Usually, dry cleaning down bags is discouraged. It's thought that the solvents involved will strip the feather's natural oils which are essential to the down's lofting. It's also thought that dry cleaning chemicals will obstruct the breathability of GoreTex-like materials. Finally, there's a concern about those same solvents being retained by the bag leading to some outgassing of some nasty fumes. At the minimum I think you'll find dry cleaning down bags is "generally not recommended." In fact, REI and others say dry cleaning is not appropriate for any bag.

Here's the recommendations that Feathered Friends of Seattle publish;

QUOTE Down bags can, and definitely should, be cleaned when they start to accumulate oils. If your bag has started to lose loft, or the fabric is badly discolored, it is time for the bag to be washed. Body oils, hair oils, lotions and cosmetics are all acidic and will slowly decompose down. Oils also contaminate DryLoft and Gore-tex and heavy contamination may cause delamination. The down in your Feathered Friends sleeping bag was carefully processed to the correct oil/acid balance. We feel that both Down Suds and Thunder Down are the best soaps for restoring down to its optimum oil and acid level after use. An 8 oz. bottle will wash four bags and costs $4.95. It is essentially the same soap used by down processors with some added stain removers. Do not expect either Down Suds or Thunder Down to remove all the stains. DO NOT DRY-CLEAN you sleeping bag. Either wash the bag yourself by carefully following the detailed cleaning instructions below, or have an experienced cleaner WASH your bag using a special down soap. END QUOTE http://www.featheredfriends.com/customer_service/down_feed.aspx#4 There are more detailed instructions at the same url.

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