There is nothing harmful in unsealed timber as long as it has been dried, apart from the possibility of splinters from rough surfaces. Some timbers might cause a skin allergy when 'green', but the items you mention are unlikely to be from freshly cut logs. However, raw timber can become grubby with handling and will be more difficult to keep clean in the long term, so you might consider sealing items that will be handled regularly and/or be subject to food and drink spillage, such as table tops and possibly climbing frames.Play equipment
Answered on 16-09-2020
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