As the popularity of electric-powered bikes rises, Marin County officials are warning of increased accidents, especially among youth, and encouraging families to choose safer options if they are purchasing an e-bike for the holidays. New data released earlier this month showed that e-bikes made up a quarter of all bike-related 911 calls since early October, when the county began to distinguish the two. Forty percent of those accidents involved youth ages 10 to 19, while the rest were over 19 years old. No accidents involving e-bikes occurred in West Marin during this period, but deputies have given warnings to e-bike riders about helmet use and passengers. “I’ve heard of a couple students being stopped by law enforcement due to not having helmets on while riding on Sir Francis Drake,” said Laura Shain, principal and superintendent of the Lagunitas Community School. Understanding e-bike classes is particularly crucial for families as they approach the holiday season. “We fully support getting kids and adults on bikes, including e-bikes, as a healthy and fun way to get around independently,” Marin County Public Health Officer Dr. Matt Willis said in a press release. “The message is really about doing it more safely.” There are three classes of e-bikes. Class one has a maximum speed of 20 m.p.h. with pedal assist, while class two can reach 20 mph with a throttle. Neither type has a minimum age restriction but both require helmets for riders under 17. Class three e-bikes reach up to 28 m.p.h. and riders must be at least 16 and may not transport others. Gwen Froh, director for Marin County’s Safe Routes to School program, does not recommend that children under 16 operate class two e-bikes, adding that most accidents occur at high speeds. E-bike rules vary across the county. G.G.N.R.A. permits all e-bikes with pedal assist on designated paths, with a 15-m.p.h. speed limit. The Point Reyes National Seashore allows class one bikes wherever traditional bikes are permitted, unless otherwise specified. Marin Water prohibits e-bikes on all unpaved roads and trails, while Marin County Parks allows class one and two bikes on paved pathways but prohibits them on unpaved fire roads and multi-use trails.