(concurring) — I concur in the rationale of the majority except to the extent that it fails to deal with the seat belt-contributory negligence issue.
The problem is that the trial court did not instruct on the seat belt issue in the usual “contributory negligence is a complete bar” sense, but rather that such contributory negligence, if found, would bar recovery for such injuries or damages that would not have occurred had plaintiff been wearing a seat belt.
The so-called seat belt defense has been urged not only as contributory negligence, but alternatively as falling *771within the concept of avoidable consequences or apportionment or mitigation of damages. 53 Marquette L. Rev. 172 (1970).
A careful reading of Derheim v. N. Fiorito Co., 80 Wn.2d 161, 492 P.2d 1030 (1972), indicates to me that the court intended to reject all elements of the defense, that is, contributory negligence, avoidable consequences and apportionment or mitigation. I would dispel any doubt by so holding in this case. In addition to the cases cited in Der-heim, see Lipscomb v. Diamiani, 226 A.2d 914 (Del. 1967), and Romankewiz v. Black, 16 Mich. App. 119, 167 N.W.2d 606 (1969), which discuss and reject not only the contributory negligence concept, but its sub variations.
Rosellini, Hunter, and Wright, JJ., concur with Brach-TENBACH, J.