PRE2020 3 Group4
Group members
| Name | Student ID | Department | Email address |
|---|---|---|---|
| Mark den Besten | 1022231 | Automotive Technology | m.d.besten@student.tue.nl |
| Yann van Eijk | 1454447 | Mechanical Engineering | j.h.m.v.eijk@student.tue.nl |
| Ilse Schuckman | 1239641 | Electrical Engineering | i.schuckman@student.tue.nl |
| Rik Schutte | 1005841 | Psychology & Technology | r.j.r.schutte@student.tue.nl |
| Roel Wijnands | 1235389 | Electrical Engineering | r.r.c.wijnands@student.tue.nl |
Problem statement
Every minute is crucial when providing aid to someone who has an out-of-hospital cardiac arrest (OHCA). The highest survival rates are achieved when the patients receive defibrillation as fast as possible (Jafri, 2021). The time it takes for an ambulance to arrive, however, is usually too long to ensure good survival odds for the patient (Solanki, 2017). In order to reduce the average time between an arrest and defibrillation, automatic external defibrillators (AEDs) are placed in public areas. These AEDs are placed in cabinets that are often locked, so they are protected from acts like vandalism. The people that can access them are usually the owner(s), their employees, and citizen responders. Citizen responders are people who have followed CPR and AED courses and are registered in a national database. When an OHCA occurs, nearby citizen responders are alerted via text message to the location of the closest AED and the place of the incident (Burgerhulpverlening 2021). They have an app on their phone which provides them with the code that unlocks the cabinet. However, because the situation is both stressful and extremely time-sensitive, the time and effort it takes to read and input a code correctly is unwanted. The aim of this project is to remove this process and thereby reduce the average time between an arrest and defibrillation.
How it currently works
HartslagNu is the paging system that calls up emergency responders via a message on the mobile phone to go to the scene in case of possible resuscitation. In many cases, emergency responders (Also known as "Burgerhulpverleners") are able to respond quicker to an emergency situation than the emergency services, due to the basic concept of coverage (work this out, or leave it out). It is important to be able to notify the emergency responders as quickly as possible, to keep this time advantage.
The current state of the HartslagNu system in the Netherlands is well seen from a technological standpoint. The user gets to enter their home and/or work address online or within the HartslagNu app, and based on that information the user can be contacted via SMS in the case of an emergency. In addition to this basic feature, the application also allows the user to turn on their location and let the application track their GPS signal. When the user is near an emergency location, the application sends them a notification containing the location of a possible resuscitation. It is important to make the distinction between the SMS-based function and the application-based function, these two can work separately from each other and in addition to each other. HartslagNu thus assumes that everyone has a mobile phone, but not everyone (always) has an internet connection on his/her phone. To use the application the user has to have an internet connection and allow for the app to send push notifications.
Emergency responders are trained to start up the resuscitation, preferably using an AED (Automatic External Defibrillator). These AEDs are publically available all over the Netherlands and are usually protected by a pin code on a so-called AED box. The Emergency responders are able to get access to this AED by retrieving the pin code either via SMS or in the application. This, however, takes time and sometimes does not work at all. This time loss can result in the loss of lives or the cause of brain damage at the victims' end. This is where an adaption to the current system can be made and what this project is all about.
Objectives
The main objective is to design a new locking system for a publicly placed AED. First, anyone with the right clearance has to be able to access the AED as fast as possible, without having to do any additional actions like filling in a code. Second, the AED must be protected from incidents like vandalism and should not be accessible to anyone that is not authorized to. To meet these requirements, the design will include an app on the smartphone of someone who should have access and a way to determine the distance between this person and the AED. When someone has the app and is physically close to the AED, the cabinet should be unlocked automatically without any other user input needed.
Users
There are two main users that have to interact with the AED locker.
Firstly, the first responders to an emergency, the so-called “burgerhulpverleners”. A first responder gets a notification on his cellphone and has to, as quickly as possible, get an AED to the victim that is having an emergency. An AED should get to the victim within 6 minutes (bhvnederland, 2018), every second counts. A first responder should therefore have quick and easy access to the AED. Quickly, because lives are at stake. Easily, because in the heat of the moment a first responder might not think logically and slowly. The first responder should not have to think about getting a door unlocked.
Secondly, the owners and maintainers of the AED and its locker. To put an AED outside is voluntary. Therefore when an AED is damaged or lost it’s a loss for the owner. An AED should be sufficiently protected from malicious users. Right now a pin code is used for this (HartslagNu, 2021). The maintainers also would like to keep their costs and maintenance low. So it should not cost a lot extra. Additionally, these owners already have a locker that functions well. They do not want to buy a new one before the old one is written off.
Additionally, there is the owner of the app and database of all the AEDs in the Netherlands, HarstslagNu. If we improve the interaction between the AED lockers and their app. It should be easy to implement. There should also be some new entry for their database, of what type of locker it is. Especially in the beginning when not all lockers are upgraded. The app should know what kind of locking system the locker uses.
To further detail the user requirements, the following user scenarios were created:
Dirk
Dirk is a 32-year-old man living in Helmond. He is a licensed aid worker and is part of the NIBHV network (the national aid worker network). On a given Saturday, he was taking a walk in the park when he got a message on his phone. A text from HartslagNu, that someone in the area was having a heart attack. He opens the HartslagNu app and accepts the call for action. The app shows him the route to the afflicted person as well as the nearest AED for him to take with him. The app also gives him the code to open the box which houses the AED that he is assigned to. He hurries to the AED as quickly as possible and gets there in 3 minutes. The route shows that it is another 2 minutes to get to the victim. As he knows from his training, he should get there within 6 minutes as the victim might end up with permanent brain damage otherwise. This gives him 1 minute at most to get the AED and hurry along.
However, when he arrives at the AED box, there is a problem. The box is locked and requires a pin code to open. He remembers that the app should have a code for him to unlock the box, so he grabs his phone and opens the app. After looking at the app, he cannot find the code. In the meantime, another responder shows up and starts looking for the code too. After 2 minutes, they finally find the code and open the box. After grabbing the AED, they hurry towards the victim together. They arrive at the scene 7 minutes after the call was made. When they want to start helping the victim, they hear sirens coming closer. The ambulance shows up and takes over the care for the victim. So, in the end, Dirk and the other responder could not do anything and go back to where they got the AED from to return it.
Mandy
Mandy is a 43-year-old woman living in Rotterdam. She owns a small store in the area and is also a certified company aid worker. She is part of the HartslagNu network and was looking through the AEDs in the area when she noticed a lack of AEDs in the area around her store. Because of this, she decides to invest in an AED at the shop. She intends for the AED to be placed just outside the shop so it can be utilized for general emergencies. One of her worries is that certain people, say a drunk man after a night out, would steal the AED, so she decides to get an AED with a lock. The Dutch heart foundation advises her to get one with a pin code as it is more resilient against weather conditions.
