By referring thirty-seven previous studies on manual material handling (MMH), this paper analyzed guidelines and main factors of one-handed tasks. The previous studies concerned main factors of distance, weight, frequency, posture, gender, age, training, direction of force, height of the force exerted, and object shape and size. Based on these factors, the criteria used to understand one-handed tasks were objective measures of maximum strength, reaction force, etc., psychophysical measures of maximum acceptable frequency and weight, etc., and physiological measures of oxygen uptake, heart rate, electromyography, etc. An allowance threshold model regarding quantitative and objective fatigue and workload would be suggested for future research. This study would be expected that it serve to establish and Korean recommendations of one-handed tasks.