EE2 was installing a liner pack into number 3 cylinder on the engine of 504 in bay 15. EE2 called down to EE1 for an additional tool. EE1 got the tool and reached up from below to hand it to EE2. EE2 turned to grab the tool from EE1, during that time EE2 bumped a 12-inch adjustable wrench that fell and hit EE1 above the left eyebrow.