Empirical studies on the effect of electromagnetic radiation from multiple sources in Dhaka

Just after the invention of electricity by Michael Faraday, there has been a revolution in the communication technology, which lead to the invention of radio, television, radar, satellite, and mobile. While these machines transformed our life high quality, safer and simpler, they have been associated with alarming probable health hazards owing to their electromagnetic radiation (EMR) emission. Couple of cases it has been reported by personals regarding various health related issues relating to exposure on electromagnetic field (EMF) and EMR. Although couple of persons showed light symptoms and respond by avoiding the electrical field (EF) and EMR fields as much as possible, some others are so much affected that they have changed their entire lifestyle. In this paper, empirical survey study has been carried out in the laboratories of Daffodil International University (DIU) main and permanent campus. It was found that some of the instrument had higher EMFs. The findings from this survey may be helpful for the students to take precautionary measurement who work for long duration in the various laboratories for their practical classes and for the users of the domestic appliances as well as office equipment and industrial instruments.


INTRODUCTION
There is no doubt that electricity is the main factor for today's civilization. Now a days the power from the electricity is the primary source of energy for the contemporary technological world. The electrical power consists of two fields: electrical field (EF) and magnetic field (MF), generally known as electromagnetic field (EMF) which is very much useful. But at the same time, one should be aware about the harmful/ bad effects of radiation from the EMF which is known as electromagnetic radiation (EMR) or nonionizing radiation (NIR). It is narrative that high power transmission line, video display unit, computer, laptop, fridge, router, many other home appliances, office equipment, Telecommunication equipment, also Laboratory equipment in every schools, colleges and university, radiate energy whatever small it may be [1]- [4]. These high frequency (HF), low frequency (LF) and extremely low frequency (ELF) EMF instruments are reported to be very harmful for human body/living system and has effect on lower-level animals. The MF has more harmful effect than the EF. Because the EF inside human body discharges through ground and other materials but the MF do not discharge from the body, thus generating various health problems, causing sufferings for the users. Because of its harmful effects, scientists have named this EMF/EMR as a silent killer. The long-time use/long time exposure to EMF/EMR has bad effects of the 118 committee for non-ionizing radiation protection (ICNIRP)/ITU/IEEE. If the radiation level is higher than the permissible dose, students may be affected by the EMR causing various diseases/sufferings as already reported by the scientists/engineers from many countries. The findings from this survey will put some light on how to take precautionary measurement from EMR emitted from various sources.

RESEARCH METHOD
In this survey measurement of various laboratory equipments from DIU was carried out. measurements on EF, MF and radiated power from every instrument were taken. The present work mainly involved with the measurement of EF, MF, signal power and threshold distance from electrical and electronics devices in laboratory instruments of multiple departmental laboratories of DIU. The highest values as well as the threshold distance were noted down. Measurements from various devices in the laboratories were also carried out where the students spend long time every day. Measurement was taken around the device (front, back, left, right, top and bottom). Magnetic meter from magnetic sciences international (MSI) was used to measure magnetic field. Then threshold distance of the radiation was measured by Coghill field mouse. Also, the measurement of the EF, MF and power was done by electrosmog meter.
A power density meter named Electro-smog meter (Model no. CORNET®ED-78SPlus) was utilized for measuring power density level, Electromagnetic wave field strength, and low frequency MF (Tesla, Gauss) for living environment [57]. It has LF bandwidth of 50 Hz to 10 kHz having sensitivity of 0.1-60 μT and RF bandwidth of 100 MHz to 8 GHz having high sensitivity (0.5 μW/m 2 to 1.8 W/m 2 ). All main campus data are measured by this meter. This meter gives a pointed value. A Coghill field mouse for biohazards awareness was used for detecting the threshold levels for electric and MF nearby to the device. The threshold voltage setup internal in the Coghill Field Mouse is as per ICNIRP.
Digital EMF meter: All the permanent campus data are measured by this meter. It is a high range frequency meter and shows without pointed value. This EMF meter can measure and display magnetic field, EF, and RF strength simultaneously. The unit of measurement are conveyed in units of magnetic and electrical field strength and power density.

