Electricity
Exposure to electricty can have greatly varied effects, depending on the voltage, current, frequency, waveform, and duration.
Mechanically, a difference in voltage between two locations is what drives an electric current between those locations; if two parts of your body are in electrical contact with regions of different voltage, it is the electric current flowing through your body between these two points that causes damage.
Consequently, to be affected by electricity, you must be touching two (or more) electrical contacts with different voltages.
In many cases, one of these contacts can be the ground; but if you are isolated from the ground then just touching one high voltage contact will not do anything to you.
Electricity will take the easiest path between to get between different voltages. If it can flow down a conductor instead of through meat, it will do so.
Consequently, shorting the gap between the contacts with something highly conductive, allowing the electric current to flow around you along the conductor, will protect you.
This is the principle behind lightning rods and Faraday cages (a metal enclosure that screens what is inside from damaging electrical effects).
As an example, wearing a suit of chain mail can protect you against more than just swords and arrows!
At worst, touching a live wire while wearing a mail suit with skin-to-skin contact will result in the electricity flowing through your hand to the metal sleeve, traveling along the mail hauberk to the hem, and then jumping back to your leg to flow out of your body to ground. In this way, the current will bypass your vital organs.
If you had a gauntlet on your hand and chain dangling from the hem and dragging on the ground, you would be entirely protected even without skin-to-skin contact.
A common form of electrical safety gear is a simple loop of grounded wire worn on the wrist like a bracelet – touching an energized electrical contact with your hand then only results in current flowing through your hand, not your body.
Voltage is the driving force of electricity. The more voltage, the better it can get through stuff.
Penetration is 1 for every 7500 V. This gives its ability to arc across gaps and through insulators. Figure that a known air gap gives a flat Armor Value of 1 for every 2.5 mm in length – subtract the Armor Value of an air gap directly from the Penetration.
More usually, distances are uncertain and the Armor Score (the RS of the 2d6 armor roll) is -2 + score of [typical gap distance in cm].
If the Armor Value equals or exceeds the Penetration, the voltage is not high enough to initiate dielectric breakdown and no arc occurs.
Otherwise, the electricity arcs between the high and low voltage contacts, causing full effect to anyone caught in the arc. Armor or air gaps that are arced through or across give no subsequent protection once the arc is formed.
Electricity sources with low Penetration will not arc appreciably, requiring direct contact with both high and low voltage to have an effect.
If the electricity cannot arc through intervening material, it might be able to flow through it (called conduction).
The resistance of the material to electric flow will reduce its Dose and damage Point RS to its victims.
Light clothing will decrease the Dose and Damage Point RS down by 1, normal footwear or moderate clothes by 2.
Actual protective gear such as electrial gloves, footwear, or mats in good repair will block all non-penetrating electricity.
Below is a list of some of the effects electricity can have:
Nervous shock:
An electric current can cause nerves to fire, or simulate the electrical effects of nerves firing on muscles. This will discombomulate and confuse the physiological mechanisms that make the body work.
This can result in the pain and tingling of an electric shock, or more serious conditions such as heart arhythmias, heart fibriliation, a stopped heart, and arrested breathing.
In game terms, an electric shock can be simulated with a Penetration that increases with voltage, resulting in neural stun if it penetrates any insulation. For arcing electricity, this Penetration is just a carrier for the main effect, if it gets through any insulating layers to the person underneath the victim will be subject to the full Dose. Non-arcing sources have the Dose reduced by the RS by which insulation "armor" reduced the Pen.
While the electric current inflicts neural stun, it will have additional symptoms beyond those of the usual neural stun:
- Most electrical wave forms will kill if the electric Fatigue reaches the mild shock level, through effects on the heart or stopping breathing.
If the current path passes through the chest (or wherever your species keeps its heart(s) and lung(s)), the victim must succeed a DC 4 Vigor check or suffer cardiopulminary failure.
The DC increases by 2 for every additional Fatigue increment beyond mild shock.
This effect is absent in electrical sources specifically engineered to shock but not kill.
- Many electrical sources can cause the victim's muscles to contract so violently that she injures herself.
At the first Fatigue increment and beyond, shock from these electric sources will cause the victim to deliver her own unarmed damage to herself on each of her actions, for so long as she is exposed to the current.
This damage is at +½ RS for each additional Fatigue increment, up to +3½.
In addition, on the first exposure the victim's muscular contractions cause her to jump backwards to her full jumping distance (as if using extra effort at 2+ Fatigue increments, and maximum extra effort at 3+ Fatigue increments), and then fall down.
If she strikes a solid object in the process, she again takes her unarmed damage (with the same increase to RS) as if from a grappling smash.
This effect is absent in electrical sources specifically engineered to shock but not kill.
- AC current will cause the victim to involuntarily clench their hands. If the victim was exposed to the electricity by grabbing the electrical contact, she will keep holding on with all her strength.
This will continue expose her to electricity on subsequent rounds unless the electricty source can be shut off or she is forcibly removed from the contact.
