Instead of driving a car or taking public transportation, many commuters ride their bicycles to work. This is more environmentally friendly than driving and takes up less space in crowded cities. However, there are significant problems with safety on the roads when cyclists commute.



First, a major problem involves traffic signals. Most road and traffic systems are designed for cars, not bicycles, and so the intervals at which traffic signals are placed are established with cars in mind; for this reason, cyclists typically encounter many more red signals than cars do during their commute. Having to stop at so many red signals is frustrating and stressful for cyclists. Perhaps because of this, cyclists are significantly more likely to go through red signals without stopping than cars are, putting themselves and others at great risk of collision.



Second, commuting to work by bicycle often requires strenuous exercise. If cyclists regularly experience fatigue due to strenuous exercise, they will be tired during their commute to and from work. This tiredness may make them less attentive and less alert to what is happening around them. This in turn may increase the likelihood that these cyclists will be involved in accidents on the road.



Third, because many cyclists need to commute at times when there is no sunlight, they place themselves and others at risk as they light their way. When it is too dark for drivers in cars to see cyclists, or for cyclists to see the road in front of them, the cyclists often attach bright lamps to their bicycles. These lamps, which point forward so the cyclist can see as much of the road as possible, are often designed to flash, with intermittent pulses of light; although this may seem like an effective way for cyclists to alert others to their presence, those flashes of light can be very distracting to other cyclists and drivers and could cause accidents