Their propriety, simplicity, and elegance, would make them the safest model for any young woman.

And researchers do not know whether newer windmills, which have huge blades that rotate slowly, are any safer for birds and bats than older models, which spin more like airplane propellers.

The safer models, she said, have something called a sequential-trip trigger.

No one would want to live with a pacemaker that could unexpectedly kill them and many patients would undoubtedly insist on having their pacemaker's lead removed and replaced with a safer model.

Among single-engine planes, those with refinements like a pressurized cabin, retractable landing gear and more powerful engines may not be any safer than smaller, more basic models, experts say.

This version is the safest model in the Long March 2 family, with 7 launches and no failure record.

The 15 companies that agreed to the voluntary standards have until 2009 to put safer models on the road.

If the current automatic opener was installed before 1982, consider replacing it with a safer model that complies with the Underwriters Laboratories standards, which were upgraded in 1982.

It is a structured and safer model.

The concept of uncertainty on which chaos theory relies is not an appealing motive for change compared to many alternative "safer" models of organizational change which entail less risk.