HANOVER, N.H. (AP) – The family of a Dartmouth College student who died following a skiing accident on a school-owned slope is upset that the college doesn’t require all skiers to wear helmets.

Prompted by the injury that led to Christina Porter’s death last month, the school now requires students and instructors in physical education classes to wear helmets. The rule also applies to anyone under 18 taking lessons, either privately or through the college’s programs.

But others using the slope, which is open to the public, are not required to use safety gear. The new policy took effect in November.

“It’s simply unconscionable for Dartmouth College to only require helmets for students enrolled in skiing and snowboarding classes,” Christina’s father, Brent Porter, said in a letter to students who attended his daughter’s memorial on Jan. 28.

James Larimore, dean of the college, said mandatory helmet use for all skiers has been discussed, but school officials decided it would be difficult to enforce for adults.