# Field Measurements of Free Ascending Behavior of Occupants along Medium-Long Stairway
## 1 Introduction
### Research Works on Ascending Speed on Long Stairways  
For the study on the ascending speed on a long stairway, [PERSON] et al. [21] found an average upward speed of approximately 0.387 m/s through observing the upstairs walking speeds at the outer stairway of the Dutch pavilion at the Expo 2000 in Hannover. They also found that the mean upward walking speed on the short stairway was roughly twice as large as the one on the long stairway. [PERSON] [15] conducted an experiment in a 50-storey residential building in Korea involving 30 young male and 30 young female participants to measure the individual ascent and descent walk speeds. They found that the average descent speed for the male and female population was 0.83 m/s and 0.74 m/s, respectively, and the average ascent speed was 0.66 m/s and 0.48 m/s. There was no significant relationship between Body Mass Index (BMI) and stair walk speed. During the ascent, all participants decreased their speed over the first 20 floors by an average of approximately 60%, and fatigue may be a main factor. For males, the average ascent speed over the first 25 floors was 0.75 m/s, while, over the last 25 floors, it was 0.55 m/s with the average overall being 0.65 m/s. For females, it was 0.53 m/s over the first 25 floors and 0.42 m/s over the last 25 floors with an average of 0.47 m/s. [PERSON] et al. [22] conducted a controlled experiment on ascending stairs in a typical residential building with 40 floors in Hong Kong. Through the experimental observation of four groups of participants of different ages ascending stairs, they found that ascending speed was related to the age of the participants, and the average walking speed of children and elder people was lower than that of young people. The women's walking speed was also lower than that of the men, and the average speed along the stairs was about 0.498 m/s. The difference between the maximum levels the participants could reach were large, ranging from 3 to 20 levels, also depending on age. [PERSON] et al. [23] conducted an experimental study on the individual movement behavior of people in a 20-floor building along the stairs, and found that for long-distance upward evacuation, the upward walking speed along the stairs gradually decreased with the rise in the floor for the first 14 floors, and after that, the upward walking speed was maintained at around 0.68 m/s for the males and 0.52 m/s for the females. No obvious correlation between BMI and ascent speeds was found for males, and for females with overweight, they had the lowest ascent speeds. [PERSON] et al. [12] conducted a two-year research project to investigate the effects of fatigue on walking speeds, physiological performance, and behaviors in the case of long ascending evacuation. Four experiments were conducted during the research project, involving two sets of (individual and group) experiments on ascending stair evacuation, one set of (individual and group) experiments on ascending evacuation on a stopped escalator, and one individual laboratory experiment on ascending evacuation on a stair machine. The results included walking speeds and physiological measures of physical exertion (oxygen consumption, heart rates, and electromyography data). Perceived exertion and behavioral observations were presented. The results showed that physical work capacity affects walking speeds in the case of long ascending evacuation and it should be considered while using long ascending evacuation in engineering design. The design of stairs and effects of fatigue may have a greater impact on walking speed. A simple model to predict human performance during ascending evacuation that can serve as a base to predict individual and group performance was developed. Reviews on walking speed on evacuation were reported [6; 24], with a summary on free ascending speed on the long stairway summarized in Table 1. Large differences were found between different research works. This might be attributed to the different data collection methods and assumptions made in the analysis of the data.