RESULTS AND ANALYSIS
This main campus data was taken from power supply for PCs, UPS, and some departmental laboratories. These data and analyses are given below. This Figure 1 contains the main campus CSE, computing and information system (CIS), software engineering (SWE), ETE, EEE all personal computers (PC, especially CPU) data. There were a total 545 PCs in the main campus and data were taken from these labs. These surveys were carried out value for threshold distance from all the PCs. Measured value is applicable for EF only because MF was detected everywhere inside the laboratory room. The EF threshold values ranged from 12.7 to 64.0 cm. This Figure 2 contains the main campus CSE, CIS, SWE, ETE, EEE all uninterrupted power supply (UPS) data. There are 236 UPS data taken from these labs in main campus. The MF values in most cases were 60 µT as the maximum value that can be measured by the MF detector. So, the MF values in most cases were more than that value. The MF and EF threshold distances were also measured for all the UPS. In all cases, the MF threshold distance shown were over the threshold values everywhere inside the labs. The EF threshold values ranged from 3 cm to 13.5 cm. Figure 3 shows oscilloscopes of ETE lab of main campus. ETE lab has two types of oscilloscopes one is analog and another one is digital oscilloscope. Digital oscilloscope is enormously comfortable compared to the analog oscilloscope. Analog device has higher value of electromagnetic field. Amongst the 17 oscilloscopes, most of them have lowered values of both EF and MF. The oscilloscopes were manufactured ranging from year 2014 to 2017.

Figure 2. Data from numerous UPS of main campus of DIU
The EMF threshold distance value was taken for both digital and analog oscilloscope which has shown EF lowest 7.62 cm to highest 60.96 cm. But MF was detected all around inside the lab room. This may may be due to the electrical wiring running through the walls, ceilings and floors of the labs as a result, there were interfering of MFs from all the sides. Given in Figure 4, function generator is very much used in circuit laboratory and electronics laboratory. The cause of low EF and MF values was that the readings were taken at low frequencies that is why the field is exceptionally low. When the frequency was varied to higher values, then the instrument measured higher values of EF and MF.
The EF threshold distances were also measured for all the UPS. The MF threshold distance went over the threshold values and everywhere inside the labs were found over the permissible label. The EF threshold values range 15.24 cm.  Figure 5 is that the DC power supply do not shut down during the class hour. Therefore, after one and half hour this device generates hit, and as a result it was found that MF was much higher compared to the EF and radiated power. In all the cases MF crossed the MPD inside the laboratory room. But EF threshold distance value from DC power supply was 97.5 cm.  Figure 6 shows six voltage stabilizers in ETE labs of main campus. The EF and the radiated power values are incredibly low and within threshold limit. The MF values were very high and for one voltage stabilizer was 45.3 µT, and the others were less than this value. In all the voltage stabilizer instruments EF threshold distance noted value up to 94.5 cm, which may cause harm to the users. Figure 7 shows the trainer board which is also a low voltage operated device. We know that low voltage and low current, low EF, and magnetic field. ETE laboratory were covered by MF but the measured EF from the trainer board was 94.5 cm.  4 5 6 7 8 9 10 11 12 13 14 15 16 17 18  Permanent campus data of various instruments obtained from EEE, textile engineering, and civil engineering laboratories are given in Figure 8 until Figure 10. Figure 8 shows EF (V/m), MF (µT), and radiated power (µW/cm 2 ) of equipment from the permanent campus EEE lab. This lab consisted of instruments DC supply, DC generator, Induction motor, auto recloser, transformer overhead protection, DC supply, Split phase motor, Power supply, electrodynamo meter, single phase transformer, resistive load, induction load, system power, DC motor control module, DC supply, DC module, system power, and programmable logic controllers (PLC). All these instruments were manufactured recently in the year 2019. The system power has a remarkably high EF (1635 V/m), including MF (201.1 µT) as well as the radiative power (71.4 µW/cm 2 ). The highest radiative power is seen for the two DC power supplies (85.6 µW/cm 2 ). Precautions must be taken for the system power otherwise it may cause harm to the students/ users. The threshold values of EEE lab were taken for every instrument EF 60.96 cm and MF was detected everywhere inside the laboratory room.  123 Figure 10 shows EF (V/m), MF (µT), and radiated power (µW/cm 2 ) of equipment from the permanent campus civil engineering lab. This lab consisted of equipment like hot air oven, Incubator, universal testing machine, concrete core cutter, Los Angels abrasion machine, concrete mixture machine, and cement testing machine. All these equipments were manufactured recently in the year 2019. The incubator has an exceedingly high EF (814 V/m), but MF is low (0.011 µT) as well as the radiative power (27.4 µW/cm 2 ). EF for hot air oven is also vey high. EF of civil engineering labs had much higher values compared to all other laboratories in DIU.
The threshold distance of EF hot air oven was 66.04 cm, the incubator 60.96 cm, universal testing machine 53.34 cm, concrete core cutter 78.74 cm, Los Angels Abrasion machine 7.62 cm, concrete mixture machine 7.61 cm, cement testing machine 20.32 cm. The MF was found to be almost everywhere.

