Earthquake Securing: Frequently Asked Questions
Although I’ve been focusing lately on social media in disasters, response, recovery, CERT, ham radio, LTRGs, VOAD, VOST and such, my area of expertise that led me towards all of this in the first place was my work performing earthquake securing of art and objects.
I did that for over 10 years at The J. Paul Getty Museum in Malibu, then had my own earthquake securing company in L.A. for close to 10 more. I’ve always loved that work (and still do it on occasion, as I am now for a special project at the Architectural Heritage Center in Portland, OR), but our move to a small town far away from large art collections and museums made it difficult for me to do this work.
But this is still very useful info, and since my biz website is long gone, this seems like as good a place as any to offer this information to the public.
So here’s a “Frequently Asked Questions” post to get things started. I’m be happy to discuss this here, or twitter or facebook, or via email if you like. Enjoy, and I hope people find it useful.
Earthquakes and Objects: Frequently Asked Questions
On securing furniture and objects to walls:
Q: Is it true that securing furniture/objects to walls with flexible fasteners (such as heavy nylon strap or steel cable) allows some “shock reduction”?
A: No. This would be true if the furniture were on a seismic isolator which allows movement in all directions, but this is not possible when an object is against or near a wall. In these cases, a rigid fastening system is best. Flexible systems allow the furniture to “rattle” back and forth between the wall and the end of the tether, increasing the amount of force transmitted into the furniture. This also increases the chance of damage to anything that may have been secured to the furniture itself.
On the proper use of non-skid materials:
Q: Can objects be kept from toppling or sliding off a surface by putting non-skid material underneath?
A: Non-skid materials will only help prevent sliding and toppling if the object in question is completely stable and bottom-heavy. Otherwise, the non-skid actually “trips” the object, causing it to topple even faster than it would if it could slide around.
On the use of waxes, puttys, velcro and adhesives:
(Warning: These adhesive-type products only work if an object is a very stable shape, in good condition, and has a suitable surface for adhesion. A physical restraint made of metal, acrylic, or composite materials is stronger and safer when the stability or condition of an object is questionable. If the object you wish to secure is valuable or fragile, consult a professional.)
Q: Since some materials can cause irreversible damage to sensitive art objects, what are the safest materials to use?
A: The following are recommended guidelines for use of adhesive type materials on works of art:
• Wax is the safest adhesive-type material to use to secure sensitive objects to sensitive surfaces. It is least likely to cause damage, although there is still some risk of damage if improperly used or removed. Some of the commercially available “Museum” waxes are very soft, and will only work for very light weight, stable objects.
• Puttys vary somewhat in chemical makeup, but most have sulphur in them, and they all (in my experience) leave an oily residue on porous surfaces when left for a long period of time. (I have even seen some puttys dry up and become “gummy”, to the point that they could not be easily removed, and stained some objects.) It sticks very well, but due to the problems mentioned above, it is not recommended.
• Clear Gels do not stay in place. They liquify and run out from under the object, leaving a mess, and not always leaving enough gel to actually hold an object. I have seen (and have pictures of) objects that moved several inches on a shelf that was not level.
• When you secure an object with velcro, you are actually securing the velcro with an adhesive that is attached to the velcro. This should not be used for art or sensitive objects, as it might remove some of the objects surface when it is removed. Likewise, velcro or double stick tape should not be used to secure objects to walls, as it is likely to fail by pulling off the top layer of paint or wallpaper.
Q: I have heard this type of work referred to as “earthquake proofing”; can I be certain nothing will be damaged?
A: NO. The reason that the securing of objects is referred to as “earthquake damage mitigation” instead of “earthquake proofing” is because the best that can be done is to decrease the risk of damage, not eliminate it. Due to the completely unpredictable nature of earthquakes, there is no guarantee that objects will survive undamaged. However, earthquake damage mitigation can significantly increase the likelihood of an objects survival, especially for objects of unstable shape. The value of earthquake securing of objects and furniture has been proven many times over by Loma Prieta(1989), Northridge(1994) and many other earthquakes.
Update: For those who want more background on this subject, here’s a paper that I wrote on earthquake securing for museums. It is more restrictive on the use of certain materials like waxes and putties than one needs to be in the average household, but it provides a good introduction to earthquake securing concepts. -sr