Concern about radiation from Fitbit trackers

[radiation]

Hi! I was considering buying a fitbit flex and I wanted to know the amount of radiation I was going to be exposed to.  I was wondering if when I turned off the automatic syncing, it would reduce the amount of radiation I was exposed to at all.  Or would the amount remain the same no matter what? 

Moderator edit: Updated title for clarity

[SteveH]

I don't know how much radiation there is from a bluetooth connected fitbit but I do know that you can't turn this off - it's always looking for a device to connect to.

I haven't been able to find anything in the help files that might convince you that it's safe. If it is concerning you then perhaps it's best to not buy one.

[SilviaFitbit]

@radiation A warm welcome to the Community! Just wanted to give you more information about this. The radiation emitted from all Fitbit devices is minimal. It is safe to use your tracker while pregnant.The Fitbit's power output is extremely low: about 0.5% - 1% of the output power of a cell phone.

As for our Bluetooth-enabled devices, a good deal of research has been done in the field of Bluetooth radiation dangers to humans, and the general consensus is that the 800MHz to 2 GHz radiation output of a Bluetooth device is negligible.

Thanks for the advice @SteveH 

[manidemi]

Even though the radiation levels are low, does the fact that you wear it 24/7 increase the risk for unsafe exposure rates? 

[SilviaFitbit]

@manidemi It's nice to see you around! As mentioned in the previous post, there's no risk of wearing your tracker. The radiation emitted from all Fitbit devices is minimal. 

Hope this helps. 

[HappyShireling]

I think my question (I've been reading though a lot of the radiation related threads) is what the BT is actually doing in between syncs.

This is probably more of a "How does bluetooth function" question than a "how does fitbit function" but for me, it's the crux of the issue.

Example: I set my Charge HR to sync manually. I wake up each morning and sync my device - what does the BT do for the rest of the day?

Is it transmitting, looking for other BT devices? Or does it go into a non transmitting listen only mode, waiting to get a sync request from my phone or computer?

EMF is a totally separate question - it's unavoidable with electronic devices. Having BT turned on increases EMF, but I'm honestly more worried about the RF radiation of active BT transmissions.

I know the power output of Fitbits is low, and studies indicate BT is harmless, yadda yadda yadda, but studies and cell phone comparisons aside, I'd feel much more comfortable if I at least knew the BT was broadcasting away 24/7 on my wrist!

Any thoughts?

[SilviaFitbit]

@HappyShireling Welcome to the Community! Thank you for taking the time to read the related threads. 

The Bluetooth will help your tracker to sync automatically without you doing a force sync, in the morning you don't need to do a force sync just leave your Bluetooth always on and it should sync. 

If you don't want to have  your Bluetooth on, then you need to do a force sync. 

Regarding your second question "Is it transmitting, looking for other BT devices? Or does it go into a non transmitting listen only mode, waiting to get a sync request from my phone or computer?" Your Fitbit tracker will sync to your app every time you open it. If you have all-day sync on then your tracker will sync automatically all day. 

You can read more about radiation here. You don't need to be worried about this. Also, you may want to read about the Fitbit app for  Android

Let me know how it goes. 

[Rich_Laue]

To add to the all day Sync, the phone will try to talk to your Fitbit every 60 minutes.

As for RFI on the Fitbit it is low enough that the interferance warning is not required.

[evank]

Hi, I have done a little work with bluetooth modules in embedded devices. I will give you what I understand so far but dont take this a gospel. but here are a few points that could help

1. From other posts I have read it seems the fitbit is always in  "listen" mode which cannot be turned off, this could mean that the device operates as a BLE server. You may need to find out if a BLE server sends packets or transmits RF radiation when not connected. I would take the guess that it does not.

I have also used an application on my mobile that detects BLE transmitters i.e "nRF Master Control Panel" which did not detect any beacons from my fitbit device.

2. Your fitbit will obviously transmit data when synchronizing and during connection to your phone. Accoring to the BLE standard it could either be a Class 1, class 2 or class 3, 100mW, 10mW or 2.5mW respectivly. 100mW being equivelent to WiFi.  Mobile phones on the other hand typically uses 500mW but could go up to 2000mW. I would take a guess that the fitbit is a class 2 device using 10mW. Again this is only transmitting during connection which is a short duration.

My hypothesis is that the only time fitbit emits RF signals is when its connected, hence closing the app (or better yet - disabling bluetooth on your phone) ensures the fitbit will never transmitt RF signals (until you re-enable bluetooth on you phone) also I have seen that after syncing the fitbit remains connected for 15 minutes.

