Reserve component troops called to active duty in support of Operation Desert Shield have taken comfort in knowing that President Bush can only keep them in the Saudi Arabian desert for 180 days.

Until now.In the waning hours of the 101st Congress, lawmakers made it possible for the president to double the time combat units from Guard and Reserve components for as long as 360 days.

The change does not affect any of the 32 Utah Army National Guard troops who were called to active duty Aug. 24, but it could affect Utah National Guard and Reserve troops called up in the future if they belong to infantry, artillery or armored combat units, said Lt. Col. Barrie Vernon, judge advocate general for the Utah Army National Guard.

Vernon said the change was made so quietly that he first read about it in a newspaper clipping. "It really surprised me, and I think it surprised a lot of congressmen," Vernon said.

Before Congress changed the law, the president had authority to activate reserve component troops for 90 days and could extend that call for an additional 90 days. After that, only a congressional declaration of emergency or declaration of war could keep the part-time soldiers on active duty.

The same rule applies with the exception that the president's authority over reserve component troops is now extended to 360 days for combat units.

"I think the theory behind it is because they're going to need more time to train the combat troops," Vernon said. "A good example of this is that the Guard units activated (Thursday) are not going directly to Saudi Arabia."

Tank units activated by the president Thursday are being sent to the California desert first for training. "By the time you call them up, give them a month's training and get them over there you've lost most of your six months," Vernon said.