If a damaging earthquake could have a silver lining, it would be the safety improvements that follow it. That silver lining for the 1971 Magnitude 6.7 Sylmar earthquake in southern California, 45 years ago today, is safer hospitals.
The Sylmar quake caused several dramatic consequences, including one similarity to last week’s M6.4 Taiwan earthquake: its recorded ground motions were surprisingly high for a relatively small magnitude.
But the most significant outcome of the Sylmar quake was substantial damage to hospitals, including the Olive View and Veterans Administration complexes. It was bad enough that this damage caused most of the quake’s 58 fatalities, but even worse was the loss of hospital capacity to care for people injured by the quake.
On the other hand, Sylmar was a success story for schools. Thirty-eight years earlier in the 1933 Long Beach earthquake, school collapses led to emergency legislation requiring schools to be built to a higher seismic standard than other buildings.
Schools built after 1933 using the higher standards experienced significantly less damage than pre-1933 facilities. (The Sylmar quake occurred at 6am local time when children were not occupying schools.) This sent a strong signal: safety legislation works.
After the Sylmar quake, lawmakers and the public agreed that a shortage of post-quake health care is inexcusable. In 1973 legislation was passed requiring a higher standard of construction for hospitals, so they are reasonably capable of providing services to the public after a disaster.
Hospitals built since 1973 conform to the new standard, while hospitals built prior have been required to upgrade.
The Sylmar earthquake also precipitated other important programs including:
- Alquist-Priolo Special Studies Zone Act, which prevents new construction on known faults and requires disclosure upon sale of any property on a known fault.
- Strong Motion Instrumentation Program, which improves scientific measurement of shaking intensity and its effect on buildings and infrastructure.
Each earthquake teaches us something. What have you learned from a quake?