For those still wondering about the best time for trick-or-treat rounds this weekend, a reminder:

Officials in Prince George's and Montgomery counties recommend celebrating Halloween tonight; that is when extra police patrols will be on duty. The District of Columbia and counties in Northern Virginia, on the other hand, have decreed Sunday, Halloween's traditional date, as the official day.

The Department of Health and Human Services, the American Association of Poison Control Centers, and various police agencies have issued warnings about Halloween trick-or-treating this year. All recommend essentially the same precautions:

* Children should not go out without parents.

* Parents should bring along some candy from home to eat along the way so children are not tempted to dip into an unexamined bag.

* Children should be told not to take candy from strangers or from the ground near the houses they visit.

* Trick-or-treating should be limited to the houses of friends and neighbors well-known to parents.

* Adults should not allow children to eat anything collected on their rounds without first examining it for tearing, pinholes, offcolor smell or taste, or other signs of tampering.

* Suspect candy or food should be destroyed, not just thrown out, so that it cannot be retrieved by pets or children later.