Fallout 3 traps Traps in " Fallout 3 " can be found all over the Capital Wasteland . Types of traps . Cars and motorcycles . Though more an obstacle to avoid than a trap , a large number of decaying vehicles can be found around the Capital Wasteland . These nuclear - powered vehicles , suffering from two centuries of neglect , will catch fire and explode if sufficiently damaged ( around five hits from a plasma rifle will destroy one outright ) . When a vehicle takes enough damage , it will release a small explosion and catch fire , giving the player several seconds to escape . Once that period has elapsed , the vehicle goes up in a much larger and more damaging nuclear explosion , similar in appearance and potency to a mini nuke . The explosion can be hastened by firing upon the flaming wreck . An exploding car can be deadly to anything nearby . Anything standing on or next to the car will more than likely be killed instantly . In addition , the explosion may set off other nearby cars , potentially without any delay if the Damage Threshold is achieved . In areas like parking lots , this can result in up to a dozen simultaneous nuclear explosions . NPCs and enemies will move away from cars that have caught fire and will eventually explode , but typically do not flee quickly enough unless they were already far enough away from the vehicle . This can be demonstrated by sniping the blue car in the parking lot near Meresti trainyard . Though cars are not technically traps , they are used as such in Minefield , which the player will likely first visit during the quest Traversing a Mine Field from the first chapter of Wasteland Survival Guide . The sniper Arkansas will deliberately fire on the cars from a distance should the player wander too close to them . Being cars , it is impossible to actually prevent this short of killing Arkansas ( who will have likely hit them anyway by the time you get in range ) or detonating them yourself , However you can avoid this by sticking to the buildings and moving in cover . If you cause a car to detonate , the splash damage counts as damage you inflict on NPCs and can make them hostile against you . If that splash damage kills a target , you do not get XP for the kill . Mine . Frag mines are a product of RobCo for military use and are commonly laid in areas occupied by hostile forces . They have a very sensitive sensor that registers vibration on the ground , and when the vibration exceeds a certain level , it detonates . Followers will trigger them as easily as the player . The length of the fuse is based on the player ' s explosives skill . The greater the skill number , the longer the fuse . They require an explosives skill of 1 to disarm , meaning any player can disarm one . They can be picked up after being disarmed . If any enemy or follower steps directly on to one there is a chance of them being killed instantly , as the blast could blow their leg off . If the player stands directly on one they will lose a large amount of health depending on the armor you are wearing . Bear trap . Bear traps are a spring - operated pair of spiked jaws that snap shut on the player ' s leg should the pressure switch in the middle be triggered . This can cripple the limb at lower levels . A repair skill of 25 is required to disarm them . Shooting the switch or dropping an object on it also works . Bear traps can be reset , but this requires a repair skill of 55 . Swing object . Swing objects are simple heavy objects ( often a girder , automotive engine , or rotting brahmin body parts ) chained to the ceiling and held up by a trip wire . When the wire is broken , the object swings down and impacts the player for a minor amount of damage . The trip wire requires a repair skill of 25 to disarm , or the object itself can be grab bed and manually moved to a safe " down " position without any required skill ( if it ' s too high to grab , you can usually trigger it from a safe distance by shooting it ) . Because of the nature of the trap , it can remain dangerous even after the initial trigger . At certain angles , especially if walked into , it will cause damage , often several times in quick succession . It can also cause damage when manually moved by the grab action . Grenade bouquet . The grenade bouquet is a cluster of three frag grenade s hung from the ceiling . When triggered , either by simply walking into it , shooting it , or hitting the nearby trip wire / pressure plate , the pins are pulled and the three grenades will fall to the ground . They explode after a few seconds . Both the tripping mechanism and the grenades themselves can be disarmed , the latter of which requires an explosives skill of 30 . Doing the latter adds the three grenades to the player ' s inventory . If the player lacks the required skill to disarm the trap , they may be able to shoot the rope holding up the grenades to make them fall and detonate , safely away from the player . This trap is extremely dangerous , as the combined force of three grenades can be deadly depending on the player ' s proximity to the blast . They make a tell - tale rattle noise when they fall , alerting players if they fail to notice the trap beforehand , but their vector does not appear on the HUD like thrown grenades . Trapped pipe . Similar to the grenade bouquet trap , some ventilation pipes have a grenade bouquet installed inside them , the payload of which is primed and deployed by the activation of a nearby pressure plate or tripwire . This trap is uncommon , but can be found in locations such as the ruins of Fairfax , just outside of Madame Jealle ' s in L ' Enfant Plaza , Arlington Library or the steelyard of The Pitt . They cannot be disarmed , though the trip wire or pressure plate can . When activated you will hear the sound of the grenade bouncing through the pipe and dropping onto the floor shortly before exploding . Pitching machine . Inside buildings , pre - War pitching machines have been set up as weak traps . A nearby pressure plate or trip wire triggers the machine , which fires about ten baseballs before exhausting its supply . Either part can be disarmed . The danger of the machine lies more in the noise it makes , as the baseballs do very little damage . Any nearby enemies will be alerted by the thunking noise it makes when in operation . An excellent example of this trap can be found in the Arlington Library ; in addition to the danger of flying baseballs in the choke point , the noise from the trap attracts raiders . There is also a modification of this trap in the add - on Point Lookout — a pitching machine there shoots 8 baseballs and 2 frag grenades , making it a deadly trap for a character who is already wounded . Gas leak . Gas leaks are areas which have filled with natural gases that ignite if any sort of combustion occurs within the area of the leak . They are usually found in tunnels and can be visually detected by noting a wavering distortion in the air . When a gas leak is ignited , anything in the immediate vicinity takes a small amount of damage , is set on fire , and is knocked down for a few seconds . This can be particularly dangerous in combat situations if the player is caught in the explosion and the enemy is not . Guns will set off a gas leak if fired within a cloud but not from outside . Energy weapons , such as the laser pistol , will set off the leak if the shot intersects the cloud at any point ( this is noted by a user manual for the laser pistol found in the Metro - Central station . Energy weapons from add - ons do not seem to do this ) . The detonation of any kind of explosive , such as a frag grenade , within the cloud will also set off the leak . Finally , any item with an open flame , such as the flamer , heavy incinerator , or Shishkebab , will ignite the gas if it comes into contact with the cloud , regardless of whether or not they are actually fired , since the pilot light used to ignite them is active . Holstering them will prevent this . To safely remove gas leaks , ignite them from a safe distance ( laser pistols are good for this purpose ) . Pinkerton uses the gas in combination with the grenade bouquet : by triggering the tripwire , the grenades will drop , and the explosion will ignite the gas . However , unless the player did not kill the mirelurks on the lower level , this is at best a minor inconvenience , as the gas fills the entire hallway and the player will probably have left the range of the grenades . Radiation trap . Radiation traps are added with the " Broken Steel " add - on . As the name suggests , they release intense radiation when active . They require a repair skill of 60 to disarm . Only two locations in the game feature them : Holy Light Monastery , where they can only be activated manually ; and Olney Powerworks , where they are triggered as a security measure before you ever get near them and must be shut down using a nearby terminal . Rigged shotgun . The rigged shotgun is a simple but dangerous trap consisting of a combat shotgun wired to a pressure plate or a trip wire . When triggered , it fires a single blast at the position of the trigger . A repair skill of 45 is required to disarm the gun itself . Disarming the gun rewards the player with a combat shotgun , four shotgun shells and 10 microfusion cell s ( used to power the mechanism which pulls the trigger ) . Unlike traps such as grenade bouquets , rigged combat shotguns can be disarmed after having been triggered . Rigged baby carriage . A particularly devious and complicated trap , the rigged baby carriage consists of a perambulator containing a toy baby head with a bomb and several frag mines strapped to it . Upon approaching the carriage , the toy will emit a crying sound ( an unfamiliar player will thus approach to investigate ) and detonate shortly thereafter with a fair amount of force . This will tend to leave most players wary of baby carriages in the future , despite the rather limited distribution of the trap . It requires explosives skill of 60 to disarm , and unlike most explosive traps its frag mines cannot be salvaged . Once disarmed , it