Table 5

Factors contributing to nail gun injuries* among union residential carpenters by trigger mechanism of tool, 1999–2002; values are number (%)

Type of trigger mechanism†
Contributing factorContact trip trigger (n=53)Sequential trigger (n=18)
*Categories are not mutually exclusive.
†Triggering mechanism unknown for nine injuries.
Use of non-dominant hand to handle tool6 (11)2 (11)
Placement of hand not holding tool/body (bracing materials, shooting towards self)18 (33)9 (50)
Awkward posture (work in rafters, leaning over, overhead, shooting back towards self)8 (15)3 (17)
Nail ricocheted (knot, laminated beams, metal truss components)12 (23)6 (33)
Rapid double fire, uncontrolled, misfire17 (32)1 (6)
Penetration of wood surface11 (21)4 (22)
Projectile nail9 (17)0
By-passed safety mechanism19 (36)0
Lack of eye protection2 (4)1 (6)