Lecture 60: Sampling and Analysis of PM10 & PM2.5 using Spectrometer

Summary

This video script details the use of spectrometer-based instruments for sampling and analyzing particulate matter, specifically PM10 and PM2.5. It covers the importance of particulate matter in air quality and health, the principles of light scattering for particle measurement, and the operation of the GRIMM spectrometer. The script also explains the process of data collection, software analysis, and the comparison between high-volume samplers and spectrometers, concluding with a lab demonstration and acknowledgments.

Takeaways

• 🔬 The script discusses the use of a spectrometer for sampling and analyzing particulate matter (PM10, PM2.5, and even PM1), offering an alternative to the gravimetric methodology using high-volume samplers.
• 📚 The lecture provides an overview of the importance of particulate matter in terms of environmental and health impacts, highlighting the significance of fine and ultra-fine particles.
• 🌟 National Ambient Air Quality Standards for PM10 and PM2.5 are mentioned, with specific concentration values not to be exceeded for annual and 24-hour periods.
• 🛠 The GRIMM instrument is introduced as the spectrometer-based tool used for monitoring particulate matter, with a detailed description of its components and setup.
• 💡 The principle of light scattering by single particles is explained as the basic working mechanism of the spectrometer, which allows for the measurement of particle count and mass concentration.
• 📉 The process of preparing the spectrometer for data collection, including the careful handling of filter paper and ensuring its accurate weighing, is outlined.
• 🖥️ Data analysis is facilitated by software provided with the spectrometer, which allows for the selection of time intervals, data transfer to a PC, and the creation of spreadsheets for easy analysis.
• ⏱️ The importance of synchronizing the spectrometer's time with the PC time to avoid errors in time recording is emphasized, with a recommendation for regular synchronization.
• 🔍 The script includes a demonstration of how to use the spectrometer's control software for real-time monitoring and data collection, including setting up user settings and starting/stopping the device.
• 📚 A lab-based video is mentioned, which illustrates the sampling and analysis process of PM10 and PM2.5 using a spectrometer, providing a visual aid to the lecture's content.
• 📈 The versatility of the spectrometer is highlighted, as it can measure not only mass concentration but also particle count, which is crucial for source identification and compliance with air quality standards.

Q & A

What is the primary topic of the lecture?

The primary topic of the lecture is the sampling and analysis of particulate matter, specifically PM10 and PM2.5, using spectrometer-based instruments.

What are the two main methods discussed for sampling PM10 and PM2.5?

The two main methods discussed for sampling PM10 and PM2.5 are the gravimetric methodology using a high-volume sampler and the spectrometer-based method.

Why are particulate matters important to monitor?

Particulate matters are important to monitor due to their significant impact on both the environment and human health, as they can cause various respiratory issues.

What are the National Ambient Air Quality Standards for PM10 and PM2.5?

The National Ambient Air Quality Standards for PM10 and PM2.5 are an annual concentration of 60 and a 24-hour concentration of 100 for both, which should not be exceeded.

What is the role of the spectrometer in measuring particulate matter?

The spectrometer measures particulate matter by using light scattering principles. It can provide not only mass concentration but also the count of particles.

What is the basic principle behind the spectrometer's operation?

The basic principle behind the spectrometer's operation is the light scattering by single particles, which is then detected by a detector, allowing for the monitoring of particle count and mass concentration.

What is the significance of the filter paper in the spectrometer?

The filter paper is crucial in the spectrometer as it is used to collect particles for analysis. It must be carefully handled, weighed, and replaced to ensure accurate measurements.

How is data transferred from the spectrometer to a desktop or laptop?

Data is transferred from the spectrometer to a desktop or laptop using a software provided by the spectrometer manufacturer, which allows for the selection of ports, setting time intervals, and initiating the monitoring process.

What is the importance of synchronizing the device time with the PC time?

Synchronizing the device time with the PC time is important to avoid errors in time recording, ensuring that the data collected is accurately timestamped.

How can the data collected by the spectrometer be analyzed?

The data collected by the spectrometer can be analyzed using the provided software, which offers various options for data visualization, including graphs, tables, and statistical analysis.

What is the purpose of the video presented in the lecture?

The purpose of the video is to illustrate the sampling and analysis process of particulate matter, specifically PM10 and PM2.5, using a spectrometer in a laboratory setting.

