If you find active woodworm in the museum

Signs of beetles or fresh frass (insect droppings) coming from holes in wooden items even though they have been moved recently or fresh looking holes (light colour inside). This guidance is for treating simple wooden items which may have a small amount of metal or leather. It is not suitable for items with ivory or glass or other materials – isolate them as described below, then check with a conservator before treating.

  1. Photograph and document each stage thoroughly.
  1. Prepare a suitable work area and have layers of acid-free tissue on the work-surface so you can see and capture any loose fragments or insects. Have small ziplock bags to put them in and labels (e.g. pieces of paper and a pencil) to enclose with them. Don't rely on writing on the bags - it doesn't last. Assemble all the tools and materials you need including polythene sheeting, parcel tape and acid-free tissue.
  1. Make sure you have suitable personal protective equipment and means of disposal of any debris especially if the old packing materials are contaminated with pests as well.
  1. Get everything up off the floor and vacuum, including vacuuming all shelves. Often woodworm beetles emerge from the underside of wooden crates and create a happy living area between the object and the floor, so examine the underside of any wood or card boxes and vacuum. Use a vacuum with a HEPA filter and empty it after each use.
  1. Isolate anything that looks as though it has fresh woodworm holes and plan to treat it ASAP but at least before March/April when adults may emerge. If it has metal parts or may have been damp, place it on a pad of acid-free tissue in the polythene bag to help buffer changes of moisture, prevent condensation. Make sure the bag is strong and well-sealed. Items that are delicate or decorated etc can be wrapped in acid-free tissue, then sealed airtight in polythene. If the item is in a box you can wrap the box in polythene.
  1. Seal ALL the edges of the polythene with brown parcel tape (the plastic sort). Don’t just fold over the polythene and apply a strip of tape, you must run tape all the way along all the edges so that the package is airtight. This helps prevent freezer burn while the object is in the freezer and condensation when the object comes out.
  1. Place the sealed object in a freezer until you are sure it is frozen all the way through. This can take a week. If the freezer is a commercial one and reaches -26'C consistently you only need to freeze it once. If it is a domestic freezer, and only reaches -20'C you need to freeze it for at least a week, gently lift it out (remember the object may be very brittle while frozen, so support it on a tray or card if it is fragile), let it thaw, still sealed, for a week and then freeze it again for at least a further week. This will kill the adults and larvae on the first freeze, trigger the eggs to start developing and kill them on the second freeze.
  1. After freezing is complete, allow the object to defrost for several days before opening the package. Do not open the polythene until the item has finished thawing right through. Only open the package when you have a clean area to put the object back in. Gently examine the object, picking off any insects or debris with a pair of tweezers and an artist's paintbrush (soft, watercolour type, not bristle).
  1. If the item is too large to fit in a freezer, objects which are plain wood can be treated by injecting woodworm treatment into ALL the flight holes, then putting it in a plastic bag or polythene box for a few days to allow fumes to permeate the object. Follow the manufacturer’s instructions carefully. Wear gloves and work in a well-ventilated area. Wear goggles if there's a risk of splashing liquid. Dispose of waste carefully. Use soft, white paper towel to wipe excess fluid off surface straight away. Larger items can be stood on a polythene sheet during treatment. The polythene can be wrapped over them afterwards for a few days. Take care not to leave polythene in contact with the freshly treated surface – have a layer of acid-free tissue in between. Varnished or painted surfaces can be affected by the solvent in the treatment so may not be suitable for this kind of treatment. If in any doubt, please ask a conservator.
  1. Put lots of blunder pest traps in the area and monitor them every couple of weeks until you are sure there is no other live infestation in the area. Then continue to monitor every month from Feb – June and every 2 months for the rest of the year. Remember pest traps are just a way of monitoring the area, they do not catch ALL the pests.

And finally - don't panic! Well done for spotting the problem. Cleanliness is your best aid, so lots of vacuuming and disturbing any little blighters in the area in future.

Conservation Development Officer

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