can be rearmed as a time bomb , or a proximity bomb . This trap can also be grabbed and moved to a more useful position before re - arming . The bomb explodes when shot , providing an easy removal for characters with low explosives skill . This trap can be found in the Meresti service tunnel and Hubris Comics . Rigged mailbox . Similar to the baby carriage , the rigged mailbox is an ordinary pre - War mailbox rigged to explode if anything ventures too close . If disarmed ( with an Explosive skill of 45 ) , the explosive is added to the player ' s inventory . It can then be rearmed on either a timer or a proximity fuse . All rigged mailboxes have a small metallic antenna poking out of the top of some part of the letter receptacle , which helps in distinguishing them in good lighting conditions . You can find some just to the south of the raid shack . Only small mailboxes in front of houses can be found with this trap , thus such trap is quite rare . Large blue US Post Office boxes can not be rigged to explode . Rigged terminal . Another variation on the deadly ordinary objects theme , rigged computer terminals can be found in certain locations . Attempting to use the terminal triggers the trap , causing a slight electrical shock followed by detonation of the main frag grenade inside . It can be recognized by the antenna on the back and the warped rear panel . The trap can be deactivated by defusing the back panel . Disarming the trap will move the grenade into the player ' s inventory . The terminal can then be rearmed in the same fashion as the previous two examples . An example of this trap can be found in the drainage chamber near Jocko ' s Pop & Gas Stop ( the source of Signal Sierra Victor ) or near the entrance to Pinkerton ' s hideout in Rivet City . Note that the terminal is just a trap and does not actually contain an interface ; attempting to use it after it is disarmed only displays a dialog box explaining that it must be rearmed to function , which must be done using the rear panel . Toilet trap . The toilet trap is a simple electrical trap designed to shock anyone who decides to use the toilet ( to drink from , in the player ' s case ) , and can be disarmed by standing on the bowl of the toilet and removing the microfusion cell s from the tank . 35 microfusion cells are in the tank which provide the charge , and are added to the player ' s inventory if the trap is disarmed . Two wires leading from the tank to the bowl indicate a rigged toilet , and they disappear once the trap is disarmed . One example of this trap is found in the Tenleytown / Friendship station ' s bathroom nearest the Chevy Chase North exit . A skeleton lying near the bowl serves to warn the player of the danger . Others can be found in the Robot Repair Center , The National Archives , the Museum of Technology , and in the Statesman Hotel . Firing mechanisms and initiating actions . Trip wire . Trip wires are thin , easily broken wires suspended a few inches off the floor , usually just behind doors so players won ' t see the posts it is tied to . Opening the door doesn ' t trigger it . Players with the Light Step perk can walk over them without fear . They require a repair skill of 25 to disarm . The player must interact with the posts to disarm it , as the wire is intangible . Laser trip wire . Found only in Raven Rock , laser trip wires function by detecting when the beam is interrupted , and respond after a one - second delay with a puff of flammable gas , and a burst of flame to ignite it . The tripwire itself is not a weapons - grade laser beam and will not deal damage nor ignite the gas . The laser tripwire emitter can be disarmed with a repair skill of 85 or a science skill of 67 . Pressure plate . Pressure plates are weight - activated mechanisms set off when it senses pressure from the player stepping on it , thus triggering the associated trap , a common example is rigged shotgun . Bear traps have built in pressure plates . The Light Step perk will allow players to avoid triggering either variety . Pressure plates require a repair skill of 25 to disarm . The bear trap version can be triggered with a direct gunshot or an object . Proximity fuse . All mines , including the rigged mailbox and baby carriage , work on a proximity fuse . The Light Step perk will negate ordinary mine fuses but not the fuses of rigged carriages or mailboxes . Thus , the choice comes down to attempting to disarm the explosive before it detonates , simply avoiding it , or to fire directly upon it with a gun or explosive of your own ( preferably at a safe distance , of course ) . Usage . Rigged equipment such as computer terminals are triggered by any attempt to use them . A separate area on the object must be interacted with to disarm it . Remote detonator . The Preacher in Seward Square apparently sets off his minefield remotely . Mines can also be detonated remotely by shooting them , as Arkansas in Minefield is scripted to do . Video . YouTube video about House of Traps in " Fallout 3 " : YouTube " Fallout 3 " Domino Trap