Outlines

00:00

🌍 Introduction to Particulate Matter Analysis with Spectrometer

The script begins with an introduction to the analysis of particulate matter, specifically PM10 and PM2.5, using spectrometer-based instruments as an alternative to the high-volume sampler. It outlines the lecture's structure, which includes an introduction to particulate matter, its importance, national air quality standards, the working principle of a spectrometer, the equipment used, and the process of data analysis. The script emphasizes the health and environmental impacts of particulate matter and mentions the capability of spectrometers to measure even finer particles like PM1.

05:02

🔬 Components and Setup of the Spectrometer for Particulate Matter Measurement

This paragraph delves into the components of the GRIMM spectrometer used for monitoring particulate matter. It describes the setup process, including the placement of the instrument in the field housing, the dust monitor, the filter paper, and the data storage device. The spectrometer's front panel features an LCD screen and a keypad, while the back panel houses the filter paper slot and cable outlets. The paragraph also explains the basic principle of operation, which involves light scattering by particles detected by a spectrometer's detector.

10:05

📝 Procedure for Filter Paper Handling and Data Analysis

The script explains the meticulous procedure for handling the filter paper, emphasizing the importance of careful placement and weighing to ensure accuracy in particulate matter measurement. It continues with a description of how data is transferred to a desktop or laptop, the software used for data analysis, and the customization options available for monitoring intervals. The paragraph also discusses the importance of synchronizing device time with PC time to avoid errors in time recording.

15:06

🖥️ Software Interface and Real-Time Monitoring of Particulate Matter

This section introduces the software interface provided by GRIMM for controlling and monitoring the spectrometer. It outlines the steps for configuring the spectrometer, including selecting communication ports, setting time intervals, and syncing device time with the PC. The script also describes the user settings for defining output files and initiating the measurement process. It provides an overview of the different tabs and options available in the software for real-time monitoring and data analysis.

20:09

📈 Data Visualization and Statistical Analysis Using the Spectrometer Software

The paragraph discusses the various ways in which the spectrometer software presents data, including distribution tables, live readings, graphical presentations, and statistical analysis. It explains how to interpret the data in terms of particle counts per liter and mass concentration in micrograms per cubic meter. The script also covers how to save graphics and convert data into a spreadsheet format for further analysis, which is essential for understanding the variation of particulate matter over time.

25:14

📚 Conclusion and Acknowledgments for the Particulate Matter Monitoring Course

In the concluding paragraph, the script summarizes the course on particulate matter monitoring using a spectrometer and acknowledges the contributions of various individuals involved in the course. It highlights the versatility of the spectrometer in providing both count and mass concentration of particulate matter and emphasizes the importance of such data for source identification and compliance with air quality standards. The script ends with a thank you note to the participants and a wish for their future endeavors in air pollution control and studies.

Keywords

💡Particulate Matter (PM)

Particulate Matter (PM) refers to a mixture of solid particles and liquid droplets found in the air. In the video, PM10 and PM2.5 are specifically discussed, which are particles with diameters less than 10 and 2.5 micrometers, respectively. These particles can penetrate deep into the respiratory system and are associated with a range of health and environmental issues, making them a central theme of the video.

💡Spectrometer

A spectrometer is an instrument used to measure properties of light over a specific portion of the electromagnetic spectrum. In the context of the video, a spectrometer is used to analyze PM10 and PM2.5 by measuring light scattering from airborne particles. The script mentions the use of a spectrometer-based instrument to monitor particulate matter, emphasizing its role in air quality assessment.

💡National Ambient Air Quality Standards (NAAQS)

NAAQS are standards set by regulatory bodies to protect public health and the environment from the harmful effects of air pollutants. The script discusses these standards for PM10 and PM2.5, highlighting the annual and 24-hour concentration limits that should not be exceeded to maintain air quality.

💡Light Scattering

Light scattering is a phenomenon where light is deflected or dispersed as it passes through a medium. In the script, the principle of the spectrometer is based on light scattering by single particles, which is detected and used to determine the count and mass concentration of particulate matter.

💡GRIMM Instrument

The GRIMM instrument, as mentioned in the video, is a specific type of spectrometer used for monitoring particulate matter. It includes components like an EDM (Environmental Dust Monitor) and a memory card for data storage. The script describes its various parts and functions, illustrating its importance in the sampling and analysis process.

