Legal Question in Landlord & Tenant Law in Ohio

In Ohio, R.C. 5321.04 requires that the landlord put and keep the premises in a fit and habitable condition. This means that if there is an insect infestation that is not the fault of the tenant, then the landlord must pay to correct the problem. Since the landlord is spraying the whole building, then I don't think that all of the tenants would have to pay for the spraying since, even if one of them caused the problem, then it should be that tenant who should have to pay for the whole thing. But absent evidence of which tenant, if any, caused the problem, I think that the landlord would have to pay for that.