I am working with a Foundation candidate who has learning difficulties & lives in a house run by a local charity. I visit that house weekly to do the training with him & yesterday (14 August 2019) I was talking with him about EMC. One of the charity's staff overheard our conversation & asked if amateur radio transmissions can interfere with the operation of epilepsy mats. I had never heard of an epilepsy mat & did not get much of an idea as to what they are & what they do. Has anyone come across epilepsy mats, had any experience of how they work & any knowledge of possible interference with their operation from HF transmissions? Thanks.