, and temperature

in the range of 0-50C degree Celsius. This sensor

provides digital measurements as it has ADC circuity

inside that converts the analogue measurement to

digital data that can be read immediately on a GIOP

pin of MCU. It measures and provides humidity and

temperature values serially over a single wire. This

sensor module is interfaced with Mbed

Microcontroller immediately as it needs just 5V

voltage source and a pull-up resistor that should be

connected with its digital output pin. In Mbed MCU

as its ports are internally connected with pull-up

resistor, this sensor was connected directly without

using external pull-up resistor to streaming the

measurements. The required code was written for

Mbed MCU to read the sensor data and test the

measurements. The results of testing this sensor is

shown in Figure 2(b).

Carbon Monoxide Sensor. The MQ-7 CO sensor

module is used to check if the air is polluted with

Carbon Monoxide or not. This sensor is interfaced

directly with Mbed Microcontroller by connecting the

DO (Digital out pin) to one GIOP port of the Mbed

Microcontroller, and connecting the AO (Analog out

pin) with Analog input port of the Mbed MCU. Two

LEDs are used in this sensor module: Power/

calibration LED and danger LED. When this sensor

is powered and in calibration mode, the first LED

turns ON. During the calibration mode, the user can

adjust the sensitivity of CO sensor using the variable

resistor. In this work, the sensitivity of Carbon

Monoxide sensor was adjusted to exceed the danger

level that would trigger Asthma attack for Children.

When the sensor starts to measure the CO

concentration, and it reaches the adjusted level, the

second LED will turn to indicate that CO

BIODEVICES 2021 - 14th International Conference on Biomedical Electronics and Devices

concentration is in the danger level. The sensor can

measure between 20-2000ppm. Thus, this sensor can

detect the danger level that set according to Table1.

The CO sensor was interfaced to the Mbed MCU as

shown in Figure 3. A program for Mbed MCU was

written for calibrating the sensor and streaming its

data. The results of testing this sensor are shown in

Figure 2(c).

(a)

(b)

(c)

Figure 2: Measurements and Testing of a) Dust sensor

PMS5003 b) Grove humidity sensor SEN51035P c) MQ-7

CO Sensor.

Figure 3: Illustrative block diagram for the Air-Quality

Sensor Subsystem.

To enable the Air-Quality Sensing subsystem

(AQSS) to send data wirelessly to the mobile App, a

BLE module is used. The used BLE in this subsystem

is Bluefruit BLE module. This Bluefruit LE is a low

energy and has small footprint size. It can be

interfaced with Mbed MCU using UART serial

communication protocol. The hardware interfacing

between the BLE module and Mbed MCU is

demonstrated in Figure 3. A program for Mbed MCU

was written to test the functionality of the BLE

module.

After interfacing and successfully testing the

functionality of each sensor module and the BLE

module separately, all the modules were interfaced

with Mbed microcontroller as shown in the

illustrative block diagram of Figure 3.

The software part (program) of the AQSS is

developed for Mbed MCU to initialize, calibrate (if

needed), acquire raw data of the sensors, manipulate

data and measurements, make decision, and send

processed data and alarming messages wirelessly

using Bluetooth module to a host computer for

testing. The flowchart for the software part for AQSS

is shown in Figure 4. The program was written using

C++ language in Mbed online development

environment. Thus, this program enables the AQSS

to perform tasks from acquiring sensors’

measurements until sending processed data and

alerting message over the BLE module to the other

subsystem (Mobile App).

3.2 Mobile App Subsystem

To inform parents of asthmatic children about the air-

quality in friendly manner, we designed and

implemented a mobile application that can

communicate with the AQSS using the BLE

technology. App Inventor program for Android was

used to design the application which is an open source

web application provided by Google. The designed

application consists of Graphical User Interface

(GUI) that the user can see, and programming blocks,

which are hidden from the user. The designed GUI

for the App is shown in Figure 5. The background of

the screen was designed to represent the outdoor

environment. To start the application, the user must

click on the scan button that will search for available

BLE devices. The user has to choose the AQSS to

connect with and receive messages from it. After

clicking on Adafruit Bluefruit LE, which is the device

used for this project, the application screen will show

the address of the connected device and a green tick,

indicating the connection is done. A disconnect

option could be used to disconnect the device. Figure

6 shows the GUI of the Mobile App after connecting

with AQSS.

Air Quality Monitoring and Alerting System to Help in Reducing Asthma Attack in Asthmatic Children

Figure 4: Flowchart for Air-quality Sensing Subsystem

(AQSS).