[Rich_Laue]

@evank that's true your fitbit is normally in a listening state.. What it is listening for are requests from a BTLE server., your fitbit is a receiver. The phone or PC is the server. 

Fitbit being a receiver can only connect to a single BT server at a time, and is unable to initiate a connection.. It is only able to respond to connection requests, which will not happen until approved by you.. Of course the only thing that can request a connection to your tracker is a fitbit app, u. G. J

It would be easy to find out what signals are needed to keep the units bonded. I haven't looked into it.

What I have looked into is the signal. It is an extremly low power device, the packers are very small compared to regular bT.

[Rich_Laue]

@evank that's true your fitbit is normally in a listening state.. What it is listening for are requests from a BTLE server., your fitbit is a receiver. The phone or PC is the server. 

Fitbit being a receiver can only connect to a single BT server at a time, and is unable to initiate a connection.. It is only able to respond to connection requests, which will not happen until approved by you.. Of course the only thing that can request a connection to your tracker is a fitbit app, u. G. J

It would be easy to find out what signals are needed to keep the units bonded. I haven't looked into it.

What I have looked into is the signal. It is an extremly low power device, the transmission packets are extremely short compared to regular bT.

[Book313]

I know the last reply was since August of 2016. I. Am wondering if you have bought a Fitbit yet. And if so, what convinced you to get one (regarding to radiation). There have been tons of arguments, some explaining that the RF is low in Fitbit. While others still contemplate as no substatial evidence has been provided yet to back up the claim, that Fitbit and other wearable devices could/don't cause 'problehms?' Not necessarily 'problems' , but alarming effects you could say. ( Making sense? ) I am also wondering, if you do, what 'evidence you have to support that Fitbit and other wearable devices could/could not be 'dangerous'.

Thank you as I know that was kinda long! Thanks again!

[Rich_Laue]

WHat kind of radiation are you concearned about? RFI or EMF.

Turning a light bulb on, cell phone in your pocket, the tower, a computer, and car (a lot here)  all give off both. The wireing in your house, hair dryer, or toaster, and the lines by the roads also give off EMF,  

Just saying that there is s lot more things to be concearned about then the slight radiation from your fitbit. For the most part signal strength has a lot to do with RFI and current affects EMF. , which cant be much since the small battery lasts me 6 days.

[SantiR]

@Book313 Thanks for joining the Fitbit Community! That's a good questions. I believe it is not dangerous at all because the research I made led me to this great post from @MarlenS which clarifies the reasons why it is not dangerous to wear!

I also found this thread... it is worth checking the posts within it! 

@Rich_Laue Thanks for your awesome help and for sharing your valuable experience! 

See you around! 

[lilleesup]

What is BT? My girlfriend and I both wear fitbits and I was wondering about Emf. Told her I would do some research. Especially since they are saying cell phones are causing brain tumors. The cases of brain tumors and cancer are rising at tremendous rates. I can't even tell you how many people I know that have brain tumors that are cancerous. 

[Rich_Laue]

BT stands for Bluetooth, it is a short range <30 feet, communication. It falls within the WiFi band.. 

As for the Fitbit Bluetooth is always listening, like any desktop radio will, and only transmits for a second when requested to do so. 

As for cell phones, who are they? Science has not been able to prove or disapprove this. The cell phone is in a different class, not trying to talk to a device in the same room, but a tower that could be a few miles away. 

[Book313]

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@Rich_Laue wrote:

WHat kind of radiation are you concearned about? RFI or EMF.

Turning a light bulb on, cell phone in your pocket, the tower, a computer, and car (a lot here)  all give off both. The wireing in your house, hair dryer, or toaster, and the lines by the roads also give off EMF,  

Just saying that there is s lot more things to be concearned about then the slight radiation from your fitbit. For the most part signal strength has a lot to do with RFI and current affects EMF. , which cant be much since the small battery lasts me 6 days.

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I'm concerned about both types of radiation. And I know that my surroundings can be sending off radiation in larger amounts, but having a device on my arm 24/7 transmitting whatever and giving off RF is very concerning for me.

An additional question I have is, that may be erelavent to these threads... Would logging out of my Fitbit account on the Fitbit app disconnect or limit the RF from the 2 devices, (Fitbit and the device used to sync)???

[WendyB]

Do you Know that your cell phone gives of more radiation then  any other device???

[Book313]

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@WendyB wrote:

Do you Know that your cell phone gives of more radiation then  any other device???

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She's correct. But I'm sure that sooner or later there will be more devices that transmit more radiation.

[Fudgecake]

Hello, please could you tell me what the Bluetooth power output is in mW of Fitbit devices in general? 

Also, are there any known issues regarding Radio Frequency Interference (RFI) and the use of Fitbit devices?