Unlike most people on the West Coast - who only think about earthquakes when they absolutely must - when Tim Claydon feels the earth move, he's hard at work for the Pacific Geosciences Centre. He designs and builds devices that attach to earthquake sensors and turn the data into a form that can be sent by radio.

Earthquakes happen about five times a day in British Columbia. Many significant quakes occur in unpopulated areas, where there is no one around to feel them. Smaller ones can be noticed if they occur in more densely populated areas. The earth is always moving, and that movement is continuously recorded at instrument sites monitored by the Pacific Geosciences Centre near Victoria. Earthquake sensors called seismometers are installed at isolated locations along the coast. They can detect vibrations from earthquakes that happen in other parts of the world, as well as ones centered nearby. These sensors receive signals from the Global Positioning System (GPS), and are so sensitive that they can detect trucks rumbling down the highway a kilometre away. But these kinds of vibrations are recognized and filtered out electronically during analysis. Each seismometer is connected to a geophysical-data digitizer, a device which converts the vibrations recorded by the seismometer into a radio signal that is sent to the Pacific Geosciences Centre.

There, the data is analyzed by Tim and other men and women working in earthquake seismology. They can't predict earthquakes, but they have theories and can estimate the probability of a future big earthquake on the West Coast. "Mostly earthquakes give us great excitement," says Tim. Most people get worried if they feel an earthquake, but Tim is different. He gets downright enthusiastic. Few earthquakes in British Columbia cause any damage or injury. There's so much to be learned from each earthquake - what happened, why, and the effects on the area. After things calm down, they analyze the data from their sites.

In winter, Tim analyzes data and builds data digitizers from scratch. He works with an engineer who sketches out the basic design. Tim then adds meat to the bones by designing the circuit board on computer, and putting the prototype together from individual electronic components. Once he has a working prototype he contracts out the assembly of the required units to a local electronics company, and then tests each one when it is delivered. A data digitizer fits inside a weatherproof box that is about one foot square in size.

Tim contracts out the work to construct new sites based on his drawings to local communications companies. This building work involves pouring concrete for the seismometer vaults, setting up antenna towers, and installing the basic telecommunications equipment. Tim then goes to each new site for a day, installs the more delicate equipment, and adds that site to the list of 30 sites he visits and inspects each summer on Vancouver Island, the Queen Charlottes, and the lower mainland. The antennas and solar panels are sometimes damaged by lightning, ice, and snow. These inspections can involve week-long trips to a number of sites, with Tim operating a four-wheel drive truck. Sometimes he hires a helicopter to reach remote mountain top sites, but more often he hikes in through the bush for a kilometre or more. He carries a cell phone or a two-way radio in the field.