To fund this endeavour, she approaches the municipality. She poses her problem and requests some financial aid to make this happen, as it would benefit the entire neighbourhood. The council in Rotterdam agrees and wants to cover half the costs of the AED. With half the costs dealt with, Mandy can afford to get the AED installed. To make it easier on herself, she arranges one with self-testing capabilities. This causes the AED to send a message to her over Wi-Fi when something is wrong. Apart from that, maintenance only involves changing out batteries which is done by the company she bought the AED from. One afternoon, someone rushed over to her AED, and took it out of the box. After about 10 minutes it was returned without issue. That same night, she saw a story on the local news about some being reanimated using an AED. This proved to Mandy that having an AED installed is definitely worth it.
User requirements
Brain damage can occur within 6 minutes of cardiac arrest (bhvnederland, 2018). Considering the average response time for civilian first responders is between 5.5 and 7.5 minutes (Dagblad van het Noorden, 2019), every second counts. As such, the box housing the AED should open in no less than 15 seconds to ensure quick access.
To make it easy to open the box, it should not require any extra operations from the user. So, during an emergency, opening the app should not be required to open the box.
The users also require the AED to still be in the box. This involves creating a tamper-resilient box with a robust locking mechanism that keeps unwanted people out while maintaining ease of use for the certified users. Since it is connected to an online system, this framework also requires tight security such that people cannot falsely certify themselves and gain access to the AED.
In case of a bug in the app or the system malfunctioning, an alternative way of opening the box containing the AED needs to be present as well. This is also for users that do not wish to use the app, whether that is because of a lack of technological understanding or a desire to protect all their data. As such, the new way of opening the box needs to be an addition rather than a replacement.
When there is no active emergency, the lock should not open, even when certified users of the app walk past. This excludes maintenance. This is to prevent the box from randomly opening when users walk past it unknowingly.
When the AED has been removed from the box, it should be easy for the first responder to return the AED to the box and to close and lock the box. The box should not be locked when the AED is not present in it. This prevents the box from locking itself when the AED is not contained in it. This way the owner can perform the mandatory check-up of the AED.
For the owners, it is vital that the system is easy to be installed and requires very little maintenance. High levels of upkeep would be bothersome for the owners and would also disincentivize people from getting AEDs in the first place. While an initial installation has to be done, including the necessary wiring, further upkeep must be kept at a minimum. Since the AED needs to be tested once a year, the lock should also be tested once a year at a minimum.
The price of this newly developed technology should be reduced to encourage buyers to implement this device on their AEDs. The cost for upkeep should also not be increased by more than 3 percent of the existing cost. This is due to the high cost of upkeep as is (Medisol), and people might get deterred from installing an AED if the cost becomes even higher.
User survey
In order to test the main plan of opening the AED cabinets from a remote location, the opinions of the users were needed. In order to reach out to the users, some different methods were tested. The first idea was to simply reach out to HartslagNu and ask if they were willing to spread the survey via their social media accounts. However, HartslagNu was not willing to cooperate since they also use their social media accounts to spread surveys for themselves, and they did not want any confusion under their users by spreading a survey from a third party. This was a bit of a disappointment, and after trying to reach out to local foundations that are in close contact with HartslagNu and getting the same response, we tried to reach out to the users directly. More can be read on this in te section 'contact with the users'.
Voluntary first responders
Q1: How long have you been a voluntary first responder?
Q2: How often have you retrieved an AED?
Q3: How are you notified by HartslagNu of a possible emergency?
Q4: Did you ever have to use an AED where a pincode was needed to access it?
Q5: If yes, did you encounter any difficulties while accessing the AED?
Only 2 responses stating: not applicable
Q6: Is there anything you would change about the current methods used to access locked AEDs?
1 response stating: Our AED cabinets are not locked.
Q7: If you were called to retrieve an AED, do you think the amount of time and/or stress would be significantly reduced if a locked cabinet were unlocked remotely so you no longer have to enter a pincode?
AED owners
Q1: For how long have you owned an AED?
Q2: Is your AED placed in a cabinet that requires a pincode to open?
Q3: Why did or did you not choose this option?
3 responses in the trend: 'It was the advice of the local heart foundation.'
2 responses in the trend: 'Because every second counts.'
1 elucidation: 'From the 72 AED cabinets we oversee, only 1 has been vandalized and 1 disappeared over a span of 14 years. Putting the cabinet behind a lock is in our eyes unnecessary.'
Q4: Has your cabinet and/or AED ever been damaged due to (attempted) vandalism or theft?
Q5: In regards to the security of your AED, how would you feel if your cabinet was unlocked remotely at the same time as the voluntary first responders are notified of an incident?
1 response: 'I am fine with it.'
Survey conclusion
Burgerhulpverleners
The burgerhulpverleners reached with the survey seem to be very experienced, with 66,7% of them being a burgerhulpverlener for 6 years or more. However, it seems that they (luckily) do not have to come into action that much since question 2 indicates that they retrieved an AED only 0 up to 5 times. In hindsight, the answers for this question should be provided differently, since now it is unclear whether they have retrieved an AED even once. This could be improved by adding the option '0 times' as a stand-alone answer. It also seems that not all burgerhulpverleners are notified by HartslagNu, with 33,3 percent saying they are not notified, 16,7 percent saying they no longer are notified, and only 50 percent being notified either via SMS or via SMS and the app. This can be due to the confusion of the abbreviation 'BHV', in dutch this commonly stands for bedrijfshulpverlener (emergency response worker), but in this case, it stands for burgerhulpverlener (voluntary first responders). Bedrijfhulpverleners are employees that are trained to provide first aid in case of an accident on the work floor. They are not signed up for the HartslagNu paging system. A possible explanation for the number of respondents not signed up for notifications from HartslagNu could be due to this confusion. The answers to question 4 also indicate that the ideal target audience was unfortunately not reached. Questions 5 and 6 are hard to discuss due to the lack of answers to those questions. The main gain from the survey under voluntary first responders is the answers to question 7. Here it can be seen that 83,3 percent of the respondents are in favor of opening locked cabinets from a remote location, with only 16,7 percent of the respondents not seeing any gain at all. This means there is no reason to cut the project short by saying that there is no need for it from the side of voluntary first respondents. This conclusion is very limited, and only based on a small number of respondents, so it should be taken with a grain of salt.
