Fallout Shelter SPECIAL SPECIAL in " Fallout Shelter " works slightly differently than in other games as Skills do not exist in this game . Each SPECIAL attribute increases dweller efficiency in various rooms , during combat or when performing certain tasks . Keep in mind that although attributes can only be trained to a maximum of 10 , they can still be increased to up to 17 through clothing bonuses . These additional points will not be visible on the dweller ' s SPECIAL bars but can be checked by tapping / clicking the bars , which brings up a more comprehensive menu that lists any and all bonuses . Strength . Strength increases the speed at which power generators and Nuclear reactor s generate power . As with all other stats , a higher strength makes the dwellers take less damage in the wasteland . Stronger dwellers also have a greater chance at successfully opening lockers they find in the wasteland . Dwellers can improve their strength in the Weight room . Perception . Perception increases the speed at which water production rooms ( Water treatment and Water purification facilities ) produce water . During quests , it determines the speed of the critical hit indicator ; higher Perception decreases the speed the indicator moves , allowing the player to score the most powerful critical hits more easily . In the wasteland it helps dwellers to find locations . Dwellers can improve their perception in the Armory . Endurance . Endurance increases the speed at which the Nuka - Cola bottler creates food and water and it is also the assigned skill for the storage areas . Endurance determines how many hit points dwellers gain as they level up . Dwellers start with 105 health points . They seem to get 2 . 5 + ( END * 0 . 5 ) health points each time they level up , so 17 points in Endurance will add 11 hit points per level compared to the minimum of 3 at END 1 . To achieve maximum health , a dweller must equip heavy wasteland gear ( END + 7 ) at level 1 while already having 10 points in Endurance themselves . At END 11 or more , the dweller becomes immune to the occasional radiation bursts they suffer while exploring the wasteland ( note that this does not apply to real - time combat ) . These hit points are not retroactive . Dwellers can improve their endurance in the Fitness room . Charisma . Charisma determines the effectiveness of Radio studio s and Living quarters by increasing the likelihood of attracting new dwellers for the former and speeding up reproduction for the latter . It is also used during wasteland exploration to help explorers succeed in encounters with " civilized " persons or groups . Dwellers can improve their charisma in the Lounge . Intelligence . Intelligence determines the effectiveness of Medbay s and Science lab s . In the wasteland , intelligent dwellers have better chances at succeeding in encounters with wounded civilized persons ( such as injured sheriffs , wounded slaves , etc . ) , as well as dealing with certain enemy types . Dwellers with high Intelligence also have an increased chance of finding stimpaks and RadAways . Dwellers can improve their intelligence in the Classroom . Agility . Agility determines the effectiveness of food production rooms ( Diner and Garden ) . In quests or in the wasteland it determines how many shots they can fire before the enemy does or how much damage the dweller can avoid when fleeing from hopeless battles . Dwellers can improve their agility in the Athletics room . Luck . Luck determines if a production room also yields caps along with the normal room reward ( or extra caps after a successful rush attempt ) . Luck also affects the chance of rush attempts succeeding . In the wasteland , it increases the chances of finding items when dwellers go out on quests and explore locations in the wasteland . The higher the Luck , the better the items . During quest combat it increases the speed at which the critical hit meter fills . Dwellers can improve their luck in the Game room .