UK fly deterrents

We live near a river and suffer with lots of small black fly’s swarming the area, ala last night, when we tried to sit outside (previous years have had us vaccuming the wall/ceiling). They’re annoying but not particualy bity, so any suggests for deterring them? Been being spammed lately about the Thermacell Halo Mini Patio Shield, and youtube reviews suggest it does work on mosquitos but not necessarily regular flies.

PS: Trying to avoid covering ourselves in DEET

If they are very small than a simple desk fan blowing across you will keep them away.

How about something to attract them away from where you are sitting ?.
Make up a jar of watery jam and leave it sitting open. Hopefully they’ll all be buzzing around that instead of you.

That works with wasps, not so sure these will be interest. G/f said why not just get citronella candles.. so I bought the Thermacall… gunna give it a go & send it back if it doesn’t help.

Thermacell has worked for me as long as it is still. As far as I understand it, it is mainly chrysanthemum oil.

Red Top fly catchers work really, really, well… but they do stink of rotting stuff, so they need to be hung far away from where you are.

I have more trouble with them inside the house; this year I’ve bitten the bullet and bought a chain curtain for the back door and it seems to be working well, we’ve only had a couple of flies in the last 2 weeks rather than 3/4/5 at any given moment.