AED Owners
Most of our AED owner respondents seem to be in contact with Rooi Hartsafe. This is an indication that the answers to this survey are heavily based on the AED owners in the old municipality of Sint-Oedenrode. This, of course, is not ideal as this is not representative of the whole country of the Netherlands. Thus the main conclusion that can be made from this survey is that there are not enough respondents, and the respondents are not wide-spread. This does not mean the survey was useless. The survey did provide the insight that not all local heart foundations see the usefulness of locking the AED. This means that the solution is mainly based on bigger towns and cities, or other busy areas. the heart foundations in several cities were contacted but a response was not forthcoming. When continuing to contact the users, it is important that the users in denser areas are reached. Due to corona-virus measures and the unwillingness of the people in these areas to cooperate, their opinions have not yet been heard in the survey. It is therefore still unclear what their view on the topic is, based on the survey.
Contact with the users
Yann
Spreading of the survey
To collect as much data as possible we tried to spread the above-mentioned survey to as many people as possible. I myself started by contacting as many people I know via WhatsApp. Via this medium, I must have reached around 500-600 people, mostly via group-chats. This was, however, not very effective since the people who received the message were a random group of the population. This meant that the chance that one of them was either a 'burgerhulpverlener' or an owner of an AED was very small. After waiting for 24 hours the number of answers on the survey did not increase, so I concluded this had been ineffective.
Afterward, I tried to specifically reach out to AED owners in the region in an attempt to increase the chances of getting answers to the survey questions. For this, I used the sites of the foundations HartVeilig Den Bosch and Rooi Hartsafe. They offer education on resuscitation in the municipalities of s'-Hertogenbosch and Sint-Oedenrode (Meijerijstad) respectively. They also manage the spread of AEDs in their own municipality. A list of where AEDs can be found has been posted on their site, using this list, I contacted around 15 companies/individuals via either e-mail and/or phone number. I also contacted the foundations to ask for their own opinion and if they were willing to spread the survey. A list of the people contacted and their responses can be found below. I tried to contact small businesses and people I knew via the local football club etcetera. I also called 2 people who managed AEDs in private locations, Mr.Van Dongen and Mrs. Smits. With respect to their privacy, their contacts will not be included, as requested by themselves. I will include their answers to the basic questions in a later paragraph.
People contacted and reactions
| Contact | Reaction (y/n) | Notes |
|---|---|---|
| HartslagNu | Yes | They were not willing to spread the survey, I did get answers to the questions that I asked in the mail directly. They will be processed in a later section. |
| Stichting HartVeilig Den Bosch | ||
| Stichting Rooi Hartsafe | Yes | Due to interconnection with HartslagNu, they are not allowed to spread the survey. They did fill out the survey. |
| Goessens podologie | Yes | They replied mentioning that they do not have an AED on their location. They did think it was a good idea. |
| Fysiopraktijk RompertCentrum | ||
| Gemeente 's-Hertogenbosch | ||
| Ergotherapie helftheuvel | ||
| Mister design | ||
| Winkelcentrum arena | ||
| Noorderpoort samen doen | ||
| Sporthal Kienehoef | ||
| Woonmeij | ||
| Horecacentrum de Vriendschap | ||
| Zorgboederij Dommelhoeve | ||
| Camping Kienehoef | ||
| A. Kuis uitvaartverzorging | Yes | Mentioned that they filled in both parts. |
| Gemeentehuis Meijerijstad locatie Sint-Oedenrode | Yes | Said to contact the foundations active in the municipality. |
| Fysiotherapie Marie van Heijst | ||
| Acura |
After sending out e-mails to the last 9 locations, the responses for the AED owners went up by 3. It could be that this is pure coincidence, but to me, it seems that the people in small-town Sint-Oedenrode were more eager to help out than the people in 's-Hertogenbosch. In the end, I do believe that this method works, but it is very time-consuming.
Interview with Mr. Van Dongen and Mrs. Smits
I was able to interview 2 persons who put an AED on their resident houses. They both mentioned that they were willing to help, so I prepared some simple questions that could be answered quickly.
Q: "How long have you been in possession of an AED?"
Answer Mr. Van Dongen: "I've been in possession of an AED for 2.5 years."
Answer Mrs. Smits: "I've been in possession of an AED for a little over 1 year."
Q: "Why did you decide to obtain an AED?"
A,D: "My brother suffered from cardiac arrest, one of the reasons he could not be saved was the lack of AED availability. I decided to purchase this AED with the help of Hartsafe Rooi out of his legacy."
A,S: "It was brought to my attention by a friend of mine that there was a lack of AEDs in our neighborhood. Together we decided to do something for the district by purchasing one together. It is pure coincidence that the AED ended up at my house."
Q: "Was your AED ever victim of (attempted) theft or vandalism?"
A,D: "No."
A,S: "As far as I know not."
Q: "has your AED ever been retrieved for a potential resuscitation?"
A,D: "I live in a very quiet neighborhood, so luckily it has not been needed since I obtained the AED."
A,S: "No."
At this point, I told them about our idea.
Q: "Do you think that your AED will be at more risk when this solution will be implemented?"
A,D: "I think the real risk will not increase, but it feels like the AED will be very vulnerable, but that is something I will have to get eased to probably."
A,S: "Yes, I think AEDs are very valuable, especially when looking at their cost price. Leaving them open like this must increase the risk."
For Mr. Van Dongen I continued directly to the next question. For Mrs. Smits I briefly explained why we believe the risk will not increase.
Q: "Do you think that giving access to the AED remotely is a good idea from your point of view?"
A,D: "Yes, I do. But I also think that this will not be a smooth transition, I think most owners will not immediately accept this solution."
A,S: "It might be, I am still a bit skeptical. But maybe when the solution has been proven to be effective and the foundations are behind the idea, I can be convinced."
At this point, I thanked them for their time and left my contact info if they had some more comments and/or questions.
What I took away is that both Mr. Van Dongen and Mrs. Smits are hesitant to accept the solution. This doubt can be eliminated by providing our arguments in a digestible way. The owners need a good foundation of arguments.
HartslagNu short interview
In my e-mail to HartslagNu, I tried to get at least some response by asking them directly what they thought of the proposed solution. The person responding to my e-mail, Christel van Huffellen, mentioned that HartslagNu was also looking into the viability of this solution with a third party. This means that they already weighed the pros and cons and came to the conclusion that the pros outweigh the cons. They also believe that the owners of AED's will react positively to this change in their system.
Ilse
New strategy
Since, up to this point, reaching out to relatively big social media pages and asking them to post the survey had yielded no results, I decided to use a more personal approach. I live in a more rural area, with lots of towns close together. Saying that ‘everyone knows everyone’ would be an overstatement, but being able to introduce yourself to someone as a friend or family of so-and-so does make them more inclined to talk to you. First, I asked around my immediate family if anyone knew of someone who was a voluntary first responder or owned an AED. This method was already appearing to be more successful that the social media approach, because I got the contact information to a couple that is heavily involved in the local first aid association, and a former colleague who is an voluntary first responder.
