Frequently Asked Questions

Detecting seizures

What kinds of seizures does NightWatch detect?

NightWatch detects the majority of clinically urgent epileptic seizures, including tonic-clonic seizures, tonic seizures lasting longer than 30 seconds, hypermotor seizures, and myoclonic seizures.

How does NightWatch detect a seizure?

NightWatch starts working when the wearer is in bed with the arm module. NightWatch then automatically adjusts to the resting heart rate of the wearer. NightWatch will alert you if it measures certain sudden deviations from the resting heart rate while the wearer is in bed.
Movement patterns are also carefully monitored. Advanced algorithms identify shaking/vibrating movements as a possible epileptic seizure. There are several movement and heart rate algorithms that individually alert you to a possible epileptic seizure. NightWatch will also alert you if the system measures an extremely low heart rate.

What happens when NightWatch detects a seizure?

In the event that NightWatch detects a possible seizure, this is passed on to the corresponding base station, which emits an alarm signal and possibly forwards the alarm to a suitable care call system.

Alerts and range of NightWatch

What is the range between the arm module and the base station

The range between the transmitter and receiver depends on the construction of the house. The range is about 80 meters in an open field but in a building usually about 10-20 meters (in a straight line). We experience the least reach in houses with reinforced concrete. The strength of the signal decreases slightly when the wearer puts on the arm module or covers it with their body. NightWatch will sound a technical alert (two beeps, repeatedly) if the connection between the arm module and the base station becomes too weak.

Is NightWatch able to alert caregivers beyond the range of the wireless signal?

The NightWatch base station can be freely connected to any existing care call system. If this is not available, LivAssured can provide an optional GSM-module that can transmit an alarm signal via a GSM call to one or more telephones.

Will the alarm automatically stop?

Yes, after three minutes, the alarm will automatically stop and the detection function will switch on again automatically.

What happens if NightWatch is out of range?

If the NightWatch is out of reach of the base station, an alert signal will sound (2 beeps, every 2 seconds).

Using NightWatch

From what age can NightWatch be worn?

NightWatch is most suitable for people with untreatable epilepsy from the age of four. Under the age of 4, there is an increased risk of false alarms or undetected seizures. This varies from person to person.

Is NightWatch comfortable for everyone to wear?

NightWatch consists of a comfortable armband worn around the upper arm during the night. The armband just needs to be adjusted to size once and can then be slid onto the arm; even small children can do that themselves. Once it is in place, most users do not feel any discomfort at all.

How long does the arm module battery last?

A fully charged NightWatch arm module will work for at least 13 hours. After use, reconnect the NightWatch arm module to the charger immediately. This will automatically turn off NightWatch and it will recharge. The arm module is protected against overcharging so it can safely be left in the charger. If NightWatch is not always connected to the charger immediately after use and runs out, it will shorten the battery life significantly. If the NightWatch battery runs out, a warning signal will sound (4 beeps every 2 seconds). If this keeps happening, please contact us. See also the NightWatch notification card for the different notifications and alerts that NightWatch provides and what they mean.

Does it matter how the arm module is worn?

NightWatch should be worn directly on the skin, preferably on the front of the upper arm (biceps). There is no top or bottom to the NightWatch, just a front and back.

Why is NightWatch specifically designed for night-time detection?

Because NightWatch is optimized to detect nocturnal seizures, NightWatch does this accurately for many people. Systems that work day and night are often less sensitive because they have to distinguish between a seizure and daily activities, such as walking around / playing / brushing your teeth, etc. NightWatch does not have to do this. NightWatch can be put on before someone goes to bed, but will only start measuring very accurately when the wearer is quietly in bed.

How long is the warranty on my NightWatch?

Your NightWatch is guaranteed against defects caused by normal use for two years from the first time you use it. If anything is wrong with your NightWatch, please contact us.

Can you connect multiple arm modules to one base station?

It is not possible to link multiple arm modules to one base station. The arm module and base station always work in unique pairs.

Can you connect multiple base stations to one arm module?

It is not possible to link multiple base stations to one arm module. An arm module can only have one unique link with one base station.

The NightWatch Portal

What is the NightWatch Portal?

If your base station is connected to the internet during use, the measured heart rate and movement data and any NightWatch notifications will be sent sent to the NightWatch Portal. You can then read out these data at a later date via the website
This provides insight into how the armband wearer’s night went and helps you to better understand why NightWatch gave any notifications. You can also use the portal to map and compare any epileptic seizures measured. It can be interesting to share the data with your neurologist, especially in the case of medication changes.

My NightWatch no longer shows any data on the Portal, what's the matter?

