Soak wood chips in water at least 1 hour. Preheat smoker according to manufacturer's directions to maintain a temperature of about 225°F. Use wood chips and water pan as directed.

Pat brisket dry with paper towels. Trim excess fat to about ⅛ inch. Rub brisket with oil and Worcestershire sauce; sprinkle generously with rub. Let stand at room temperature for 1 hour. Spray generously with cooking spray.

Place brisket, fat side down, on a well-greased rack in smoker directly over water pan; close smoker. Smoke for 4 to 6 hours or until thermometer inserted into meat reaches 160°F to 170°F.

Remove meat from smoker. Place brisket, fat side down, on a double layer of foil coated with cooking spray; also spray the brisket. Place a piece of unwaxed butcher paper over the top of the brisket and tightly crimp the edges of the foil and the butcher paper together. Return to smoker.

Smoke brisket up to 10 hours or until internal temperature reaches 203°F.

Remove brisket from smoker; wrap in a heavy towel and let stand 3 hours before slicing.