What are inspection cycle and method for the appearance of immersion oil in immersion cooling miners?

Do you recommend using miners at higher frequencies, or do you consider this too risky for miner's lifespan?

What is the limit on particle size in immersion oil of immersion cooling miners?

How to determine sampling points of immersion oil in immersion cooling miners?

Which immersion oil is recommended for immersion cooling miners, and what is the dosage standard?