This comes from our friends at CRESA:
This morning, an estimated 866,000 people in Washington State participated in the Great Washington Shakeout, a statewide 'drop, cover, and hold on' drill. The reason why we 'drop, cover and hold on' when the ground shakes is to protect ourselves from what in the building trades they call 'nonstructural' items.
Most injuries in earthquakes occur when these items come crashing down on victims: computers, monitors, tall furniture, TVs, appliances, ceiling tiles, light fixtures, bricks, tiles, etc.
Put simply, nonstructural items are anything in a building that's not dedicated to keeping a building upright. This also includes cladding, mechanical systems, electrical systems, piping, HVAC, fire protection systems, and so on. Since the early 70's in the US, building codes required that buildings be built to withstand some level of ground shaking.
However, for the most part, these codes only address structural components. They do not fully address nonstructural components. So for the building you are in, unless there was special attention paid to securing nonstructural items, they may fail in an earthquake. If they don't fall and hurt someone, they may still block exit routes.
They may also be damaged to the extent that the building is unusable. Nonstructural items represent the majority of the costs of a building and so damage to these items can be very expensive and can extend the time it takes you to recover.
The good news is that it's fairly easy and inexpensive to secure nonstructural items. There are a number of strategies but probably the best two are a) relocation and b) anchoring. Relocate especially dangerous, loose items to a place where they don't crash into people or into other items or block exit routes. For items that can't be relocated, anchor them to a secure point such as wall studs.
Here are some other tips: Do a walk through of your home and workplace. Inventory and prioritize high risk items and come up with a plan to mitigate them. This is a great project for a work safety committee. Secure your hot water heater. Kits are available at hardware stores. Demand seismic design for any new construction, remodeling, installation, and retrofits Easy and essential items to secure at the home or office are computers, office equipment, and tall furniture. Simple L-brackets and velcro can do the trick. Specific fasteners are also available. Do a web search for "earthquake fastening solutions".