Posts mit dem Label advanced age werden angezeigt. Alle Posts anzeigen
Posts mit dem Label advanced age werden angezeigt. Alle Posts anzeigen

Freitag, 26. September 2008

Who, When, Where Died (US, 2006)

Gender
- 69% of pedestrians killed were males, a proportion that has varied little since 1975.

Alcohol
- 54% of pedestrians 16 and older killed in nighttime (9pm - 6am) crashes had blood alcohol concentrations (BACs) at or above 0.08 %, compared to 23% during the day (6am - 9pm).

Where
- 72% of pedestrian deaths occurred in urban areas, up from 59% in 1975.
- 36% of pedestrian deaths among people 70 and older occurred at intersections, compared with 21% for those younger than 70.
- 72% of pedestrian deaths occurred on major roads, including interstates and freeways.
- In urban areas, 54% of pedestrian deaths occurred on roads with speed limits of 40 mph or less; in rural areas 24% of deaths occurred on such roads.

When
- 46% of fatal pedestrian motor vehicle collisions occurred between 6 pm and midnight.
- The greatest proportion of pedestrian deaths occurred on Saturday (17%) followed by Friday and Sunday (both 16%).

A lot of statistics and overviews for 2006 www.iihs.org

Dienstag, 23. September 2008

Vehicle-Pedestrian Crash Sites

· Accidents at sites without sidewalks are twice as likely to occur – “sites with no sidewalks were the most hazardous to pedestrians, and least hazardous where sidewalks are present on both sides of the road.” - H.N. Tobey, E.M. Shunamen, and R. L. Knoblauch, Pedestrian Trip Making Characteristics and Exposure Measures, DTFH61-81-C-00020, Federal Highway Administration, 1983. - Synthesis of Safety Research – Pedestrians August 1991 Pub. no. FHWA-SA-91-034 page 83
http://www.pedestrians.org/index.html#quotes
· Pedestrian crashes occur most frequently in urban areas where there is greater traffic volume and increased pedestrian activity
· 65 percent of crashes occur at non-intersections; however, this is correlated to the age of the pedestrian involved – under 45 at non-intersections, 45-65 equal for intersections and non-intersections, age65 and older more likely to occur at intersections
http://www.walkinginfo.org/pedsafe/crashstats.cfm
PDF:
http://www.walkinginfo.org/pedsafe/downloads/pedsafe_ch2.pdf
· According to the National Pedestrian Crash Report, by the National Center for Statistics and Analysis, 78% of pedestrians were killed at non-intersections and 21.2% were killed at intersections over the past decade
· Roadways without crosswalks accounted for 42% of all pedestrian fatalities (see chart p. 19 – 2006 in pdf at link below for a more legible chart)
http://www-nrd.nhtsa.dot.gov/Pubs/810968.PDF

http://www-nrd.nhtsa.dot.gov/Pubs/810968.PDF

Accommodation (only relevant to close vision)

Process in the eye which permits clear vision at various viewing ranges. By contraction of the cilliary muscle the elastic lens is tightened which leads up to a change of the optical refraction power of the eye. Parallel on this a convergent motion (approaching one another) of the eyes is taking place to allow the optic axis' to cross in the fixation point. In addition to this a pupil constriction (convergent myosis) appears. These 3 mechanisms build up the so called "close-up triad" (not too sure about this translation :->), which controlls the capacity of close vision. In advanced years this capacity decreases strongly (onward stiffening of lens) and can enhance the minimum visibility range from 4 to 19,7 inch.