HT Rolls to Resist Cold - effects of a critical failure?

[Everett]

Oddly, GURPS Characters' cold rules don't include any information about what happens on a critical failure on a HT roll to resist cold. Considering that modifiers can add up rather quickly to the point that "failure by 10 or more" critical failures can become frequent, this seems to me to be a bit of an odd omission. (Such as a personal idea for "wind and very cold rain, perhaps with light clothing" - low windchills, wet clothing no matter what you do yet no risk of losing something to frostbite since the actual temperature is above freezing.)

It seems that either losing 2 FP or losing 1d FP are the most likely options - has there ever been an official answer on this?

Thanks.

(Also it seems that survival times in freezing water given for those assumed to be wearing lifejackets is (relatively) long; yet times for those not wearing lifejackets is given as very short, even (indirectly) the same source. IIRC rolling every 4 minutes instead of every minute seemed to produce the correct results for HT 10, don't remember if there were other rules, but I don't see why the same changes wouldn't apply to, say, a HT 12 Very Fit character without a lifejacket, since those don't provide any insulation.)

[Curmudgeon]

Originally Posted by Everett

Oddly, GURPS Characters' cold rules don't include any information about what happens on a critical failure on a HT roll to resist cold. Considering that modifiers can add up rather quickly to the point that "failure by 10 or more" critical failures can become frequent, this seems to me to be a bit of an odd omission. (Such as a personal idea for "wind and very cold rain, perhaps with light clothing" - low windchills, wet clothing no matter what you do yet no risk of losing something to frostbite since the actual temperature is above freezing.)

It seems that either losing 2 FP or losing 1d FP are the most likely options - has there ever been an official answer on this?

Thanks.

(Also it seems that survival times in freezing water given for those assumed to be wearing lifejackets is (relatively) long; yet times for those not wearing lifejackets is given as very short, even (indirectly) the same source. IIRC rolling every 4 minutes instead of every minute seemed to produce the correct results for HT 10, don't remember if there were other rules, but I don't see why the same changes wouldn't apply to, say, a HT 12 Very Fit character without a lifejacket, since those don't provide any insulation.)

No official answer that I'm aware of (which means nothing).

It isn't odd that there isn't any information about critical failures though. Resistance rolls are contests (B348), usually Quick Contests but sometimes Regular Contests. As a general rule, Contests take no notice of either critical successes or critical failures, usually taking notice only of Margin of Failure or Margin of Success, unless the specific rules (eg., Cold) indicate otherwise.

[Everett]

Originally Posted by Curmudgeon

No official answer that I'm aware of (which means nothing).

It isn't odd that there isn't any information about critical failures though. Resistance rolls are contests (B348), usually Quick Contests but sometimes Regular Contests. As a general rule, Contests take no notice of either critical successes or critical failures, usually taking notice only of Margin of Failure or Margin of Success, unless the specific rules (eg., Cold) indicate otherwise.

Had no idea. How would you recommend ramping up the rate of heat loss when you're rolling at -10? You could make failing by 10 or more 2 FP or 1d FP, , or failing by 5 or more 2 FP and 10 or more 1d FP?

[Pursuivant]

Originally Posted by Everett

Oddly, GURPS Characters' cold rules don't include any information about what happens on a critical failure on a HT roll to resist cold.

It is an odd omission and nothing in RAW, but then GURPS rules for Cold don't model hypothermia, frostbite, etc. that realistically.

I'd call it GM's choice, with a CF when dealing with general cold & windy weather above freezing resulting in 2 FP. First failure by 5+ or CF results in Moderate Pain (to model chilblains, shivering, and general debility associated with early hypothermia). The second failure by 5+ or CF results in Hallucinations (and the Delusion that you're actually uncomfortably hot, which leads you to shed clothes) and the third means Unconsciousness even if you're above 0 FP.

Below freezing, in addition to losing 2 FP, the GM can assess 1 HP x Margin of Failure (max. 1d-2 to 1d HP) of burn (cold) damage, distributed across exposed or wet body parts or a poorly-protected extremities, per High-Tech, p. 63.

Originally Posted by Everett

(Also it seems that survival times in freezing water given for those assumed to be wearing lifejackets is (relatively) long; yet times for those not wearing lifejackets is given as very short, even (indirectly) the same source.

Again, GURPS doesn't model cold injury very well. The rules for Thermal Shock were ported over from GURPS 3E rules discussing sudden immersion in Arctic water, with water temperatures at or below the freezing point of fresh water. Survival in "warmer" waters varies widely, but will ultimately be lethal unless (surface) water temperature is ~70 *F. (Warmer water can induce heat injury, but that's a different topic.)

Your rules fix is reasonably accurate for someone immersed in "cold but not freezing" water, like that of the North Atlantic or North Pacific, where survival time is less than 30 minutes. Perhaps increase the time increment for warmer waters.

[Fred Brackin]

Originally Posted by Pursuivant

I
Your rules fix is reasonably accurate for someone immersed in "cold but not freezing" water, like that of the North Atlantic or North Pacific, where survival time is less than 30 minutes. Perhaps increase the time increment for warmer waters.

WWII experience makes North Sea survival only 15 minutes even for fully suited aviators. In the Tropics it becomes indefinite. Sailors have survived 3 days in the water but by that time it's not hypothermia that's the problem.

