In dotnet, if I create a (HashSet<T> disposable) where T : IDisposable and store the hashSet object in a field. When the Disposable objects will be disposed? Consider this code:

    public class LongRunningProcess: ServiceBase 
    {
        private HashSet<IDisposable> set;

        public LongRunningProcess()
        {
            set = new HashSet<IDisposable>();
        }
        void Process()
        {
            using (var disposable= new IDisposable() )
            {
                if (!set.Contains(disposable))
                    //Process
                else
                    set.Add(disposable);
            }
        }
    }

In this code I have created a class that holds onto the HashSet field, because it is a worker service it never dies (until next restart). Does that imply that the hashset’s members will be disposed of at restart? Considering that hashsets are a set of hashes does their lifespan affects the lifespan of their member object?