地面與鞋材之摩擦效應

The Effects of Floor Surface and Footwear Materials on Friction

滑倒或跌倒是職業傷害中最常見的職災類型之一。鞋子／地面間的摩擦係數是導致滑倒的重要影響因素。過去研究著重在標準測試材料與光滑地板，這些標準材料與地板在現場不常見，特別是工地或斜坡道。因此，本研究針對國內斜坡道常用之金屬材料以及鞋子，使用Brungraber Mark II進行摩擦係數測定。研究發現不同鞋底摩擦係數不同，一般安全鞋著重在耐壓設計，使用較硬的材質，其摩擦係數較低（0.46）。相對地，鞋底紋路經過良好設計的耐油污安全鞋，其係數可達0.55。這一點可以作為安全鞋設計的參考。工地用膠鞋摩擦係數比短統PVC無塵鞋高（0.54vs.0.51）。不同地面狀況對摩擦係數的影響不同，由大到小分別為乾燥（1.05）＞含水（0.62）＞清潔劑（0.23）＞油污（0.15）。顯見有油污或清潔劑的地面，摩擦係數顯著低於乾燥或含水的地面。這兩種地面狀況，很可能導致滑倒，特別是在傾斜步道。如果油污很難避免，應考慮地面與鞋子的選擇。不同地板摩擦係數不同，分別為（1）鋁一五爪（0.59），鐵一單爪（0.58），以及（2）鋁一單爪（0.49）、鐵一光面（0.45）、白鐵一光面（0.46）兩大類。如果使用抗滑性較佳的鞋底以及有紋路的地板，相較於沒有紋路的地板以及抗滑性較差的鞋底，其間摩擦係數的差異達0.2以上。這一部份可以作為安全鞋設計以及傾斜步道安全管理的參考。

Slips and falls are among the most common causes of occupational injuries. The shoe/floor coefficient of friction (COF) is the key factor to slip. Most measurements were performed with standard test materials on smooth floor. However, these materials and floor characteristics are rarely used in workplace, especially in construction site or ramp. Therefore, the commonly used shoes and floor materials in workplace were selected and their COFs were tested with Brungraber Mark II in this study. The results of the study showed that the shoe/floor friction coefficient was different from different shoes in a range between 0.46-0.55. Safety shoes are generally designed with hard materials for the purpose of anti-pressure. Such kind of safety shoes usually had a significantly lower COF, 0.46. On the contrary, slip-proof safety shoes with special sole texture had a higher COF, 0.55. The results from this anti-slip testing could be taken into consideration for safety shoes design. The COF of rubber shoes was higher than that of clean room boots, 0.54 vs. 0.51. The surface contaminant had significant influence on friction coefficient, dry (1.05), wet (0.62), sanitary liquor (0.23), and oil (0.15). Contaminated floor is slippery than clean surface. According to the result, slipping is very possible while walking on oily or contaminated surface, especially on a ramp. The coefficient of friction also varied with different floor type, ranging from 0.46-0.59. The COFs of floor with texture were higher than those of smooth floor type. The difference of COF between textured floor/anti-slip safety shoes and smooth floor/common safety shoes is above 0.2 under contaminated condition. The results of this study could be used not only for shoes design, but also for safety management of walkway and ramp.