💡Data Storage

Data storage in the context of the video refers to the method by which the spectrometer records and saves the measurements taken during the monitoring of particulate matter. The script mentions the use of a memory card in the GRIMM instrument for storing data, which can later be transferred to a desktop or laptop for analysis.

💡Software Analysis

Software analysis is the process of using computer programs to interpret and understand data. The video script describes the use of specific software to analyze data collected by the spectrometer. This includes setting time intervals for data collection, selecting ports, and converting data into spreadsheets for further examination.

💡Optical Particle Counter

An optical particle counter is a device that counts and sizes particles in a gas using a light scattering principle. The script explains that the GRIMM spectrometer can function as an optical particle counter, providing data on particle counts per liter, which is crucial for understanding particulate matter distribution.

💡Filter Paper

Filter paper is used in the context of the video for gravimetric analysis, where the filter is weighed before and after sampling to determine the mass of collected particles. The script emphasizes the careful placement and weighing of filter paper to ensure accurate measurements of PM2.5.

💡Real-Time Monitoring

Real-time monitoring refers to the immediate recording and analysis of data as it is collected. The video script describes the use of GRIMM software for real-time monitoring of PM10, PM2.5, and PM1 levels, allowing for the observation of air quality changes and immediate response if necessary.

💡Air Pollution Control

Air pollution control encompasses the policies, regulations, and technologies aimed at reducing the emission of pollutants into the atmosphere. The script concludes by emphasizing the importance of monitoring particulate matter for air pollution control and the application of the knowledge gained in the course to this field.

Highlights

Introduction to spectrometer-based sampling and analysis of particulate matter (PM10, PM2.5, and PM1).

Importance of particulate matter for environmental and health impacts, including respiratory issues.

National Ambient Air Quality Standards for PM10 and PM2.5, including annual and 24-hour concentration limits.

Principle of light scattering by single particles in spectrometer for measuring mass concentration and particle count.

Components of the GRIMM spectrometer instrument, including EDM, field housing, dust monitor, and memory card for data storage.

Setup and operation of the spectrometer, including placing the filter paper and ensuring proper weight measurement.

Data transfer to desktop or laptop for analysis, with software options for selecting ports, setting time intervals, and monitoring.

Synchronization of device time with PC time to avoid errors in time recording of data.

User settings for defining output files, adding comments, and selecting location for data analysis.

Real-time monitoring and data collection with the ability to set time intervals from 6 seconds to 1 hour.

Analysis of data using software, including options for counts per litre, microgram per cubic metre, and mass concentration.

Comparison between high-volume sampler and spectrometer in terms of functionality and robustness.

Lab-based video demonstration of PM10 and PM2.5 sampling and analysis using a spectrometer.

Use of GRIMM model spectrometer for measuring PM10, PM2.5, and PM1, with software provided for monitoring and data analysis.

Procedure for saving and extracting data from the spectrometer, including converting data into spreadsheet format for further analysis.

Application of spectrometer data for source identification, relating concentrations, and comparing with air quality standards.

Acknowledgements and closing remarks, thanking participants and expressing well wishes for future air pollution control and study pursuits.

Transcripts

Sampling and Analysing of Particulate  Matter (PM10 & PM2.5) using Spectrometer  

Hello friends, you may recall we discussed  about gravimetric methodology to do the  

sampling or monitoring of like PM10 and  PM2.5 using the high-volume sampler,  

we can also do sampling and analysis  of particulate matter especially  

PM10, PM2.5 even less than PM2.5 like PM1 using  spectrometer-based instruments basically. So,  

this methodology today we will discuss and this is  the last lecture of this particular course.  

So, first of all, we will discuss briefly  about the introduction, why particulate  

matter are so important, the National Ambient  Air Quality Standards for PM10 and PM2.5,  

what is the principle of the method of a  spectrometer and which kind of equipments are  

used and how measurements are carried out. Then,  the software which is used for this purpose, so  

how it is used and how does it help in  analysis of the data, then the lab-based  

video we will screen and we will conclude. So, as this primary air pollutant particulate  

matter is very important because of its effect  on the environment as well as on the health and  

these fine particles they can go to the  respiratory system and they can cause several  

kinds of health issues basically. So, ultra-fine  particles are also very important like PM1  

and less and they can also be measured but in  this presentation we will discuss about only  

PM10 and PM2.5. But using the spectrometer  I repeat that even PM1 and less than PM1  

can be measured basically. So, this PM10 and PM2.5 air quality standards,  

National Ambient Air Quality Standards are  there like annual 24 hours. So, for those  

like industrial residential areas or  ecologically sensitive areas values are same,  

like annual concentration of PM10 is 60 in  both cases, 24 hours concentration is 100 in  

both cases. Similarly, for PM2.5 annual  concentration is 40. So, this should not  

exceed if we go on getting exposed throughout  year and 60 is the 24-hour maximum concentration  

it should not violate or it should not exceed  at a particular location for PM2.5.  

