Any modifications including in-cage barriers should have been passed as safe for purpose by the manufacturer of the MEWP. We do not personally run any such modifications in our current fleet, though protective equipment is often supplied by customers where they have identified it as necessary for a job.
Every job is different, e.g. depending on the specific machine (the size/capacity of the cage, etc) and the size/weight of equipment such as a chainsaw to be used.
For example if you identify the risk in your 'risk and method statement', and include rules for safe distances between the operator and worker to be maintained whilst work is carried out, then this may be sufficient if you are deemed to have taken necessary care. I would not attempt chainsaw work in a machine with a small cage.
