With the time change, it's time to get out your lights. Here are the laws according to the California Vehicle Code:
http://www.dmv.ca.gov/pubs/vctop/d11/vc21201.htm(d) Every bicycle operated upon any highway during darkness shall be equipped (1) with a lamp emitting a white light which, while the bicycle is in motion, illuminates the highway in front of the bicyclist and is visible from a distance of 300 feet in front and from the sides of the bicycle; (2) with a red reflector on the rear which shall be visible from a distance of 500 feet to the rear when directly in front of lawful upper beams of headlamps on a motor vehicle; (3) with a white or yellow reflector on each pedal visible from the front and rear of the bicycle from a distance of 200 feet; and (4) with a white or yellow reflector on each side forward of the center of the bicycle, and with a white or red reflector on each side to the rear of the center of the bicycle, except that bicycles which are equipped with reflectorized tires on the front and the rear need not be equipped with these side reflectors. Such reflectors and reflectorized tires shall be of a type meeting requirements established by the department.
(e) A lamp or lamp combination, emitting a white light, attached to the operator and visible from a distance of 300 feet in front and from the sides of the bicycle, may be used in lieu of the lamp required by clause (1) of subdivision (d).
and
http://www.dmv.ca.gov/pubs/vctop/d11/vc21201_3.htm21201.3. (a) A bicycle or motorized bicycle used by a peace officer, as defined in Section 830.1 of, subdivision (a), (b), (c), (d), (e), (f), (g), or (i) of Section 830.2 of, subdivision (b) or (d) of Section 830.31 of, subdivision (a) or (b) of Section 830.32 of, Section 830.33 of, subdivision (a) of Section 830.36 of, subdivision (a) of Section 830.4 of, or Section 830.6 of, the Penal Code, in the performance of the peace officer's duties, may display a steady or flashing blue warning light that is visible from the front, sides, or rear of the bicycle or motorized bicycle.
(b) No person shall display a steady or flashing blue warning light on a bicycle or motorized bicycle except as authorized under subdivision (a).
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Even though the law doesn't require it, for safety (isn't that what it's really about?) I use a rear light rather than relying on a reflector
http://. I'd argue that my ankle reflectors are even more effective than pedal reflectors, since they're also visible from the sides, so I should be legal in that respect. Additionally, I use velcro spoke reflectors, I wear light colored gloves so hand signals are more visible and usually have a relective "Slow Moving Vehicle" sign attached to my backpack.
I find the first weekday evening commute after the time change (tonight) is really dangerous. It's feels like the car drivers haven't adjusted to the time change so they're all in a panic and mad rush mode because it feels like they're running late getting home.
Ride safe out there.
-ss