If we talk about the spectrometer based  instrument, so basically we have used  

this GRIMM instrument which houses many  these parts or components like EDM,  

this field housing where the instrument can  be put in, then this is the dust monitor,  

which monitor the particulate matter and  you can see like there is a connecting  

cable and then there is a filter paper with a  small size which is put into this instrument  

and data storage that memory card is there and  this is the battery which is used if there is no  

current available, power available there. Then if we look into dust monitor, so the front  

panel houses this LCD panel as well as the keypad  here, then this is the slot for data storage that  

particular card, then sample inlet is  there at four number where air inflows  

and analogue input 5 number, 6 is connecting with  the main adapter. And then interface port is the  

7 number which can be used for connecting  with the like desktop computer.  

Back panel has a space for this putting filter  paper and then there are different like for cable  

and other outlet is also there. So, all these  parts are on the backside of the instrument.  

And the basic principle is which is used for this  spectrometer they use the light scattering by the  

single particle. So, each particle that is  why this instrument gives not only the mass  

concentration, but count also, count means number  of the particles. So, count is also available in  

this particular spectrometer. So, this is the  way light scattering is there and the light  

scattering is detected by some method which  we can discuss here, detector is there.  

So, at the 90 degree the laser past so, when it  strikes with the particle it scatters the light  

and then through mirror it is reflected  and detector detects it and then that  

is monitored or that is stored accordingly  the number of particles and then the mass  

concentration can also be monitored. When we do the monitoring. So, basically  

the filter paper we should particularly  be careful about how to put it so remove  

using these tweezers the old one and then clean  it very properly and then put a new filter paper  

and it has to be weighed also 3 times so, that  because it is small, so the average weight is  

taken after weighing it for 3 times and  then monitoring is to be done.  

When data is taken into the desktop and  data as I said, it can be like particle  

per litre count means how many particles are  there in per litre, or microgram per cubic metre,  

the mass concentration can also be there. So,  this is the way data is transferred to the laptop  

or desktop and the software is there its own  software is there which gives us different  

buttons like we can select the  port, the time interval, all those  

things can be set to start the monitoring. So, you can see here the scan ports are selected,  

then it can automatically take which  particular port it is using otherwise manually  

we can give the name of this particular port and  this is the device which can give the display of  

this particular port related information. Then time interval can be set like from 6 seconds  

to 1-hour huge range is there. So, depending  upon the necessity, we can select how much  

at the what time interval we need data to be  stored like 5 minutes each or each 10 minutes  

or something like that. So, there is one need of  synchronise of the device time with the PC time so  

that there is no error of the time recording.  So, every 3 months they should be basically  

synchronised otherwise, if a site is changing,  time zone is changing particularly in time zone  

then you can synchronise it more frequently. Then if we took into this user settings,  

you can see how this is taken all these parameters  and headers are there and spreadsheet files are  

created basically like Excel etc. So,  that data analysis is very easy.  

Now, this is the button when we start  monitoring. So, the start device button is  

to be clicked and then this instrument starts  functioning and recording the data.  

Well after that when monitoring is  complete, then a stop device button can be  

pressed and data is stored and then data can be  taken whatever time interval we have selected  

and it can be transferred to the PC. So, this is the way data is collected basically  

different columns are there and then whether it  is count or whether it is mass concentration,  

we can select according to the requirement. We can analyse the data at per like  

time interval like particulate matter and mass  concentration or count. So, we can analyse and  

see how data is varying from time to time. So, these are the software of the spectrometer,  

which we are using. So, control software is there  which can give different kinds of possibilities  

and as per the site where we have monitored  data is transferred to the particular file  

and then it is analysed later on. So, here we present the short video  

illustrating the sampling and analysis of  particulate matter especially PM10 and PM2.5  

using a spectrometer. So, now you can compare  the high-volume sampler and a spectrometer,  

how do they function, what is their difference  in the procedures and whether one is robust or  

second is robust, and the possibilities the range  like it can also give PM1 etc and this video has  

been recorded in air pollution laboratory of  Civil Engineering Department in IIT Roorkee. So,  

enjoy the video and learn about the PM10 and  PM2.5 monitoring using spectrometer.  