To free a victim requires winning a Contest of Strength against her, using her full Strength unpenalized by shock penalties – and with the same increase to Brawn from extra effort as for the knockback jump described in the previous bullet.
However, see the note on Rescuing Victims, below.
If she tries to free herself, she must win such a Strength contest with herself, but her voluntary Strength check is penalized by the shock penalties.
On the first round of exposure, the Strength of the knockback jump will contest this clenching reaction to break free (unless the gripped electrical contact can move far enough back with the jump), but thereafter it does not apply.
Body parts (head, torso, limbs) are considered to be "hit" if they are in the current path through the body.
Very high frequency electric currents, such as those produced by Tesla coils, do not cause nervous shock (and thus will not cause mechanical injury, either). They can, however, cause electrical burns.
Electrical burns:
High voltage and high current electrical sources will dissipate power along the current path. If this power is enough to heat up living tissue past the point where proteins begin to denature, it will cause electrical burns.
These burns are usually internal, with the only external evidence skin burns at the point of entrance and exit.
Electricity that can cause burns will directly inflict damage points. Roll 2d6 and apply the listed RS to determine the damage points and the resulting wound level. The current will cause a separate injury to every hit location along the current path. This injury is always penetrating.
Arc flash:
Arc flash is a potential hazard around high power and high voltage equipment, such as power generation or distribution equipment, or some high power industrial processes.
A high power electrical arc can produce intense radiant heat, enough to cause severe burns to those nearby.
When the arc is struck, it will produce a dazzlingly brilliant blue-white flash.
If the arc discharge does not immediately vaporize the electrial equipment, and if it not stopped by protective equipment such as breakers, the arc may be sustained, allowing the arc flash effect to continue for many combat rounds.
Those nearby will be affected by a pulse causing burn damage.
Arc flashes are often associated with arc blasts.
Arc blast:
When high power electric current strikes an arc and vaporizes some of the material it is flowing through, the supersonic expansion of the vapor and debris causes an explosive blast delivering concussive force and throwing shrapnel.
Rescuing victims:
When you see someone, especially a friend of yours, being electrocuted, it is only natural to grab them in order to separate them from electrical contact.
Unfortunately, this makes you part of the circuit as well.
If you do this without insulation, you take the same damage if the electric circuit can complete through your body. For example, if the electricity is flowing from an energized wire to ground through your buddy, and you grab your buddy, the electric current will pass from your buddy through your hands and arms down your torso and through your legs and feet to ground.
In such cases, it is best to de-energize the electrical contact instead of grabbing and pulling.
If that is not possible, use something insulated to pull the victim away, such as a belt, a heavy jacket, or a cord.
If the victim is involuntarily holding on due to muscle contractions, you will need to win a contest of Strength with the victim in order to pull them free, and the victim's Strength is not penalized for this purpose by the effects of the shock.
For those shocked into cardiopulminary failure, a Smarts + Heal skill + victim's Vigor check can resuscitate the victim, restoring vital functions.
This uses the same DC as the victim's initial Vigor roll to avoid cardiopulminary failure.
Would-be rescuers get one chance at resuscitation.
If this fails, an additional DC 7 Smarts + Heal skill + victim's Vigor task every 10 minutes allows CPR to keep the victim's brain tissue alive from artificial mechanical action of the chest, which can potentially save the victim if he can be brought to a hospital in time.
Success by 5 or more on this task will revive the victim, on a failure the victim dies (but the would-be rescuer will not necessarily know this – after all, breathing and pulse has already stopped and the victim is unconscious).
Applying chest compression through CPR causes damage as a 2-handed unarmed attack (i.e. +1 RS to Pen) for every check – CPR may keep you alive, but you are likely to be left with cracked ribs and nasty bruises.
Defibrilator equipment allows a second resuscitation attempt, allowing the victim a DC 7 check against their Vigor to restart their heart and breathing.
Electricity Sources
Lightning:
Lightning is one of the most dramatic natural phenomena. The voltages and currents produced are extreme by any measure compared to anything people can make, capable of arcing through kilometers of air and heating a plasma channel to far hotter than the surface of the sun.
This makes lightning strikes very dangerous.
Fortunately, a couple factors contribute to make lightning strikes not insta-death to everyone affected. First, the lightning flash generally only lasts a fraction of a second, which limits the current delivered and the searing radiant intensity from the brilliant arc.
Second, the bolt tends to flash over the surface of organic beings rather than going through them, so that people directly struck do not suffer the full force of the discharge.
Enough current does leak through to pose a significant hazard, but at least victims are not exploded across the landscape.
In fact, most people harmed or killed by lightning are not struck directly.
Much of the risk comes from the currents that lightning can produce in the surrounding environment, with currents flowing through the ground across the strong drop in potential radiating away from the point of contact.
Those standing on the ground will have electrical contact at their feet, and the difference in voltage between them will drive currents up one leg and back down the other.
In addition, if a person is touching a conductive object and the ground when lightning strikes that object, that person becomes part of the circuit and can be electrocuted.