After calling the couple, it turned out that the husband had actually helped install the AEDs in our town and he redirected me to the person who he had installed them with. The wife also knew of someone who was involved in the local AED foundation and provided me with her name. This lead me to Mr. Van der Schaaff and Mrs. Ehlebracht, who are a board member and the secretary of Stichting Polderhart, respectively. Stichting Polderhart manages the AED network in the (former) municipalities Graft-De Rijp and Schermer and nearby towns since 2009. Among other things, they ensure the AEDs are maintained properly, provide reanimation and AED training to citizens, promote the voluntary first responder system and give guest lessons on AEDs to children in primary school. Also noteworthy, not all volunteers of Stichting Polderhart take part in HartslagNu. Instead, when the pincode to the cabinet changes every so often, they are notified by Stichting Polderhart of the new pincode.
The former colleague, Mr. Zwarthoed, is a voluntary first responder from Volendam. All three were happy to be interviewed, and the summaries are provided below.
Interview with Mr. Van der Schaaff
Q: “Are most of the AEDs in a cabinet with or without a pincode?“
A: “Most of them have a pincode. There are a couple of old cabinets that do not have a pincode, but all of the newer ones do.”
Q: “So why did you change from cabinets that don’t need a pincode to ones that do?“
A: “The old cabinets we had were not ideal for outside placement due to poor ventilation. And all the newer cabinets you buy either need a key or a pincode. A pincode is easier because you can send it along with the SMS people receive.”
Q: “Did you ever encounter any vandalism?”
A: “No, we haven’t.”
I then briefly explained our project and asked for his thoughts.
A: “We wouldn’t buy them if they are much more expensive. There is also the problem that if a cabinet is opened remotely, but no one goes to retrieve that specific AED, then that cabinet is just open. Now someone has to actually go there to open the cabinet and retrieve the AED.”
Q: “So you do consider there to be an increased risk if the cabinet were opened longer?”
A: “Yes, I guess. Also, the connection may not work flawlessly, we have never had issues with the current system not working as intended.”
Q: “To your knowledge, have there ever been any issues with opening the cabinets?”
A: “There was one time when someone had remembered an outdated pincode and was unable to open the cabinet. But since people are sent to retrieve multiple AEDs, an AED from another location was retrieved instead.”
Interview with Mrs. Ehlebracht
Q: “Why did you switch from unlocked to locked cabinets?”
A: “After one had been stolen and we wanted to be sure they were secure.”
Q: “One had actually been stolen?”
A: “Not from us, but in Alkmaar*.” (*A bigger city nearby.)
Q: “Did switching to cabinets that are locked with a pincode give you any problems?”
A: “Yes, because some people forget there is an pincode and, in panic, are unable to open the cabinet.”
Q: “Did you ever have any vandalism attempts?”
A: “No, we’ve never had any. We go around the schools to explain to kids about AEDs, what they are far and how to use them and such. I think that helps.”
I then briefly explained our project and asked for her thoughts.
A: “I do believe there are some cabinets that you can have access to via internet, but we don’t have those. They are way too expensive.”
Q: “So are you satisfied with the current pincode system?”
A: “Sort of yes. However, when someone calls 112 because someone needs to be reanimated, I think 112 should have a list with pincodes.”
Q: “Because then they would be able to provide the pincode immediately.”
A: “Yes. Now we have to wait until someone gets a message. I firmly believe this to be a weak point in the system. I have asked HartslagNu if they could change this, but there has been no progress on that front.”
Interview with Mr. Zwarthoed
Q: “For how long have you been a voluntary first responder?”
A: “For as long as the system has existed.”
Q: “Have you had to retrieve an AED often?”
A: “Well, no, because there is one at my front door.”
Q: “And is that cabinet locked?”
A: “No, it is not.”
Q: “Do you know if the other AEDs in Volendam are in locked cabinets or not?”
A: “A few of them are. Those that are privately owned. But all the AEDs that belong to our first aid association are publicly accessible.”
Q: ”Have there ever been any vandalism attempts?”
A: “Yes, twice. One was stolen near a public road, and another was destroyed. But that is since they were deployed, so since 2002.
Q: “So it does not happen often enough to warrant a locked cabinet.”
A: “No, I don’t think so.”
Q: ”Do you know if there have ever been problems opening the privately owned cabinets?”
A: “No, there have never been problems with that.”
Q: “So you are satisfied with how the AEDs are managed in Volendam?”
A: “Yes, absolutely. But I do think more should be unlocked.”
I then briefly explained our project and asked for his thoughts.
A: “Sounds great. What happens now is when a privately owned AED is used, then the battery is refunded by the municipality. It would be great if the added costs would be covered too.”
Short summary
All three interviewees were concerned about the added costs of our idea, stressing the importance of keeping the costs as low as possible. Mr. Zwarthoed firmly believes more cabinets should be unlocked, despite the added risks of vandalism and/or theft. Mrs. Ehlebracht believes bystanders should be able to unlock cabinets as well to reduce the time needed to retrieve an AED. Mr. Van der Schaaff is concerned about the safety of the AEDs if a cabinet were unlocked remotely but no one goes to retrieve it and thus lock it again.
Current cabinet designs
There are a plethora of different cabinets currently in use. For this project, the type of cabinets that are of interest are those in outdoor public places that require a pincode to open. These cabinets do share some functionality, namely they are all ventilated, illuminated and have an alarm. The remaining functionality differences are summarized in the table below.
| Manufacturer | Pyrescom | GT Medicare B.V. | ||||||||
|---|---|---|---|---|---|---|---|---|---|---|
| Cabinet | AIVIA | SmartCase | SixCase | |||||||
| Type | 210 | SC1240 | SC1340 | SC1340P | SC1340M | SC1340PM | SC1440 | SC1440P | SC1440M | SC1440PM |
| Pin | Touchscreen | Rotary knob | Touchscreen | Touchscreen | Touchscreen | Touchscreen | Touchscreen | Touchscreen | Touchscreen | Touchscreen |
| Mechanical lock | - | - | - | - | Yes | Yes | - | - | Yes | Yes |
| Material | PC/ABS | SST | Aluminium | Aluminium | Aluminium | Aluminium | SST | SST | SST | SST |
| Temperature | -20° C | -20° C | -15° C | -25° C | -15° C | -25° C | -15° C | -25° C | -15° C | -25° C |
All three cabinet designs open in a different way. The AIVIA has two horizontally oriented hinges at the bottom left and bottom right corners. The SmartCase is opened like any general locker, with two hinges oriented vertically at the lower and upper right corners. The SixCase has a compartment at the bottom that slides down when the right pincode is entered.