DISCUSSION
The EMF is all around us and it causes health hazard from various sources or from electronic equipment. So, people should be aware of this, and it is essential to be informed about the detrimental outcomes of EMR/NIR on living system and on the surroundings. The scientists and engineers should be more active to find out the appropriate solutions for reducing or managing the hazards of non-ionizing radiation before it causes great hazards.
From the EMR measurement results given in Figures 1 to 10, it was obtained that the MF levels are much greater compared to the threshold value. Due to the type of the wiring both in the floor and ceiling, all the rooms had greater EFs than threshold level. Students stay in the laboratory rooms on an average of 3 to 5 hours. So, the value of EMF level, the amount of radiation from various sources, position of equipment must be set up properly, so that there is minimum radiation and minimum interference from EMF.
From the observations and empirical studies, it was found that EMR has adverse effect on living systems, especially people working/living near/under high frequency like laboratories and electrical industries. Most of the people were suffering from various diseases, the common disease found, were insomnia, headache, indigestion, hearing problem, eye itching. It was found that longer the exposure time, more is the sufferings and some of the users complained about their sufferings in their conjugal life.
EMR are capable of initiating consequences in biological organisms. Everyone is endangered to multiple types of EMR daily, as the whole world is covered with EMF from satellites and various other sources. This would not account for the introductory and administrative steps to manage the manufacture, allocation, and usage of EMR for telecommunications.
WHO has established the ICNIRP in 1996 to monitor, regulate and advice on EMF. Many countries of the world including Bangladesh has adopted the Non-Ionizing Radiation Protection Regulations 1998/2018 by ICNIRP effective from November 2019. Bangladesh has adopted ICNIRP Guidelines without any modification or any change, but it should be modified according to the climate and environmental/geographical condition of Bangladesh. India also has adopted the same Regulation in 2012 but they have modified the recommended values to the 1/10th of that values suggested by ICNIRP.

CONCLUSION
This survey points out that in most situations the MF had exceeded the threshold level. The MF and EF had a greater threshold value in multiple instruments of the laboratory. The MF highest exposure was close to 60 µT in numerous situations. Electrical wiring ought to be performed as per the Building Code 2012. This survey can be useful as a precautionary step for general users, workers in industries, service people, teachers, lab workers, students and the younger generation who might be affected tomorrow. This survey points out that EF and MF measured in the Permanent Campuss was many times higher than the Main Campus. Therefore, care should be taken to minimize the radiated EFand MF fields wherever possible.
The health hazards instigated by all these things, personals ought to be sensitive of them and preventive steps ought to be taken accordingly. It is essential to be familiar with the detrimental outcomes of EMR on living systems and on the environment that we are living in and to explore suitable remedial steps for reducing the risks of EMR as much as possible.
As MF is more damaging than EF, there ought to be a threshold level for the residential and occupational levels from 0.2 to 0.3 µT. This amount is worldwide established as accepted level in numerous countries. More studies and thorough observations for a longer period are required to learn more about the field which could led to some acceptable solutions of the various problems specially health hazards arising from the EMF radiation. In addition, certain regulations are necessary for the laboratories (medical, industrial, scientific) utilized for commercial and domestic purpose and the diversity of radiation emitting instruments and installations.
In this paper efforts have been put to focus on the effects of EMR from various sources specifically on the laboretory equipment where students spend a long hour during their study period in the school/ college/university. It will help the academic authority to think and modify the present working conditions prevailing in the respective laboretories to set up a better/safer working environment for the students.