Sawdust
Sawdust particles are so fine that they can cause respiratory issues for all poultry. The fine dust is also difficult to remove from the coop entirely, so it can also pose a risk to human health. Rule out adding sawdust to either the floor or the nesting boxes.
The wind is also likely to move sawdust around and cause eye problems.
Chicks in the brooder also should not be put on sawdust, not only because they could breath it in, but chicks will EAT sawdust and fill up on that instead of nutritious food. Chicks should be limited to chick crumble and a small amount of fine shellgrit.
Rule out using Sawdust.
Wood Shavings
While it is still soft, the packaged product from reputable sellers is also dust extracted to reduce dust participles. This will help in keeping down occurrences of respiratory and eye conditions that we associate with sawdust.
There are varying grades of wood shavings amongst brands. The larger is less likely to be eaten by chicks in the brooder while still giving absorbency.
Wood shavings do not blow around as much as sawdust but can still be blown out of the coop.
Using wood shavings in the nesting boxes is ideal.
It helps reduce places for lice and mites to hide, as well, compared to whole straw which are hollow and a great place for them to hang out, undetected.
Using either wood shavings or chopped straw as nesting box material are excellent choices.
Wood shavings can go directly into your compost heap or in the greens bin for easy removal.
When cleaning out from under their roosting area, not all wood shavings need to be cleaned out every time, just scoop out the dropping with a little of the shavings. So simple.
Wood Chips
When the poultry run becomes very muddy when wet, wood chips are a great choice to help bulk out the soil to reduce the slipperiness.
Combining wood chips with some logs throughout the yard make a great way for the chickens to avoid being on a wet sodden ground over a prolonged period of wet weather, which they need to stay healthy.
The chips are too large for poultry to attempt to eat, usually.
And occasionally you may find eggs laid on it while they are warm and dry.
But do not be tempted to use wood chips as a nesting box material. The chips may prove to be quite abrasive on the egg shells which will cause them to crack, which in turn can encourage egg eating amongst the hens.
What about as a coop flooring?
It works well in the run because the run also has a chance to dry out in the sun, unlike some coops.
It will depend on your coop set-up but it would not be advisable for the small pet shop type of coop.
Wood chips must NOT be made from TREATED PINE as this chemical is not good for animals. So source wood chips from a reputable seller.