Narrator: Good afternoon everyone. And I  welcome you all in this lab-based series of  

this lecture for NPTEL. And this is the last  lecture in the lab base measurements. And today  

we will be discussing on the sampling analysis  of PM10, PM2.5, PM1 using the GRIMM model.  

And for that we will be using this  apparatus that is the GRIMM EDM,  

EDM 164 that is Environmental Dust Monitor  and in that it is the field housing and this  

is the spectrometer and this is the memory card  which has been inserted in the spectrometer. So,  

let me just give you a quick intro of this, the  parts of this field housing and the spectrometer  

so as you can see this field housing here we  are placing the spectrometer right now.  

So, this is the spectrometer and this is the front  panel of the spectrometer, here you can see this  

LCD screen where we are seeing the readings  of all the PM10 PM2.5 all the particles and  

these are the control buttons, where we are  using these buttons we are controlling this  

spectrometer and this is the sample  inlet. So, in this sample inlet this  

sampling pipe is being fitted in this  spectrometer and this spectrometer is  

being placed in this field housing. Let me just give you the intro of this back panel,  

in back panel you can see that lock is there,  if you open this lock there is a PTFE filter.  

So, this PTFE filter this let me tell you this  spectrometer or EDM 164 can monitor or sample  

the PM10, PM2.5 using the two modes that is by the  optical particle counter and by the gravimetric.  

So, optical particle counter can  be attained using the spectrometer  

and also using the gravimetric analysis you can  weigh this PTFE filter and you can just analyse  

or sample the PM2.5 sample. So, after this taking  the readings you can weigh this PTFE filter before  

the sampling and after the sampling then  you can analyse the PM2.5 particles.  

So, you can see we are placing the  PTFE filter using these forceps  

and it is so placed that all the four points I  hope you are able to see these four points this 1,  

2, 3, 4 actually it is placed this PTFE filter is  placed this side, so it is so placed there like  

that these four points so that is 1, 2, 3,  4 these four points should be visible. So,  

after placing this filter we have to play close  this panel. So, after this closing the panel and  

assembling that this PTFE filter your spectrometer  is ready to be placed in the field housing.  

So, let me just place this spectrophotometer and  one more thing that is this spectrophotometer will  

be attached with the system and software  is provided for monitoring the particles  

and this software is also provided by the GRIMM  model and this system and this spectrometer  

is attached using this RS 232 cable. So, let me just attach all the things,  

so as you can see that the spectrometer is fitted  in this field housing and it is connected with  

this system using this RS 232 cable and the  field this sample pipe that is placed in this  

sample inlet that the port where I have shown  earlier, so let me just on the system.  

So, as soon as I on the system I hope you are  able to see that right now if not I will just let  

me just tell you as you are on the system you  will be seeing the model name first and then  

the date and time we are displayed in this LCD  screen and then thereafter the available memory  

that how much duration you can go for measurement  on analysis that is being displayed and after that  

it will ask you to this have  you change the filter or not.  

So, in response you have to just press this plus  button in the spectrometer for a few seconds.  

So, after hearing this beep sound the spectrometer  will go for self-test and the self-test is  

for 30 seconds and after self-test it will start  measuring the particles and it will be showing the  

counts per litre in this spectrometer the  units are in it is in counts per meter.  

I hope you can see right  now, it has being starting,  

I have received a signal like self-test is okay.  So, after receiving the signal of self-test is,  

you can see that a PM10 and PM2.5  

these two particles are being  displayed in this spectrometer.  

So, now spectrometer is started now we need  to configure the spectrometer according to our  

requirements and for that we have to go for  conferring the spectrometer using the system. So,  

this is the software which is provided by the  GRIMM. So, let me just give you the hands on how  

to measure or monitor the PM10, PM2.5 and  PM1 samples using this software.  

