I designed these modifications to reduce fumes and particles when printing ABS/ASA and other materials. It's working great.
The activated carbon filter requires some modification to the original housing/duct but I reckon that using carbon pellets is better than the carbon bags QIDI sells.
You will need longer screws for the Hepa filter Holder.
The HEPA filter model is the H11 made for Samsung vacuums.
(https://www.aliexpress.com/item/32886698848.html?spm=a2g0o.order_list.order_list_main.5.4650caa4fSZK8s&gatewayAdapt=glo2bra)
The author marked this model as their own original creation.