Check that two orange lights on your base station are lit equally bright. If the second light does not glow orange, your base station is not properly connected to the internet. Check your internet connection. Your base station must remain connected to the internet while using NightWatch in order to transfer the data.

Do I need an internet connection for my NightWatch to detect seizures?

No, NightWatch is a stand-alone alarm system that does not require an internet connection to detect seizures. A continuous internet connection is only necessary to be able to view the measurement data online.


My NightWatch sometimes gives an alert when there is no seizure. What's the matter?

It is important to understand the NightWatch alerts. Refer to the notification card in the user instructions for this. A distinction is made here between technical alerts and epilepsy alerts.

Technical alarms

Battery (nearly) empty:
If your NightWatch gives this message during the evening, it had not fully charged during the day. Make sure the NightWatch arm module is switched on and is always connected to the charger during the day.

Out of range:
If your NightWatch gives this message during the night, this could be because the wearer is lying on top of the arm the NightWatch arm module is on, for example, which would make it difficult for NightWatch to reach the base station. This problem can often be solved by placing the base station closer to the wearer’s bedroom. If this means that the alarm can no longer be heard, an optional GSM call module can be linked to NightWatch. The out-of-range alert could also indicate that the arm module has accidentally been switched off. Check that the arm module is turned on.

No heart rate detected:
If this alert occurs during the night, it means that the sensor (green lights) under the arm module cannot read the heart rate properly. Check that the arm module is in contact with the skin of the upper arm and has not slipped off or been taken off.

Epilepsy alarms

NightWatch may give an alert if the wearer makes certain movements that resemble an epileptic seizure, such as scratching, or if the heart rate suddenly increases sharply. The likelihood of false alarms increases if the wearer sleeps restlessly. NightWatch may also alert you to minor seizures that have already passed before you get to the wearer, and which may therefore appear to be a false alarm.

If false alarms occur too often, please contact our helpdesk.

My NightWatch sometimes fails to give an alarm in the event of a seizure. What's the matter?

NightWatch has been developed to detect severe epileptic seizures, where assistance may be required, as accurately as possible. NightWatch can also miss seizures, however. Very small seizures or seizures that do not involve a change in heart rate or movement are usually not detected. Severe seizures may also not be identified by NightWatch as possible seizures, despite strong movement by the wearer and a high heart rate. The NightWatch portal can provide more insight into why this is the case. Seizures may be missed if the wearer sits upright shortly before a seizure, for example. In these cases, we recommend wearing the NightWatch arm module on the lower leg, e.g. the calf.

If NightWatch misses major seizures, please contact our helpdesk

Does the wearer's position in bed affect the working of NightWatch?

If the armband wearer sleeps in a horizontal position, NightWatch will detect possible seizures. So, it doesn’t matter whether the wearer lies on their back, stomach, or side.

I see that there is only one green lit on the underside of my NightWatch arm module. Is a green heart rate light defective?

NightWatch automatically switches between one and two lights, depending on how much light the sensor receives. You can test that both lights are working properly by removing the arm module from the charger when it is on, at which point both lights will illuminate.

I can see a rash where the arm module has been, what can I do?

Some people may develop a red area or rash after wearing a device that presses against the skin. This will often not bother them and go away by itself. If it does become a problem, a special soft plaster is available which can be stuck to the arm module.

The base station keeps emitting 2 beeps every two seconds even though the arm module is switched on and within 3 meters from it.

It can happen that due to a connectivity issue the NightWatch arm module loses connection with the base station. It doesn’t happen often but when it happens the base station emits two beeps every 2 seconds and you will see a (weak) red flashing light or a continuous (weak) orange light in the dent on the white side of the arm module. Is this still happening when the arm module is within 3 meters from the base station? Then you have to reconnect the arm module to the base station. This can be done easily using the following instructions.

When you see a continuous (weak) orange light on the arm module:

– Make sure the base station is plugged in.
– Take the arm module of the charger.
– Press and hold both volume buttons of the base station for 15 seconds (the two little bumps on top of the base station).
– Reconnect the arm module to the charger.
– The base station should have stopped beeping and two green lights should be lit indicating that it has found the arm module.

When there’s a (barely visible) flashing red light on the arm module:

– Make sure the base station is plugged in.
– Remove the arm module from the charger.
– Use a pen to switch the arm module off and then back on.
– Throw the arm module 3x at least 1.5 meters into the air and catch it to bring it into pairing mode.
– The dim light on the white side of the arm module should now be continuously orange instead of flashing red.
– Press and hold both volume buttons of the base station for 15 seconds (the two little bumps on top of the base station).
– Reconnect the arm module to the charger.
– The base station should have stopped beeping and you should see two green lights showing you that it has reconnected to the arm module.