Left tackle Joe Staley knows the eardrum-rattling peril that awaits the 49ers in Saturday's visit to Seattle's CenturyLink Field.

"It's the loudest stadium in the NFL, so it's very difficult to play there," Staley said Wednesday. "It so loud, and you can't hear anything. Huge home-field advantage."

No stadium has had more false-start penalties by opponents since 2005 (110 in 55 games). The 49ers had only one such penalty in last season's opener in Seattle but still fell 31-6.

"It's a unique environment going up there," 49ers quarterback Alex Smith said. "Obviously we play there every year, but it's still something ... another thing we're going to have to overcome."

Saturday's five projected starting linemen have combined for 13 false-start penalties this season, including six on Staley and three on right tackle Anthony Davis. The solution for Saturday's earache: preparation.

"When you get jumpy, you're unsure of adjustments and start forgetting snap counts," Staley said. "You can quiet that nervousness by preparing during the week."

Although the line has had mixed results, technique issues and miscommunication often have been their downfall, rather than lack of discipline. The 49ers did not allow a sack in Monday night's 20-3 win over the Pittsburgh Steelers. Only six holding penalties have been called on 49ers linemen, including three on left guard Mike Iupati.

  • Linebacker Patrick Willis donned his No. 52 jersey before practice but did not participate, as has been the case since he strained his right hamstring Dec. 4. Willis continued his rehabilitation on a side field at the start of practice. He said Tuesday he hoped to play Saturday but was taking a safe approach to his recovery.

  • Wide receiver and return specialist Ted Ginn did not practice because of an ankle injury he suffered Monday night when he returned the second-half kickoff. The severity of his injury is unknown.

  • Defensive tackle Justin Smith received a late surge to take top honors at his position in fans' Pro Bowl voting. He edged the Detroit Lions' Ndamukong Suh by 8,626 votes out of 1,042,530 cast between the duo.

  • Special-teams ace Blake Costanzo's absence from practice was not injury related, according to the 49ers. No other details are known.

  • Alex Smith wasn't among the top five NFC quarterbacks in fans' Pro Bowl voting. Coach Jim Harbaugh has made recent declarations that Smith is Pro Bowl worthy. Smith's response: "You know, it's nice. Any time a quarterback's getting credit or recognition it's really a credit to the guys around him -- everybody, coaches and players included."