Design options
| Method | Brief description | Functionality needed for the cabinet* | Additional actions needed to function** | Reliability | Maintenance/Risk |
|---|---|---|---|---|---|
| Bluetooth | Anyone with the app can connect to the cabinet via Bluetooth. If a connection is established, the cabinet will open. | -Bluetooth | None | High | All electronics can be equipped inside the cabinet, reducing risk of damage. |
| GPS | GPS is used to determine the user's position relative to the AED. If they are close, the cabinet receives a signal and opens. | -Internet or SMS module | None | High | The current implementation already makes use of GPS. All electronics can be equipped inside the cabinet, reducing risk of damage. |
| Wi-Fi Direct | When the user receives an alert via the app, their phone will start searching for devices to pair with via Wi-Fi Direct. The cabinet will open when a connection has been established. | -Wi-Fi -Other |
The user has to finalize the pairing between the smartphone and the cabinet in some way. Possible options: Bluetooth, NFC, button press. | High, but lower than Bluetooth or GPS due to the additional connection/method needed. | Most/all electronics can be equipped inside the cabinet, reducing risk of damage. |
| SMS | When HartslagNu sends out messages to voluntary first responders in the area, an SMS is also sent to nearby cabinets. Upon receiving this SMS, the cabinets will be unlocked. | -SMS module | None | High | The cabinets will be unlocked early, increasing risk of theft. All electronics can be equipped inside the cabinet, reducing risk of damage. |
| Biometric | Anyone who downloads the app must submit fingerprints/facial picture to a database. The cabinet will open to anyone that matches. | -Internet -Camera or fingerprint scanner |
The user has to pass a biometric lock. | Facial recognition is fallible, especially for people with a darker ethnicity. (Klare, 2012) | A database has to be updated regularly. The exteriors of all cabinets have to be equipped with electronics, increasing risk of damage. |
| NFC | The user transmits the code received through the app via NFC. When installed, each cabinet is given a unique code. | -NFC-tag | The user has to hold their phone to a scanner. | The high stress situation may cause the user's hands to tremble too much. | All cabinets need to be equipped with an NFC tag on the exterior, increasing risk of damage. |
| QR-code | The cabinet has a camera that can read a QR-code generated by the app. Each cabinet that is installed has its own unique code that does not change. | -Camera | The user has to hold their phone to a camera. | May not be reliable in poor lighting conditions. Due to the high stress situation, the user's hands may tremble too much. | Electronics vulnerable to damage have to be installed on the exterior of all cabinets, increasing risk of damage. |
*Assuming the user has a modern smartphone with up-to-date functionality.
**Apart from the user having the app and being in the vicinity.
Selected design
Description
We have chosen to use SMS as a communication tool. The lock will get an SMS module and on receiving an SMS with a specific text e.g. "OPEN", the AED locker will unlock. The Server of HartslagNu, on receiving an alert from the 'Meldkamer' will, in addition to alerting BHVers, send an SMS to the AED locker, unlocking the locker.
Motivation for SMS
We have chosen to use SMS as a way of communication to the AED locker. There are three main reasons we chose this technology. Firstly we know that the server of the meldkamer and hartslagnu already works with SMS. They send an SMS to the Burgerhulpverlener or BHVer to alert him. Secondly, SMS has a high national coverage, practically 100% in urban regions ( https://www.kpn.com/netwerk/dekkingskaart.htm ). This means our system will work everywhere there is a mobile network, which is practically everywhere. Thirdly, this is easier for the users of the app. We do not need to communicate via their mobile phone, which would create an extra point of failure, and more compliance of the Users
Full System
The system would integrate an SMS gateway in the existing webserver of HartslagNu. Since people without the app already get a text instead of an app alert, it is safe to assume a similar system is already in place. Instead of sending this text message to the BHVer only, a seperate text gets sent to the AED box, which houses a microcontroller with a GSM module. This is connected to the internals of the AED box, and can open it once the correct message is received.
Risk scenario analysis
The currently proposed solution might make the AED more vulnerable to thefts, this is because the AED is accessible for a bigger window of time. In this section, the increase of risk will be assessed in order to persuade all users of the importance of the solution.
Numbers of thefts in the current situation
The amount of stolen AEDs is traceable due to the existence of a database for stolen AEDs. This database is for owners of AEDs to report their stolen AED using its unique serial number. The stealing of AEDs is rare according to this database (Gestolenaed, 2019), around five to ten AEDs get stolen each year in the Netherlands. This makes it rare since there are around 100000 AEDs in the Netherlands, making the theft rate around 0,01 percent of AEDs get stolen annually. There are a few reasons why AED theft is uncommon:
1. AEDs contain their own unique serial number, which makes tracking down stolen AEDs much easier (Gestolenaed, 2019).
2. Selling a stolen AED on second-hand websites is not useful since most people prefer to buy a brand new AED (Bos, 2019).
3. The parts that make an AED are not in demand on the second-hand/black market, so trying to sell for the part also does not make sense (Bos, 2019).
4. The language set on an AED is not easy to change, so selling to foreign countries does not make sense (Bos, 2019).
5. Currently, AEDs are well protected by an electronic lock.
The AEDs that do get stolen sometimes do end up abroad but are able to be traced back to the original owner. Vandalism is also a reason why some AEDs get stolen. Not every AED will be found after it has been stolen, so the real reason behind every theft is unknown (Bos, 2019).
Increase of theft risk in the new situation
Risk of theft
In the new situation, AED boxes will be open for a longer period of time, the owners of the AED might see this as an increase of risk on their side. To put the owners at ease, two main points are made why the risk will not increase:
1. Stealing an AED, in general, is not lucrative for criminals. This does not mean the AED can be put outside unprotected. This does however make it viable for a solution where the AED box is open for a bigger time window in the case of an emergency. Assuming an emergency happens every 24 hours and the AED box is remotely opened for 6 minutes, this means that the AED will be accessible 0.42% of the time. The nature of an emergency makes it impossible for a potential criminal to take advantage of this new system since the effort to gain ratio is way too high.
2. Theft usually happens with brute force, where the AED box is being demolished to gain access to the AED. This does not change from the old situation to the new one, so increased theft rates are unlikely to happen due to the current situation.
Due to the current consensus on why AEDs generally do not get stolen, the assumption can be made that the risk will not significantly increase when the new solution will be implemented.