Lightning bolts vary considerably in their voltage, current, and duration. To reflect this, roll 2d6 + 3 for the Energy Score of natural lightning strikes.
There are several ways a person can be affected by a lightning strike:
- On a direct hit, the lightning bolt touches the victim's body.
A lightning strike usually connects near the victim's highest spot – for standing humans, roll 1d4 for the entry hit location (with arm hits respresenting strikes to the shoulders) and the exit hit location will be the feet.
Victims of a direct hit suffer flash burns in addition to the full effects of shock and electrical burns, undiluted by distance.
- A splash exposure occurs when the victim is exposed to the transient fields around the lightning bolt. This can occur when the victim is standing on the ground near the point where the bolt strikes, and the powerful ground currents are also conducted through the victim, or if the victim is in the water near the strike location.
Splash hits cause shock and electrical burns, but these are reduced in effect with increasing distance from the strike.
Bipeds like humans have a geometry that is more resistant to the effects of ground current – if they are only standing on their two feet.
A standing biped reduces the Dose from ground current by 2, or by 4 if they are standind on only one foot or deliberately standing (or crouching) with their feet as close together as possible. In addition, most of the current that goes through a standing biped will just go up one leg and down the other so relatively little of it will pass through the vital organs of the torso – give these victims a +3 to checks to avoid cardiopulminary failure.
Water is highly conductive. Victims of splash damage who are in water suffer a +3 to Dose (but never more than the Dose for a direct hit).
- Contact exposure occurs when the victim is touching a conductor that was struck by lighting. The victims take the full shock and electrical burn damage un-diluted by distance if the victim offers a path to ground from the conductor. If the conductor itself shorts the path to ground, reduce the Dose by 5.
In addition, there are several different effects of lightning strikes:
- Shock: Victims in the direct line of a lightning strike or touching a lightning-energized conductive object will take a Dose equal to the Energy Score.
Ground current will cause a Dose of the Energy Score + (victim's Size - range score), but never more than the Energy Score.
- Electrical Burns: Internal electrical burns are occasionally an issue. The damage RS is the Energy Score - 16 + 2 × victim's Size for internal lightning electrical burns.
- Arc Burns:
Victims of a direct strike always take their full Penetration Limit of Pen to every body part in the current path as the lightning arcs down across their entire body.
Fortunately, since the lightning flashes over the victim's surface, this injury is non-penetrating.
Assess burn damage with a Wound of +0.
- Arc Blast: The concussive blast of a lightning strike will have a Brawn of Energy Score - 10 at a distance of 1 meter. Unlike blasts from point sources expanding out as spheres, blasts from columnar sources like lightning fall off as -2 RS times the range score from the bolt to the victim.
- Arc Flash:
Powerful lightning strikes can cause radiant burns out to some distance. Those with an Energy score of 13 or more have a Pen of value of [Energy Score - 20] at a distance of 1 meter. Unlike pulses from point sources, the pulse from a columnar source like a lightning bolt falls off as -1 RS times the range score from the bolt to the victim.
Electrical equipment:
Many items of electrical equipment are too low voltage or too low power to cause any harm.
Those items that require hazardous voltages and higher power will almost always have the energized electrical contacts out of reach behind panels and insulated casings, with any exterior conductive surface properly grounded (one-off prototypes made by not-so-competent garage engineers may be an exception).
Any device which is de-energized – the cord unplugged from the wall, internal power sources removed, and large capacitors shorted – will pose no hazard.
Anyone who is poking around inside an energized device with hazardous levels of electricity must succeed a task of Smarts + appropriate Fix and Build skill with a DC of 1. Experimental or specialized equipment may have an increased DC.
Familiarity with the particular device applies.
Failure results in electrical contact.
In addition, failure by sufficient margin on any Fix and Build checks may leave the device in an unsafe state, resulting in a shock or fire hazard when the device is re-energized.
Dropping an appliance in water can result in electrical contact with those in contact with the water.
Use the rules for lightning splash exposure water strikes, replacing the lightning Dose with the shock Dose for the appliance.
A ground fault circuit interrupter (GCFI) on the outlet or plug, or internal to the device, will stop the electricty before it can cause a shock in the event that someone makes simultaneous electrical contact between the energized parts of the device and the ground. This includes potential shocks from contact with water.
It will not protect those who contact both the hot and return wires – but this involves deliberately opening the device up and messing with its wiring.
The electrical hazards examples table gives a number of sample pieces of electrical equipment and their effects on electrical contact.
- The Domestic Appliance line is for things like hair dryers, toasters, and power tools. In modern times, these would be powered by a cord connecting to the household wiring but in futuristic settings like Vergeworlds they may be powered by electrical energy storage cells.
- Large appliances are things like clothes dryers. In the U.S. they run on 220 V wiring rather than 110.
- HV industrial equipment is for heavy duty devices, usually running on 480 V. These are not found in typical houses, but can be found in factories, foundries, and other industrial settings.