Cold weather can require additional precautions when you walk or drive on icy surfaces.

People with certain diseases, skin conditions, or taking certain medications may require additional precautions.

But the missions that involve returning samples (or astronauts) to Earth require the most planning and precautions.

Those headed abroad to places where diseases like malaria and yellow fever are a problem require extra precautions.

The proposals would require safety equipment, training, and other precautions tailored to the work site.

The lack of suitable geophysical data on the reservoir required serious precautions.

It requires special precautions and licensing, since radioactive substances are used.

Doctors found that the leaks had produced no symptoms and did not require medical precautions or treatment.

Apparently an American citizen born in Hungary required extra precautions.

Ms. Pope acknowledged that mail in the time of anthrax may require special precautions.