Before accepting a person drawn as a grand juror, the court shall be satisfied that such person is duly qualified to act as such juror. When a person is drawn and found qualified he shall be accepted unless the court, on the application of the juror and before he is sworn, excuses him from such service for any of the reasons prescribed in this title or in Chapter 1 (commencing with Section 190), Title 3, Part 1 of the Code of Civil Procedure.