So, this is the software provided by the GRIMM  as you can see this is the UI of the software and  

here you can see different kinds  of options are available this is,  

first is the control panel next is to overview  so, as soon as I connect the software then  

it will be showing other options as well. So, here you can see you have to first select  

the ports or you have to scan the ports,  if you know already the port is there,  

then you can directly or manually select the  port right now I am clicking on this scan port,  

as you can see, it is detected the COM 3 port  that is the GRIMM port so the port is already  

selected. So, now you have to simply click on this  connection to device so while connecting with this  

software and the code you will be hearing some  sounds from the spectrometer as well. So, I have  

got the message that device has connected. So, simply you have to click on exit now  

you can see it is searching for some  analogue sensors and reading the data  

it will take a while, so the port is now selected  that is COM3 and you can see the model and serial  

number is all the details are there. Next step is to decide the time interval. So,  

as you can see, the time interval is shown  is you have to set the time interval. So,  

the range varies from 6 seconds to 60 minutes or  you can say 1 hour. So right now, I am selecting  

the 6 seconds and as per the requirements you  can select any of the options available right  

now I am selecting 6 seconds and I am clicking on  the initialise, that the time interval has been  

set, now I simply click on exit. Now, you have to sync the time of this  

spectrometer or you can say the optical particle  counter, you have to sync the time with your PC  

time. So, you can see that you can see the option  that is to get the current PC time and OPC time  

is the Optical Particle Count time. So, that  will sync the PC time with your Optical Particle  

Count OPC time. Here I have got the message time  on OPC is synchronised with your PC time. So,  

the date and time which were we were seeing in  the spectrometer that is now synced with your  

PC time. Now, I am clicking on exit. Now, next step is the user setting. So, here  

we are giving the details of the output file.  Right now, this is test 8, for example, I am just  

giving the name as test 10, so you can see all the  relevant files, the mass file, the count files,  

the dM files and the log files all are being set  up accordingly. And also, you can add the details  

like comments. So meanwhile, I have just set that  normal conditions. And I have added the user name,  

as my name is Anurag and also location. So,  right now, we are just taking the readings on air  

pollution lab at IIT Roorkee. So, I have selected  that location, I will click on OK.  

Now, by defining the user setting now you can  start the device message is being displayed  

in the bottom you can see measurement is in  progress. So, yes you can see the measurement  

is now being started and in this port telegram,  in this window you will be able to see as soon as  

the reading has been started. So right now it is  preparing to start the taking the readings there  

it will take a while. So, the next message  you can see this data storage in progress.  

So, as soon as it starts taking the reading,  you will be hearing a sound for a spectrometer  

and all the other options like control, overview,  and distribution table. Now, you can see that all  

the options are now available, you can toggle  with all the tabs. So, let me just give you an  

idea of all the tabs. So, control tab we already discussed.  

The next tab is the overview tab. So, in overview  tab, you can see all the details of your readings  

counts like what are the particles which are  less than 1 micrometre what are the particles  

which are greater than 1 micrometre  and total count of the particles total  

suspended particles PM10, PM2.5, PM1 and other  particles like it is classified as inhalable,  

thoracic and Alveolic. So, all the  particles like the details of the particle  

as shown here as an overview,  in this particular time.  

So, coming to the next step that is  distribution. In distribution tab you can see  

a log table is being shown. So, in this  first table, that is the log table.  

You can see the X axis you can see the particle  diameter or particle sizes and in Y axis, you  

can see the this microgram (())(20:04). And in this you can see the area divided by this  

volume of the air being sucked by this  sample pipe and in first tab you will  

be able to see the counts per litre. So, this log graph is being shown in distribution  

tab, in the next tab you can see the live  reading you can be able to observe that  

it every 6 seconds that is the what interval we  have decided at every 6 seconds it is showing the  

readings of all the particles. And in the first tab you can see  

the counts per litre in the next tab you can  we will be able to see the PM10, PM2.5, PM1  

and other particles that is the indoor air quality  you can say. So, in this here you will be able to  

see in microgram per metre cube the unit. And coming to the next one  

now this is the graphical presentation of  we were seeing earlier that is in tabular  

form and this is the graphical form. That is count per unit of mass is being seen  

and this one is particulate matter and next one  is IAQ. So, in particulate matter this PM10,  

PM2.5, PM1 are being shown in this indoor air  quality this Inhalable, Thoracic, Alveolic,  

so these are related to this particle is related  to the size ranging from according to these  

organs present in the lungs. So, according to the  size of whichever be the sizes like in Alveolic  

part there is some size ranges and according  to that this measurement is being done. So,  

that particular part is called as Alveolic. In next step, that is the statistics,  

you can see the values which we are measuring and  then all the again the units are there that is  

counts per litre and microgram per metre cube. So,  you can calculate the stats using this particular  

time. And also, you can plot the graph now, this  

showing the stats of this particular measurement.  So, boxplot or whisker plot you can say, and at 5  

percent confidence interval at 95 percent they are  being plotted. So, you can see the PM10, PM2.5,  

PM1 are being plotted. So, in this whisker plot  you can see this lower part is the lowest range,  

the bottom part and this particular line shows  the uppermost range and this box, this box shows  

the interval, confidence interval of 5 percent and  95 percent that is being shown and that this line  

shows the median, median of the readings and the  values you can observe in this particular window.  

