I AM perturbed by the information that only some — not all — tall office buidlings in areas which felt the tremors of the Sumatra quake evacuated their tenants.

.Singapore's strict building regulations and geography mean there is only a negligible chance of building failures caused by earthquakes. However, leaving tenants in buildings while conducting structural checks is unacceptable in high-rise, high-density areas.

.With many buildings in the central area more than 20 stories high, the amount of time needed to evacuate the many tenants only upon discovery of any structural problems is inconceivable. The risk taken on the tenants' lives is too great.

.Consider pregnant women, who are less mobile. Surely, not all building management teams will know how many tenants who require special assistance there are, and where in the buildings they are, so they can render special attention during an emergency.

.An immediate evacuation while testing structural integrity during such events also provides the assurance to tenants, who should return only after all floors are deemed safe.

.With Singapore seeking to increase our population, we can expect greater human density in the country. The relevant authorities should be more serious about ensuring building safety.