Risks of failure
According to research done by P3 and connect in 2019, the mobile network in the Netherlands is quite good, especially considering down-times. Down-times are time windows where the mobile network is unavailable. The worst provider was down for 17 hours over 9 months, but the provider used by the emergency services, KPN, was only down for 1 hour over 9 months. This makes the risk of failure for the solution considerable. However, the nature of the solution helps in these cases. The solution has always been an addition to the current situation. The pin code used now to open the AED box will not be replaced. This is because, for maintenance reasons, the AED still should be accessible without using a remote-controlled option. This means that the app still can send out the pin code of the AED box in case of a network outage, or software/hardware error. A network outage also causes the emergency number to not be available. In that case, the whole network of burgerhulpverleners will crumble before the chosen solution comes into action. The scope of this project, however, is smaller than solving this more general problem. Due to the nature of the solution being an addition, the risk of failure will not increase with respect to the previous situation.
https://tweakers.net/files/upload/NL%20Benchmark%202019%20V5[1].pdf
Prototype
Due to certain limitations on pricing, scaling and availability of parts, our demonstration prototype will differ from the design in several ways. One such a way is the use of an Arduino Nano inside the box itself. When implemented on a bigger scale, cheaper and smaller microcontrollers should be used to lower the cost take up less space. However, due to the ease of use of an Arduino Nano, its availability, and its large selection of libraries, we shall be using it for the demonstration. Functionality wise, this changing nothing.
Considering the way HartslagNu works, we can assume they have their own server set up somewhere. Adding the SMS functionality with the gateway through an ISP is a viable option because of the scale of the operation and all the information the server already has access to. However, for our demonstrative purposes, we will be setting up a server on a Raspberry Pi with an external SMS module for sending the text messages. This is due to the small scale of our prototype, though the functionality is practically the same. Especially since the Raspberry Pi also has webserver capabilities if we so desire.
By using separate GSM modules instead of the webserver, double the number of SIM cards is required, though only the one used for sending texts needs credit. Because of the scale, which prepaid card is being used is of very little importance as long as the ISP it belongs to covers all corners of the country. Pricing is less of a factor because of this.
Prototype Assembly Process
The prototype can be divided into 3 parts: the Pi with the server and SIM800L module, the Arduino Nano with the other SIM800L module that gets connected to the AED box, and the AED box itself.
The reason a Raspberry Pi was chosen to act as the initiator is because of the relative ease to set up a simple webserver on it. It also has physical serial ports, allowing the SIM module to be directly connected. The server side was set up using the apache framework, creating an IP to which we could send data. The SIM module was connected to the Pi as follows:
The RX and TX pins on the Raspberry Pi are the serial ports that allows the Pi to communicate with the SIM module. This SIM module was chosen for its small size, low price and availability, though it came with a small issue. The GPIO pins on the Pi only output 3.3V or 5V, but the SIM module required anywhere between 3.7V and 4.4V. To deal with this disparity, a diode was added that dropped the 5V down to 4.4V. The capacitor was added to provide more stability. This way, the Pi could power the SIM module directly.
Through the Minicom library for Linux, the Pi would be able to utilize the SIM module. However, some troubles arose when using this library. After being installed on the Debian image on the Pi, Minicom would not take any keyboard input. Only after turning on the local echo did it accept any input. However, no connection could be made the SIM module. After further inspection, the SIM module did not seem to receive any power, with or without the diode. After further testing, including wiring the SIM to an Arduino instead of a Pi to access the direct serial monitor in the Arduino IDE, the SIM module seemed to be malfunctioning indicating a bad unit. Another SIM800L module was acquired and this one did work. Despite the diode and capacitor, the SIM module was still overvolting though it was functioning. After activating the SIM card separately, the module was ready to be connected to. The LED indicator showed that while the module was on, there was no connection to a network.
Initializing...
AT
OK
AT+CSQ
+CSQ: 16,0
OK
AT+CCID
8931080520037043401f
OK
AT+CREG?
+CREG: 0,3
OK
AT+COPS?
+COPS: 0
OK
OVER-VOLTAGE WARNNING
AT+CPIN?
+CPIN: READY
OK AT+COPS=?
+COPS: (2,"KPN MOBILE","NL KPN","20408"),(1,"vodafone","voda
The above monitor output shows some basic diagnostics about the SIM card and module. It shows that a connection was made with the module, it recognizes the SIM card number and shows strong signal strength (20,0). However, the (0,3) implies no connection to a network was made, so we could not send any messages. When checking for networks, the module did find the KPN and Vodafone networks. When tested in an actual phone, the SIM card was able to connect to a network and send a text, excluding this as a problem
Arduino - Sim
For easy prototyping a simple Arduino nano is used. The arduino has the same problem as the raspberry when powering the module. The sim module has a specific voltage that is needed. This is solved by using a diode and small capacitor for stability. However this does not seem to work as is. The SIM module needs a peak amperage of 2A. an arduino nano does not have the capabilities to supply this. so a separate power controll circuit has to be built. For now interfacing with the SIM module is still problematic. Power electronic design is not an easy feat.
Conclusion
Discussion
1. Not all cabinets work in the same way. The main solution should work on every cabinet, however, the exact fitting for every cabinet has not been worked out due to lack of time.
2. The number of responses from users on the survey/interviews is limited. To fully grasp the user response, cooperation with e.g. HartslagNu to reach as many users as possible will be needed. Unfortunately, HartslagNu was not willing to cooperate with us.
3. There is some skepticism from the respondents. An effective way to take away doubt could be by informing the users thoroughly using the arguments made in this project.
4. When re-doing this project, the AED owners should be contacted earlier in the process, since the limited amount of responses could also be explained by a lack of time. It should also not be forgotten that it is quite hard to get responses from AED owners, so a lot of time should be spent on that.
5. It was not transparent at the start of this project that the involved parties are already looking into a similar solution. This could be cleared up faster by contacting the users earlier, however, we found that most foundations are not very willing to cooperate (e.g. HartslagNu). So when continuing this project, a clear visibility on the users is needed.
State of the Art
[1] Cho, H., Ji, J., Chen, Z., Park, H., Lee, W. (2015). Measuring a Distance between Things with Improved Accuracy. Procedia Computer Science, 52, 1083-1088. Retrieved from: https://doi.org/10.1016/j.procs.2015.05.119
A Bluetooth based design for measuring distance between objects using Bluetooth Low-Energy (BLE). The results showed that it is possible to attain an accuracy of 90% in a radius of 1.5 meter.
[2] Drawil, N. M., Amar, H. M., Basir, O. A. (2013). GPS Localization Accuracy Classification: A Context-Based Approach. IEEE Transactions on Intelligent Transportation Systems, 14(1), 262-273. Retrieved from: https://ieeexplore.ieee.org/document/6295661
A study that compares the pros and cons of different GPS localization methods.
