Environmental Hazards

Temperature Ratings
Temperatures rate from 1 to 10, representing variations in temperature in the environment. Temperature Rating 1 ranges from Absolute Zero to -199 Fahrenheit. Temperature Rating 2 represents temperatures from -200 to -21 Fahrenheit. Temperature Rating 3 Represents -20 to -1 Degrees Fahrenheit. Temperature Rating 4 ranges from 0 to 39 degrees Fahrenheit. Temperature Rating 5 ranges from 40 to 90 Degrees Fahrenheit. Temperature rating 6 ranges from 91 to 110 degrees Fahrenheit. Temperature 7 ranges from 111 to 140 degrees Fahrenheit. Temperature Rating 8 ranges from 141 to 300 degrees Fahrenheit. Temperature Rating 9 ranges from 301 to 700 degrees. Temperature Rating 10 ranges from 701 and up degrees Fahrenheit.

When creatures are exposed to environments six or more Temperature Ratings lower, they take 5d6 points of lethal damage per minute (no save). In addition, a character must make a Fortitude save (DC 25, +1 per previous check) every round or take 2d4 points of nonlethal damage.

When creatures are exposed to environments five Temperature Ratings lower, they take 3d6 points of lethal damage per minute (no save). In addition, a character must make a Fortitude save (DC 15, +1 per previous check) every round or take 2d4 points of nonlethal damage.

When creatures are exposed to environments four Temperature Ratings lower, they take 2d6 points of lethal damage per minute (no save). In addition, a character must make a Fortitude save (DC 15, +1 per previous check) or take 2d4 points of nonlethal damage.

When creatures are exposed to environments three Temperature Ratings lower, they take 1d6 points of lethal damage per minute (no save). In addition, a character must make a Fortitude save (DC 15, +1 per previous check) or take 1d4 points of nonlethal damage.

When creatures are exposed to environments two Temperature Ratings lower, they must make a Fortitudesave once every 10 minutes (DC 15, +1 per previous check), taking 1d6 points of nonlethal damage on each failed save. A character who has the Survival skill may receive a bonus on this saving throw and might be able to apply this bonus to other characters as well. Characters wearing a cold weather outfit only need check once per hour for cold and exposure damage.

When creatures are exposed to environments one Temperature Rating lower, they must make a Fortitude save each hour (DC 15, +1 per previous check) or take 1d6 points of nonlethal damage. A character who has the Survival skill may receive a bonus on this saving throw and might be able to apply this bonus to other characters as well (see the skill description).

When creatures are exposed to environments one Temperature Rating higher, they must make a Fortitude saving throw each hour (DC 15, +1 for each previous check) or take 1d4 points of nonlethal damage. Characters wearing heavy clothing or non-environmental armor of any sort take a –4 penalty on their saves. A character with the Survival skill may receive a bonus on this saving throw and might be able to apply this bonus to other characters as well (see the skill description). Characters reduced to unconsciousness begin taking lethal damage (1d4 points per hour).

When creatures are exposed to environments two Temperature Ratings higher, they must make a Fortitude save once every 10 minutes (DC 15, +1 for each previous check) or take 1d4 points of nonlethal damage. Characters wearing heavy clothing or non-environmental armor of any sort take a –4 penalty on their saves. A character with the Survival skill may receive a bonus on this saving throw and might be able to apply this bonus to other characters as well (see the Survival skill in Using Skills). Characters reduced to unconsciousness begin taking lethal damage (1d4 points per each 10-minute period).

When creatures are exposed to environments three Temperature Ratings higher, they suffer lethal damage. Breathing air in these temperatures deals 1d6 points of fire damage per minute (no save). In addition, a character must make a Fortitude save every 5 minutes (DC 15, +1 per previous check) or take 1d4 points of nonlethal damage. Those wearing heavy clothing or any sort of non-environmental armor take a –4 penalty on their saves. In addition, boiling water does a d6 of damage per round of exposure, unless they are immersed in it. In this case it does 10d6 damage per round of exposure.

When creatures are exposed to environments four Temperature Ratings higher, they take even more damage. The damage per minute increases to 2d6 points of fire damage per minute (no save). In addition, a character must make a Fortitude save every minute (DC 15, +1 per previous check) or take 2d4 points of nonlethal damage. Those wearing heavy clothing or any sort of non-environmental armor take a –4 penalty on their saves.

When creatures are exposed to environments five Temperature Ratings higher, they damage increases even further. The damage per minute increases to 3d6 points of fire damage per minute (no save). In addition, a character must make a Fortitude save every round (DC 15, +1 per previous check) or take 2d4 points of nonlethal damage. Those wearing heavy clothing or any sort of non-environmental armor take a –4 penalty on their saves.

