To hydrate the sensor felts you’ll need:

• a glass; and
• saline solution.

Then follow these steps:

1. Place the sensor felts into a glass and then soak them with saline solution.
2. When they are fully hydrated, squeeze each one gently to remove any excess fluid.
3. Fit the hydrated sensor felts into the sensor locations on the Flex Cap.

Saline sensors can dry out while you’re fitting the Flex Cap to your participant’s head. This is due to absorption from your participant’s hair and scalp. To ensure the best contact quality during your recording session, please follow these steps.

When the Flex Cap is fitted to your participant’s head, and you’re ready to start recording, you must do the following:

1. Open the contact quality map in PRO and ensure that your Flex is connected.
2. The contact quality map will show you the contact quality for each sensor. Each sensor should show as green on the contact quality map. Starting with the references DRL/CMS, top-up sensors with saline solution (as required) until each sensor turns green. The contact quality should be 100% and green on all channels.

If the sensor felts dry out during your recording session or you have a long recording session, you can re-hydrate them through the hole at the top of the sensor.

When you see the contact quality change from green to orange in PRO, it’s time to top-up the saline solution.

To hydrate the gel sensors, you’ll need:

• isopropyl alcohol;
• cotton buds;
• abrasive gel (optional);
• electrolyte gel; and
• a syringe with a blunt needle.

When the Flex Cap is fitted to your participant’s head, and you’re ready to start recording, you must do the following:

1. Open the contact quality map in EmotivPRO and ensure your EPOC Flex is connected.
2. To prepare your participant’s skin for the gel sensors and to minimize skin contact impedance, use a cotton bud to move your participant’s hair away from the sensor opening so it can make good contact with the scalp.
3. Clean the skin below the sensor opening with a degreasing agent, such as isopropyl alcohol. To do this, dip a cotton bud into isopropyl alcohol, then degrease the skin by rotating the cotton bud inside the sensor opening.
4. This is an optional step but doing it will improve contact quality. Dip another cotton bud into the abrasive gel, then gently rotate on the skin so that it abrades the skin in that sensor location. Take care not to rub the skin too hard.
5. Once you’ve cleaned and abraded your participant’s skin, you then need to fill a syringe with electrolyte gel. When you’ve filled the syringe with electrolyte gel, insert the syringe tip into the sensor opening and fill the gap between the scalp and sensor completely with electrolyte gel. Start by filling the CMS and DRL sensors with electrolyte gel first. You should see the contact quality map in EmotivPRO turn green for these sensors.

Repeat steps 2-5 for each sensor placement. Once you’ve prepared each sensor, check the contact quality in EmotivPRO. The contact quality should be 100% and green on all channels.