[3] Eisenberg, M. S., Horwood, B. T., Cummins, R. O., Reynolds-Haertle, R., & Hearne, T. R. (1990). Cardiac arrest and resuscitation: A tale of 29 cities. Annals of Emergency Medicine, 19(2), 179-186. doi:10.1016/s0196-0644(05)81805-0
Old article at the base of fast-response knowledge investigating the survival rates in 29 different cities depending on the rate and speed of response including which method was used by whom. So option like direct CPR or some time passing before someone with AED arrives. Concludes faster CPR is key to survival but still defibrillation is needed.
[4] Everything you need to know about smart locks. (2021, February 01). Retrieved February 12, 2021, from https://www.safety.com/smart-locks/guide/
Article about safety surrounding smartlocks. This article discussed the opportunities as well as the pros and cons.
[5] H. Oguma, N. Nobata, K. Nawa, T. Mizota and M. Shinagawa, "Passive keyless entry system for long term operation," 2011 IEEE International Symposium on a World of Wireless, Mobile and Multimedia Networks, Lucca, 2011, pp. 1-3, doi: 10.1109/WoWMoM.2011.5986125.
Talks about keyless entry systems of vehicles. Makes use of synchronized keys.
[6] Jeong, H. J., Lee, W., Lim, J., & Hyun, W. (2015). Utilizing a bluetooth remote lock system for a smartphone. Pervasive and Mobile Computing, 24, 150-165. doi:10.1016/j.pmcj.2015.07.010
Talks about a Bluetooth lock and how this should work with an smartphone app. However the phone first has to pair with the smartphone so in this state does not work for multiple unknown devices.
[7] Koster, R. W. (2013). Modern BLS, dispatch and AED concepts. Best practice & research. Clinical anaesthesiology, 27(3), 327–334. Retrieved from: https://doi.org/10.1016/j.bpa.2013.07.005
A study that presents the current strategies for OHCAs. It concludes that AEDs are of critical importance when providing aid, especially before the arrival of an ambulance.
[8] Mair, N., Mahmoud, Q. H. (2012). A collaborative Bluetooth-based approach to localization of mobile devices. 8th International Conference on Collaborative Computing: Networking, Applications and Worksharing (CollaborateCom), 363-371. Retrieved from: https://eudl.eu/doi/10.4108/icst.collaboratecom.2012.250437
Another design based on Bluetooth to determine position. It uses the combined Bluetooth connections of multiple devices. The results also show that, while it is slower than GPS, Bluetooth localization is faster than Wi-Fi or cellular methods.
[9] R. Karani et al., "Implementation and design issues for using Bluetooth low energy in passive keyless entry systems," 2016 IEEE Annual India Conference (INDICON), Bangalore, 2016, pp. 1-6, doi: 10.1109/INDICON.2016.7838978.
Another Bluetooth lock. This one with a focus on low-power Bluetooth. It uses a whitelist for checking which devices may unlock. The white list is controlled by an admin terminal.
[10] Smith, C. M., Lim Choi Keung, S. N., Khan, M. O., Arvanitis, T. N., Fothergill, R., Hartley-Sharpe, C., . . . Perkins, G. D. (2017). Barriers and facilitators to public access defibrillation in out-of-hospital cardiac arrest: A systematic review. European Heart Journal - Quality of Care and Clinical Outcomes, 3(4), 264-273. doi:10.1093/ehjqcco/qcx023
This article explores the different areas which affect the response in assisting in defibrillation and partaking in accessing defibrillators. The study concludes that there is very little evidence in this field and more research should be done into these different factors.
[11] Smith, C. M., Wilson, M. H., & Perkins, G. D. (2018). Reply to: Letter by Derkenne et al. regarding the Article, ‘the use of trained volunteers in the response TO Out-of-hospital cardiac Arrest – The GoodSAM experience.’. Resuscitation, 125, E4. doi:10.1016/j.resuscitation.2018.02.002
The investigation looking at GoodSAM in England, a system somewhat similar to HartslagNu in the Netherlands investigating the acceptance of the system and willingness of people to actually partake in resuscitation including accessing an AED.
[12] Smith, C. M., Wilson, M. H., Ghorbangholi, A., Hartley-Sharpe, C., Gwinnutt, C., Dicker, B., & Perkins, G. D. (2017). The use of trained volunteers in the response to out-of-hospital cardiac arrest – the goodsam experience. Resuscitation, 121, 123-126. doi:10.1016/j.resuscitation.2017.10.020
Article exploring the effectiveness of more participation of ‘bystanders’ in performing in a resuscitation. This participation is achieved via the GoodSAM application which alerts volunteers nearby of a resuscitation request.
[13] Stieglis, R., Zijlstra, J. A., Riedijk, F., Smeekes, M., van der Worp, W. E., & Koster, R. W. (2020). AED and text message responders density in residential areas for rapid response in out-of-hospital cardiac arrest. Resuscitation, 150, 170–177. Retrieved from: https://doi.org/10.1016/j.resuscitation.2020.01.031
A study that shows the effects of increasing the density of AEDs and Text Message responders in residential areas. It concludes that the text message system is most effective when there are at least two AEDs and ten TM-responders per square kilometer. The number of patients who were defibrillated in under 6 minutes doubled when these two conditions were met.
[14] Waar zijn nog AED's Nodig? (2020, September 10). Retrieved February 12, 2021, from https://hartslagnu.nl/aed/waar-in-nederland-zijn-nog-aeds-nodig/
Site with an interactive map showecasing the current spaces where there isn’t an AED in the near vicinity. Based on a history of resuscitation attempts. The rule of thumb here is that there should always be an AED within a 500m radius.