When creatures are exposed to environments six or more Temperature Ratings higher, they suffer 5d6 points of fire damage per minute (no save). In addition, a character must make a Fortitude save every round (DC 25, +1 per previous check) or take 2d4 points of nonlethal damage. Those wearing heavy clothing or any sort of non-environmental armor take a –4 penalty on their saves.

Creatures and their Temperature Ratings
Most humanoid species of Rifts Earth are considered Temperature Rating 5. Some creatures born in harsher climates are still Temperature Rating 5, but have protection that allow them to ignore a single TR shift in a single direction, such as Arctic Barbarians, who can survive in temperatures approaching 0 degrees with no protection. This usually comes with difficulty on the other end. See the “Temperature Acclimation” feat for more information.

Pressure Rating
Pressure ratings determine what kind of pressure environments creatures can survive without harm or preparation. Intense pressure and a lack of pressure can both be severely dangerous climates for creatures.

Pressure Rating 1 ranges from 160 to 80 tons/square foot (5k-2.5k ft below surface of ocean). Pressure Rating 2 ranges from 80 to 25 tons/square foot (2.5k-785 ft below surface of ocean). Pressure Rating 3 ranges from 25 to 10 tons/square foot (785-300 ft below surface of the ocean). Pressure Rating 4 ranges from 10 to 3 tons/square foot (300-100 ft below surface of the ocean). Pressure Rating 5 ranges from 3 to .75 tons/square foot (100 ft below surface of the ocean to 5 miles above the Earth's surface). Pressure Rating 6 ranges from 1,500 lbs/square foot to 500 lbs/square foot (5 miles above the Earth's Surface to 8 miles above the Earth's Surface). Pressure Rating 7 ranges from 500 lbs/square foot to 50 lbs/square foot. This is known as a “Vacuum.” Pressure Rating 8 ranges from 50 lbs/square foot to 0 lbs/square foot. This is known as an “Absolute Vacuum.”

When creatures are exposed to environments four Pressure Ratings lower than they are rated for must make Fortitude save (DC 25+1 per previous check) every minute or take a 2d4 of non-lethal Pressure damage. They also take a 2d6 of lethal Pressure damage. Objects must make similar saves, taking 2d4 Pressure damage that ignores hardness and DR.

When creatures are exposed to environments three Pressure Ratings lower than they are rated for must make Fortitude save (DC 15+1 per previous check) every minute or take a d4 of non-lethal Pressure damage. They also take a d4 of lethal Pressure damage. Objects must make similar saves, taking d4 Pressure damage that ignores hardness and DR.

When creatures are exposed to environments two Pressure Ratings lower than they are rated for must make Fortitude save (DC 15+1 per previous check) every 10 minutes or take a d4 of non-lethal Pressure damage. Objects must make similar saves, taking a single point of Pressure damage that ignores hardness and DR.

When creatures are exposed to environments one Pressure Rating lower than they are rated for must make Fortitude save (DC 15+1 per previous check) every hour or take a d4 of non-lethal Pressure damage.

When creatures are exposed to environments one Pressure Rating higher, than they suffer a -2 to all Constitution checks. This includes Fortitude saves, stabilization checks, saves against heat/cold, saves to maintain a run, etc. In addition, they must make a Fortitude save (DC10+1 per previous check) every ten minutes or take a single point of non-lethal damage.

When creatures are exposed to environments two Pressure Ratings higher, they suffer a -5 to all Constitution checks. In addition, they must make a Fortitude save (DC15+1 per previous check) every minute or take a d4 of non-lethal damage.

When creatures are exposed to environments three Pressure Ratings higher, they suffer a -8 to all Constitution checks. In addition, they must make a Fortitude save (DC15+1 per previous check) every round or take d8 non-lethal damage.

Exceptions to these rules are for a Vacuum and an Absolute Vacuum. When creatures rated for ANYTHING other than one of these two Pressure Ratings, they follow the rules below.

In a Vacuum, creatures rated for Pressure Ratings one through six suffer a d6 of Pressure damage per round. Normally, Vacuums also do not provide enough air to breathe in, and suffocation rules apply as normal (unless the creature does not need to breathe or is rated for low atmosphere). Creatures rated for an Absolute Vacuum (Pressure Rating 8) are affected as normal (See “Environments one Pressure Rating Less).

In an Absolute Vacuum, creatures rated for Pressure Ratings one through six take a d6 of MORTAL damage per round. Absolute Vacuums do not provide enough air to breathe in, and suffocation rules apply as normal. Creatures rated for Pressure Rating 7 are affected as if they as normal (See Environments one Pressure Rating higher).

Creature's and their Pressure Ratings
Most creatures on Rifts Earth have Pressure Rating 5. Some feats and training can augment a character's Pressure Rating. Deep sea creatures can often function at much higher Pressure Ratings, while some objects are designed to avoid the stresses from high pressure environments. Objects do not take damage from low-pressure (Higher Pressure Ratings) environments, only environments with higher pressure (Lower Pressure Ratings) than they are rated for.