So, after this what we are going to do, you  can also save all the graphics or all the graph  

right now, it any particular instant. So, this is all about the, this line monitoring  

real time monitoring. So, now we have to save the  data. So, for saving data you have to first stop  

the device. So, after stopping the device, what  do we have saved that I hope you are remembering  

that we have saved by using the name test 10  that is being saved. So, the question arises  

from this like for going for a field condition  we cannot take our system and for example,  

if we want to monitor the particles, for 8 hours  or 24 hours or maybe any of the requirements.  

So, in that case, what we are doing, we are simply  connecting the device and initialising data using  

the software. So, after initialising the software  starting the device, we can disconnect the cable,  

this device will still be working and the data  will be stored in the memory card. So, sampling  

time is completed for example, we are taking the  reading for 8 hours. So, after starting the device  

and after completion, you can simply turn off  the spectrometer using this on off button that  

is already in the inner spectrometer. So, using  that button you can simply off the device.  

And now to extract what data has been saved  you can simply click on the external memory.  

So, it will ask that whether the data has  been saved in SD card or that card that is  

known as SRAM card or PCMCIA card. So, right now, I am clicking on SRAM card. So,  

again that particular COM port has been selected.  Now, you have to go for read memory card after  

clicking on read memory card it will read the  card data it will take a while the data will be  

downloaded one more information about  data if you are going for fresh reading.  

I would recommend that clear the memory card  for going for fresh reading so that the previous  

reading should not be altered, you can see  memory card is being downloaded.  

So, after this data has been downloaded that data  can be converted into spreadsheet format using  

these options, so as soon as I click on data  convert to spreadsheet format, this particular  

window opens and you can see the whichever data  we have recorded, right now that you can select  

the data using this toggle keys that is present  here. So right now, I am selecting the fourth one,  

and you have to just give a name. So again, I am giving the name as test10_1.  

Now, I will click on the start conversion  data has been is already been converted.  

So, let us assume that you have converted the  data and we have obtained the 8 hours of reading  

in particular spreadsheet format. So  also, you can import that particular  

spreadsheet in this software also. So, for that we can go for open files,  

and open files you can see right  now it is bar by default, taking the  

file which I have already saved, okay also you  can select or browse at particular locations. So,  

right now I am again selecting that  file just for information.  

And you can click on the open files with  the software and you can click on exit. So,  

you can see now that all the readings which you  have taken and that is present here. So, this is  

the procedure by which you can measure the PM10,  PM2.5 and PM1 using this GRIMM model. So, this  

is software all about the software, thank you. Professor Bhola Ram Gurjar: So, you have seen and  

you know how to use the spectrometer. So, this  is a versatile instrument which can give you  

count as well as mass concentration  of particulate matter PM2.5, PM1, PM10  

huge range is there as I said, and all these data  are very important because whenever we want to do  

so, suppose meant or identification of  different sources where they are coming from  

and if we want to relate different kind  of concentrations of PM1 or PM2.5 etc,  

then we need these kinds of data and also to  compare whether it is violating the standards  

or not, so monitoring is very much needed.  So, this is all and this is the last lecture  

of this particular course. These are the references which we  

have used for this particular lecture. So, I  take this opportunity to thank all of you who  

took so keen interest in this particular course,  we enjoyed your interaction through emails etc.  

And I thank E-Learning centre of IIT Roorkee  specially Binoy to schedule lecture recording  

times as per our convenience and I also thank  TAs Anurag and Gaurav and other students like  

Ria and Apshay and Rahul they have also  contributed a lot in this particular course.  

So, thanks all and I wish you all the best  for your pursuits regarding air pollution  

control and air pollution studies, whether you are  studying as a student or whether you are trying to  

implement this knowledge in the field. So, all  the best for your pursuits. And thanks again.