
386 S.E.2d 73 (1989)
96 N.C. App. 495
Randy Dean McDANIEL
v.
DIVISION OF MOTOR VEHICLES.
No. 8922SC62.
Court of Appeals of North Carolina.
December 5, 1989.
*74 Hall & Vogler by E. Edward Vogler, Jr., Mocksville, for petitioner-appellant.
Attorney General Lacy H. Thornburg by Asst. Atty. Gen. Robert E. Cansler, Asheville, for respondent-appellee.
PARKER, Judge.
The sole issue presented on this appeal is whether the trial court erred in finding that petitioner wilfully refused to submit to the breathalyzer analysis. Petitioner contends that he was deprived of his statutory rights under G.S. 20-16.2 when he was written up as a refusal before the expiration of the 30-minute statutory time period. Petitioner further asserts that if he had been allowed to take the test when his father *75 arrived, the test could have been administered within the statutory period.
General Statute 20-16.2 provides that any person charged with driving while impaired and required to submit to a breathalyzer examination "has the right to call an attorney and select a witness to view for him the testing procedures, but the testing may not be delayed for these purposes longer than 30 minutes from the time he is notified of his rights." G.S. 20-16.2(a)(6).
Relying on Etheridge v. Peters, Comr. of Motor Vehicles, 301 N.C. 76, 269 S.E.2d 133 (1980), petitioner argues that he was entitled to take the test anytime within the 30-minute period after he was notified of his rights. Etheridge, however, is distinguishable on its facts. Unlike petitioner in this case, Etheridge informed the officer at the time he was advised of his rights that he wanted to call a lawyer. Etheridge was then offered the test at the expiration of 20 minutes and again at the expiration of 30 minutes, but refused each time. Thereafter, when 35 minutes had passed, Etheridge elected to take the test, and the officer refused to administer it. In the instant case, when petitioner refused to take the breathalyzer examination at 9:13 p.m., seven minutes after he had been advised of his rights, he gave no indication whatever that he intended to exercise his right to call a lawyer or have a witness present. Petitioner did not state that he would take the test but only when his father arrived until ten minutes later, at 9:23 p.m., when the officer advised petitioner that he was being written up as a refusal and cut off the machine. The record is devoid of evidence as to what, if anything, occurred during this ten-minute interval. Seders v. Powell, Comr. of Motor Vehicles, 298 N.C. 453, 259 S.E.2d 544 (1979) and In re Vallender, 81 N.C. App. 291, 344 S.E.2d 62 (1986), cited by petitioner, are similarly distinguishable. In both of these cases, the petitioner indicated a desire to call a lawyer or a witness at the time the petitioner refused the breathalyzer test.
Under G.S. 20-16.2(a)(6), the only purposes for which the test may be delayed are for the defendant to call an attorney and to select a witness to view the test. Since driving while impaired is an implied consent offense, the 30-minute period is a grace period to enable defendant to have the benefit of these statutory purposes. Therefore, to permit a defendant to delay the breathalyzer examination for any period of time without affirmatively indicating his intention to call a lawyer or to have a witness present would be contrary to the express intent of the statute.
In upholding the constitutionality of the 30-minute limitation on the length of the permitted delay, our Supreme Court recognized the State's need to obtain chemical evidence before the metabolic processes of the body obscure such evidence. Seders v. Powell, Comr. of Motor Vehicles, 298 N.C. at 463, 259 S.E.2d at 551. For this reason to avoid obstruction of the testing procedure by impermissible delay, the burden must be on the person arrested for driving while impaired to assert at an early stage his intention to exercise his statutory right to a lawyer and witness.
Accordingly, we hold that petitioner, having failed to indicate at the time he refused to take the breathalyzer examination that he desired to have a witness present, waived his statutory right to delay the test until after his witness arrived, even if the witness arrived within the 30-minute period. Petitioner's refusal, made with full knowledge of his rights, but without explanation, was thus wilful within the meaning of G.S. 20-16.2(d).
Although not necessary to our resolution of this appeal, we note with respect to petitioner's second contention that the record reveals only that petitioner's father arrived a "short time" after petitioner was told that he had refused the breathalyzer test. No evidence in the record shows conclusively, however, that petitioner's father arrived within the 30-minute period.
For the foregoing reasons, the decision of the trial court is affirmed.
Affirmed.
WELLS and PHILLIPS, JJ., concur.
