UL 94 HB flammability standard(UL94 HB可燃性標準)
Specimen 試片
Length 125 mm (5 in) x Width 13 mm (0.5 in) x Thickness [typically 1.5 mm (1/16 in) or 3.0 mm (1/8 in) or 6.0 mm (1/4 in)].
Three specimens of each thickness are tested after conditioning for 48 hours at 23 degrees C and 50% RH.
每一種厚度準備了三個試片，測試前先在23℃和50%相對濕度下放置48小時。
Each specimen is mounted with its long axis horizontal and its short axis at a 45 degree angle.
每一試片以長軸呈水平、短軸呈45°方式固定。
Each specimen is marked with two lines, 25 mm and 100 mm from one end of the specimen.
每一試片在25mm及100mm處畫線做記號。
Each specimen is supported at one end such that its lower edge is 10 mm above a piece of wire gauze.
每一試片之一端固定，低緣下方10mm處水平放置一片金屬細網。
A 20 mm high blue Bunsen burner flame is applied to the free end of the specimen for 30 second and then removed. If the specimen continues to burn after the removal of the test flame, the time for the flame front to travel between the two gauge marks is measured and the burning rate calculated in millimeters per minute.
一個20mm高藍色本生燈火焰燃燒試片未固定之一端30秒鐘然後移開。 在火焰移開後假如試片繼續燃燒，則測出火焰由前緣燃燒至2個記號之間所用的時間。 燃燒速率以mm/min計算。
Requirements for HB HB等級的判定標準
The specimens may not have a burn rate exceeding 40 mm per minute over a 75 mm span for specimens having a thickness of 3.0 mm to 13 mm, or
3.0mm到13mm厚度之試片，沒有一個在75mn距離內燃燒速率超過40mm/min或
The specimens may not have a burn rate exceeding 75 mm per minute over a 75 mm span for specimens having a thickness less than 3.0 mm, or
小於3mm厚度之試片，沒有一個在75mm距離內燃燒速率超過75mm/min或
The specimens cease to burn before the flame reaches the 100 mm mark.
火焰在接近100mm記號前中止燃燒。
发表于 2004-9-11 12:38:33