Gravity
When functioning in variable gravity, a number will be presented. This is usually a number listed to describe just how much gravity has been augmented and how it affects the environment. Jumping and thrown/projectile weapon distances are divided by this number (though range increments are unchanged). For example, in 1/6th gravity (such as the moon), a DC 20 running long jump would clear a whopping total of 120 feet, while a character in double gravity can only jump 10 ft with a DC 20 jump check.

In addition, most checks are negatively affected by gravity differing from a creature's normal gravity. Gravity that exceeds 3/4 to 1 ¼ their native gravity will begin negatively affecting character's abilities. In gravity between 1/2 to 3/4 of their native gravity, melee attacks do damage as if their Strength was 4 points less (to a minimum of 2). In gravity between ¼ and ½, their melee attacks do damage as if their Strength was 6 points less (to a minimum of 2), and attacks made in gravity less than ¼ their native gravity will do damage as if their Strength was 8 points less (to a minimum of 2). This penalty represents the overall difficult of maneuvering in low-gravity environments. The difficulty makes it difficult to line up solid strikes. However, certain feats and abilities can limit this penalty.

In gravity 1 ¼ to 1 ½ times stronger, melee attacks are not negatively or positively affected (since any maneuverability penalty would be negated on both fronts), but combat and other rigorous activity is far more strenuous. In the higher gravity above, characters take 1 point of non-lethal damage every round of difficult activity they engage in. This includes running, fighting, riding a horse, spell-casting, etc.

In gravity 1 ½ to 1 ¾ stronger, they take d4 points of non-lethal damage for strenuous activity, a d4 of non-lethal every hour (DC 15+1 per previous check negates), and must make a DC10 Strength Check every hour to move normally. Failure leaves the character moving at ½ their speed and suffer a -5 penalty to all checks requiring complicated movement.

In gravity 1 ¾ to 2 ½ times stronger, non-lethal damage increases to d6 per round of strenuous activity, and a d6 of non-lethal every hour (DC 20+1 per previous check), the Strength Check increases to DC 15, the penalties increase to -10, and movement speed is reduced to ¼ their speed. The strength check must be made every minute.

In environments 2 ½ to 3 times stronger, the non-lethal for strenuous activity increases to d8 per round, and they must make fortitude saves (DC20+1 per previous check) against a d6 of hit-point damage every 30 minutes. Failing the Strength DC now results in being completely immobile and flat against the ground, and the check must be made every round.

In environments more than 3 times stronger, they take d10 non-lethal damage per round and must make saves (DC20+1 per previous check) or take 2d6 of hit-point damage every minute. Succeeding on the Strength check (DC 25) will allow a character to crawl five ft per round and perform simple maneuvers, but lifting ones arm more than a few inches requires another Strength check, and lifting one's body requires another one at DC 35.

The combination of high gravity, high pressure environments (such as low points in the ocean of huge worlds) can result in almost instantaneous death, while low pressure, low gravity environments are more of a nuisance than anything. It is incredibly difficult, expensive, and dangerous to design machines that can function in high pressure environments, and high gravity is almost impossible to counteract unless one has access to incredibly powerful, gravity-negating magics or technology.

Low pressure and low gravity environments can be negated with training, a sealed environment suit, and some sort of a propulsion system. As mentioned above, some feats and skill checks can also limit the negative effects of lower gravity.

Zero Gravity (which includes the range of 1/10th to Zero gravity), has slightly different rules. In this situation, normal movement speeds are no longer viable. Land, Swim, Climb, etc do not work, though Fly speeds can still work. Characters without a fly speed can move at ½ their highest other speed with a DC 15 Zero-G check. This is a difficult thing to do, however, since it can only be done if one can brace against a solid object with mass equal to or greater than the mass of the character attempting to move. They also can only move in a straight line, and will continue to do so until their inertia runs out or they hit another object. Failing this check by 5 or more causes the character to instead move in a direction 45 degrees away from their “target” direction, failing by 10 or more causes them to move 90 degrees, and failing by 15 or more causes them to move directly backwards (if possible).

In addition, in zero-g environments melee attacks do damage as if a character's strength score was 2. Certain feats can decrease this immense penalty, and characters grappling one another can use their grip on their foe to counterbalance themselves, allowing them to operate as if their strength was half their normal score, instead of at 2. Bite and squeeze attacks are completely immune to the effects of Zero-g, since the power of those abilities is based entirely on the user's body, not the environment. Rifts Earth creatures function normally at 1 Standard Gravitational Unit, or SGU.

Creature's accustomed to higher SGU, however, can take feats that augment their abilities. See the “Gravity Adjustment” feat for more information.