Planning
| Week | Task 1 | Task 2 | Task 3 | Task 4 | Milestones (end of the week) |
|---|---|---|---|---|---|
| Week 1 | Pick subject | Collect information | Make a planning | Update the wiki-page | Subject chosen |
| Week 2 | Work out the different types of connections | Decide on the framework of the app | Electrical design of the lock | Update the wiki-page | Design plan has been made |
| Week 3 | Bill of materials | Work out final design details | Begin working on the code | Update the wiki-page | None/week of progress |
| Week 4 | Make the prototype | Continue working on the app | Make a box for demonstration | Update the wiki-page | App and box are finished |
| Week 5 | Continue making the prototype | Make a test plan and test prototype | Test individual parts | Update the wiki-page | Analysis of the prototype has been done |
| Week 6 | Improving on the prototype | Make final design | Make a test plan and test final design | Update the wiki-page | Final design is finished |
| Week 7 | Begin filming the presentation | Edit the film for demonstration | Update the wiki-page | Film for demonstration is finsihed | |
| Week 8 | Peer review | Last preparations for demonstration | Finalize the wiki-page | Presentation/demonstration |
Work done per week
Week 1
| Name | Total [h] | Break-down |
|---|---|---|
| Mark den Besten | 7 | Meetings [3h], Starting lecture [1h], Research and writing User part [3h] |
| Yann van Eijk | 7 | Meetings [3h], Starting lecture [1h], Research and writing Approach, milestones and deliverables [3h] |
| Ilse Schuckman | 8.5 | Meetings [3h], Starting lecture [1h], Research and writing Problem statements & objectives [4.5h] |
| Rik Schutte | 8 | Meetings [3h], Starting lecture [1h], Research and writing User requirements [4h] |
| Roel Wijnands | 7 | Meetings [3h], Starting lecture [1h], Research and checking references [3h] |
Week 2
| Name | Total [h] | Break-down |
|---|---|---|
| Mark den Besten | 10 | Meetings [4h], Research Design options [3h], Researching SMS API [3h] |
| Yann van Eijk | 10 | Meetings [4h], Rewriting User requirements [2h], Implementing work done in Week 1 on the wiki page [1h], Fixing SotA and References [3h] |
| Ilse Schuckman | 7.5 | Meetings [4h], Research and Design options [3h], updating wiki [0.5h] |
| Rik Schutte | 9 | Meetings [4h], Rewriting User requirements [2h], Research SMS API + Options [3h] |
| Roel Wijnands | Meetings [4h] |
Week 3
| Name | Total [h] | Break-down |
|---|---|---|
| Mark den Besten | 7 | Meetings [4h], Meeting with producer [2h], Selected design [1h] |
| Yann van Eijk | 8 | Meetings [4h], Survey [1.5h], How it currently works [1.5h], Reference searching [1h] |
| Ilse Schuckman | 8 | Meetings [4h], Current cabinet designs [2.5h], Survey [1.5h] |
| Rik Schutte | 9 | Meetings [4h], Creating user scenarios [2h], GSM module + RaPi webserver research [3h] |
| Roel Wijnands | Meetings [4h] |
Week 4
| Name | Total [h] | Break-down |
|---|---|---|
| Mark den Besten | 6 | Meetings [4h], Extra SOTA [2h] |
| Yann van Eijk | 8 | Meetings [4h], researching/writing risk analysis [3h], editing wiki (grammar/spelling) [1h] |
| Ilse Schuckman | 6 | Meetings [4h], Adjust survey [1h], Contacting social media [1h] |
| Rik Schutte | 8 | Meetings [4h], Setup RasPi Webserver [3h], Create Diagrams [1h] |
| Roel Wijnands | Meetings [4h] |
Week 5
| Name | Total [h] | Break-down |
|---|---|---|
| Mark den Besten | ||
| Yann van Eijk | 5 | Meetings [3h], Adjusting risk analysis [2h], |
| Ilse Schuckman | 5 | Meetings [3h], Contacting social media [2h] |
| Rik Schutte | 7 | Meetings [3h], Researching Minicom [2h], Start writing and researching Prototype [2h] |
| Roel Wijnands |
Week 6
| Name | Total [h] | Break-down |
|---|---|---|
| Mark den Besten | ||
| Yann van Eijk | 12.5 | Meetings [3h], Searching for AED owners [2h], Contacting AED owners via e-mail [3h], Interview via phone [1.5h], Adding contact with user part to wiki [2h], Spreading survey via WhatsApp [0.5h], Bullet point list discussion section [0.5h] |
| Ilse Schuckman | 10.5 | Meetings [3h], Asking around for relevant users [1.5h], Research on AED foundations nearby [1h], Mail contact with users [1h], Conducting interviews [2h], Updating wiki [2h] |
| Rik Schutte | 16.5 | Meetings [3h], Acquiring Components [1h], Setting up Debian on Pi with Minicom [2h], Creating physical Prototype (Pi) [2h], Testing and troubleshooting Prototype [7h], Updating wiki [1h], Spreading survey on WhatsApp [0.5h] |
| Roel Wijnands |
Week 7
| Name | Total [h] | Break-down |
|---|---|---|
| Mark den Besten | ||
| Yann van Eijk | ||
| Ilse Schuckman | ||
| Rik Schutte | ||
| Roel Wijnands |
Week 8
| Name | Total [h] | Break-down |
|---|---|---|
| Mark den Besten | ||
| Yann van Eijk | ||
| Ilse Schuckman | ||
| Rik Schutte | ||
| Roel Wijnands |
References
[1] Bhvnederland. (2018, July 27). Yearly 5,300 people die in The Netherlands due to heart attack. Retrieved February 21, 2021, from https://www.bhvnederland.nl/bhv-nieuws/aed-infographic-en
[2] Bos, M. (2019, December 14). Wat kunnen dieven eigenlijk met een gestolen aed? Retrieved March 02, 2021, from https://www.ad.nl/dordrecht/wat-kunnen-dieven-eigenlijk-met-een-gestolen-aed~a3cb6357/
[3] Burgerhulpverlening. (2021, February 18). Retrieved February 21, 2021, from https://nl.wikipedia.org/wiki/Burgerhulpverlening
[4] Dagblad van het Noorden. (2019, October 07). Hartstichting: ,,MEER AEDS nodig om EMMEN hartveilig te maken". Retrieved February 21, 2021, from https://www.dvhn.nl/drenthe/emmen/Hartstichting-Meer-AED%E2%80%99s-nodig-om-Emmen-hartveilig-te-maken-24897372.html
[5] Gestolenaed. (2019, December 18). Retrieved March 02, 2021, from https://gestolenaed.nl/
[6] HartslagNu. (2021, January 21). HartslagNu app. Retrieved February 21, 2021, from https://hartslagnu.nl/burgerhulpverlening/hartslagnu-app/
[7] Jafri, S. (2021, January 30). Rapid defibrillation important for survival: Avive solutions. Retrieved February 21, 2021, from https://avive.life/guides/importance-of-time-to-defibrillation/
[8] Klare, B.F., Burge, M.J., Klontz, J.C., Vorder Bruegge, R.W., Jain, A.K. (2012). Face Recognition Performance: Role of Demographic Information. IEEE Transactions on Information Forensics and Security, vol. 7, no. 6.
[9] Medisol. (n.d.). Onderhoudskosten Van de AED. Retrieved February 21, 2021, from https://www.aedwinkel.nl/onderhoudskosten-aed
[10] Solanki, M. (2017, October 28). Two-thirds of DUTCH ambulance services do not respond within the set time limit. Retrieved February 21, 2021, from https://www.iamexpat.nl/expat-info/dutch-expat-news/two-thirds-dutch-ambulance-services-do-not-respond-within-set-time-limit