A safety intravenous catheter assembly (700, 800, 900) comprising: a needle assembly (710, 810, 910) including a needle hub (712, 812, 912) and a needle (718, 818, 918) having a proximal end secured to the needle hub (712, 812, 912) and a distal end defining a tip (718a, 818a, 918a); a catheter assembly including a catheter hub (720, 820, 920) and a catheter tube (721, 821, 921) extending distally from the catheter hub (720, 820, 920); and a safety device (713, 813, 913) including a housing (714, 814, 914) defining a cavity, a distal opening and a proximal opening and a biasing member (716, 816, 916) supported within the cavity, the distal and proximal openings being dimensioned to receive the needle (718, 818, 918), the biasing member (716, 816, 916) including a stationary portion (716a, 816a, 916a), a movable portion (716b, 816b, 916b) and a blocking arm (716c, 816c, 916c), the movable portion (716b, 816b, 916b) being movable in relation to the stationary portion (716a, 816a, 916a) from a first position to a second position; wherein in an assembled state, the safety device (713, 813, 913) is positioned between the needle hub (712, 812, 912) and the catheter hub (720, 820, 920), the needle (78, 818, 918) extends through the proximal and distal openings of the housing (714, 814, 914) of the safety device (713, 813, 913) and the catheter assembly, and the biasing member (716, 816, 916) is compressed between the needle (718, 818, 918) and the housing (714, 814, 914) such that the movable portion (716c, 816c, 916c) is in the first position in engagement with the needle, and in a disassembled state, the tip of the needle (718, 818, 918) is withdrawn through the distal opening into the cavity of the housing (714, 814, 914) of the safety device (713, 813, 913) and the movable portion (716c, 816c 916c) of the biasing member (716, 816, 916) is in the second position spaced further outwardly of the stationary portion (716a, 816a, 916a) such that the housing (714, 814, 914) is tilted in relation to the needle (718, 818, 918) to move the needle (718, 818, 918) out of alignment with the distal opening of the housing (714, 814, 914), characterised in that in the disassembled state, the blocking arm (716c, 816c, 916c) is positioned between the movable portion (716b, 816b, 916b) and the stationary portion (716a, 816a, 916a) to prevent movement of the movable portion (716b, 816b, 916b) from the second position back to the first position. a needle assembly (710, 810, 910) including a needle hub (712, 812, 912) and a needle (718, 818, 918) having a proximal end secured to the needle hub (712, 812, 912) and a distal end defining a tip (718a, 818a, 918a); a catheter assembly including a catheter hub (720, 820, 920) and a catheter tube (721, 821, 921) extending distally from the catheter hub (720, 820, 920); and a safety device (713, 813, 913) including a housing (714, 814, 914) defining a cavity, a distal opening and a proximal opening and a biasing member (716, 816, 916) supported within the cavity, the distal and proximal openings being dimensioned to receive the needle (718, 818, 918), the biasing member (716, 816, 916) including a stationary portion (716a, 816a, 916a), a movable portion (716b, 816b, 916b) and a blocking arm (716c, 816c, 916c), the movable portion (716b, 816b, 916b) being movable in relation to the stationary portion (716a, 816a, 916a) from a first position to a second position; wherein in an assembled state, the safety device (713, 813, 913) is positioned between the needle hub (712, 812, 912) and the catheter hub (720, 820, 920), the needle (78, 818, 918) extends through the proximal and distal openings of the housing (714, 814, 914) of the safety device (713, 813, 913) and the catheter assembly, and the biasing member (716, 816, 916) is compressed between the needle (718, 818, 918) and the housing (714, 814, 914) such that the movable portion (716c, 816c, 916c) is in the first position in engagement with the needle, and in a disassembled state, the tip of the needle (718, 818, 918) is withdrawn through the distal opening into the cavity of the housing (714, 814, 914) of the safety device (713, 813, 913) and the movable portion (716c, 816c 916c) of the biasing member (716, 816, 916) is in the second position spaced further outwardly of the stationary portion (716a, 816a, 916a) such that the housing (714, 814, 914) is tilted in relation to the needle (718, 818, 918) to move the needle (718, 818, 918) out of alignment with the distal opening of the housing (714, 814, 914), characterised in that in the disassembled state, the blocking arm (716c, 816c, 916c) is positioned between the movable portion (716b, 816b, 916b) and the stationary portion (716a, 816a, 916a) to prevent movement of the movable portion (716b, 816b, 916b) from the second position back to the first position.