Figure 5: Start GUI of the mobile App.

Figure 6: GUI of App after connecting with AQSS.

4 SYSTEM INTEGRATION AND

DISCUSSION

For the final presentation, a PCB board was printed,

and all the components of The Air-Quality sensing

subsystem were assembled on it. The PCB for the

sensor’s subsystem was designed using DipTrace

Software. The PCB design is shown in Figure7. In the

designed PCB board, the circuit wiring connections

for PMU were added, and the circuit wiring

connections for two status LEDs (RED and GREEN)

were added. Furthermore, to control turning the Air-

Quality Subsystem ON/OFF, the required wiring

connections were added.

Figure 7: PCB design for the Air-Quality Sensor

Subsystem.

As the AQSS should be portable, the PMU was

interfaced with Mbed MCU and all other modules and

components to manage power the whole AQSS using

rechargeable battery as well as charging the battery.

BIODEVICES 2021 - 14th International Conference on Biomedical Electronics and Devices

The battery-life for (AQSS) was also calculated for

different scenarios. It was found that the battery-life

(68000 mAh) is 12 hours if this system works

continuously. To prolong the battery-life of this

system, a switch was added to turn it ON/OFF. Thus,

the system can run for longer time before it needs to

be recharged. Moreover, to make this system capable

of informing the parent if the air-quality is safe or not

for their asthmatic children with using mobile app,

alert status LEDs were added which will turn green

LED on when the air quality is in good level and turn

red LED on when the air quality is dangerous for

asthmatic children. Furthermore, a 3-D box was also

printed using 3D printer to host nicely this AQSS.

Figure 8: Final assembled prototype for AQSS.

Figure 9: Final packing for the prototype of AQSS.

The final prototype for AQSS was assembled on

the produced PCB board and hosted in the 3D

package as shown in Figure 8 and Figure 9

respectively. The developed app works on android

devices (Mobile phone or tablet). The Air-Quality

Sensing Subsystem and the Mobile App subsystem

were tested together. After turning ON the Air-

Quality Sensing Subsystem, the Mobile App was

opened and connected to AQSS. The sensors’

measurements are shown on the Mobile App as

demonstrated in Figure 6. The final prototype (shown

in Figure 9) was tested with the Mobile application in

different environment settings (dust, heat, and

humidity). To test the whole system in measuring the

CO, the flame of lighter is used in proximity to the

CO sensor of the AQSS. The developed prototype for

the Air Quality monitoring and alerting system works

successfully and shows real time measurements (on

the mobile app) that are received from the Air-quality

sensing subsystem over the BLE. For CO sensor

module, it shows a warning when the concentration

of the CO exceeded the set point. As it was mentioned

previously, the set point can be changed by varying

the variable resistor on the CO sensor. For our system,

the set point was set to the dangerous level for

asthmatic children (150ppm). In Figure 6, there was

no warning message as the system was tested indoor

in a normal environment setting.

5 CONCLUSIONS

The developed prototype system, in this work, can

collect data about environmental factors that trigger

asthma attacks in our region (Qatar). It shows the

collected measurements on mobile app and alert the

user when the out-door air quality degrades to a level

that trigger asthma attacks especially in children who

are more sensitive to asthma trigger factors.

Therefore, the developed system will help in

managing and avoiding asthma attacks for asthmatic

children by informing their parents in a real-time

manner. Thus, the life-quality for asthmatic children

will be improved as well as avoiding un-necessary

costly hospitalization. The developed system is

portable and user friendly. Thus, parents can use it

anywhere to check the surrounding air-quality and

avoid exposure of their asthmatic children to polluted

and unhealthy out-door environment. This work will

be extended by providing each sensing subsystem

with GPS and GSM modules to form IOT

infrastructure. Thus, the sensor subsystem can send

the collected data to the cloud database. The cloud

services can be used to analyze the environmental

sensor measurements data. The Air Quality Sensing

Subsystems(AQSSs) can be distributed in different

locations. All the AQSSs can send their data to the

cloud by utilizing the available IOT infrastructure.

Therefore, parents of asthmatic children can access

the cloud webserver and get updated information

about the air-quality level in a specific location at a

specific time.

Air Quality Monitoring and Alerting System to Help in Reducing Asthma Attack in Asthmatic Children

ACKNOWLEDGEMENTS

This work was supported in part by the Qatar

University Student Grant under Grant number

QUST‐1‐CENG‐2019‐12.

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BIODEVICES 2021 - 14th International Conference on Biomedical Electronics and Devices