[DouglasCole]

Originally Posted by Everett

Oddly, GURPS Characters' cold rules don't include any information about what happens on a critical failure on a HT roll to resist cold. Considering that modifiers can add up rather quickly to the point that "failure by 10 or more" critical failures can become frequent, this seems to me to be a bit of an odd omission. (Such as a personal idea for "wind and very cold rain, perhaps with light clothing" - low windchills, wet clothing no matter what you do yet no risk of losing something to frostbite since the actual temperature is above freezing.)

It seems that either losing 2 FP or losing 1d FP are the most likely options - has there ever been an official answer on this?

I'd not buy the entire book for two pages, but there are survival rules for hot and cold weather in my Citadel at Nordvorn and Hall of Judgment books. The suggestion I make for crit fail is that you take injury as well as fatigue, representing heat stroke, sunburn, and/or frostbite as needed.

[Pursuivant]

Originally Posted by Fred Brackin

WWII experience makes North Sea survival only 15 minutes even for fully suited aviators. In the Tropics it becomes indefinite. Sailors have survived 3 days in the water but by that time it's not hypothermia that's the problem.

Tables of expected survival times vs. water temperature are widely available, but not always accurate.

https://www.coldwatersafety.org/survival-estimates

There's also an online calculator with notional survival time calculations:

https://goodcalculators.com/cold-wat...me-calculator/

If you want detailed and depressingly realistic house rules:

Realistic Cold Water Survival Rules

Tweak survival times in different water temperatures as a multiple of the basic rules.

30-32 *F = roll every minute 1. When you first enter water, roll vs. HT to avoid physical Stun for MoF sec. CF means Heart Attack. Also make a Swimming skill roll to avoid inhaling water and beginning to Drown (due to Cold Water Gasp Reflex).
33-39 *F = 2 min. Roll for Immersion Shock, etc. as above.
40-49 *F = 4 min. Roll for Immersion Shock, etc. as above, but at +2 to HT and Swimming skill.
50-59 *F = 6 min.
60-65 *F = 8 min.
66-70 *F = 10 min.
71-75 *F = 20 min.
71-80 *F = 60 min.

Then apply modifiers for things like physical activity, wave action, partial insulation, and Size.

Modifiers: Modifiers for Size. Physically Active*, -1; Very Active* (e.g., swimming or treading water), -2; Rough Water, -1 to -4; Insulated Clothing or equivalent**, +1 to +10; Overweight, +1; Fat; +2; Very Fat, +4; Skinny, -2; Fit, +1; Very Fit, +2; Unfit, -1; Very Unfit, -2; Partial Immersion, +1 to +5.

* Treat as bonuses vs. cold when on land (+1 or +2, respectively).
** A waterproof barrier which encloses most of the body (such as a large trash bag) gives at least +1.

If wearing a lifejacket or similar flotation device a successful Swimming roll (assuming you avoid inhaling water) gives a further +1 bonus, +2 to Critical Success.

Temperature Tolerance (Cold) counts as a 5 *F water temperature increase per level. Amphibious or Aquatic creatures get full benefits.

Different Perks can give bonuses to HT & Swimming skills to survive in cold water.

Effects of Critical Failure to Resist Cold or Immersion Shock

1st CF = Shivering and reduced dexterity (-2 to DX & DX-based skills & Ham-Fisted 1 for fine manual tasks), 2 FP lost and 1 HP burn (cold) to an extremity due to frostbite if at or below freezing.

2nd CF = As above, but also Semi-Consciousness and reduced Will (-2 to IQ, Will, and skills based on those traits) and Reduced ST (-2 or -20%, whichever is worse). Physically active victims must make a Will roll to keep active rather than resting.

3rd CF = As above, but also Delusion (I'm too warm) for (20-HT) x 2 minutes, followed by Unconsciousness. Below 0 FP, victims take 1 HP x Margin of Failure burn (cold). At -HP and lower they must make death checks every minute.

[Everett]

Originally Posted by Pursuivant

Tables of expected survival times vs. water temperature are widely available, but not always accurate.

https://www.coldwatersafety.org/survival-estimates

There's also an online calculator with notional survival time calculations:

https://goodcalculators.com/cold-wat...me-calculator/

If you want detailed and depressingly realistic house rules:

Realistic Cold Water Survival Rules

Tweak survival times in different water temperatures as a multiple of the basic rules.

30-32 *F = roll every minute 1. When you first enter water, roll vs. HT to avoid physical Stun for MoF sec. CF means Heart Attack. Also make a Swimming skill roll to avoid inhaling water and beginning to Drown (due to Cold Water Gasp Reflex).
33-39 *F = 2 min. Roll for Immersion Shock, etc. as above.
40-49 *F = 4 min. Roll for Immersion Shock, etc. as above, but at +2 to HT and Swimming skill.
50-59 *F = 6 min.
60-65 *F = 8 min.
66-70 *F = 10 min.
71-75 *F = 20 min.
71-80 *F = 60 min.

Then apply modifiers for things like physical activity, wave action, partial insulation, and Size.

Modifiers: Modifiers for Size. Physically Active*, -1; Very Active* (e.g., swimming or treading water), -2; Rough Water, -1 to -4; Insulated Clothing or equivalent**, +1 to +10; Overweight, +1; Fat; +2; Very Fat, +4; Skinny, -2; Fit, +1; Very Fit, +2; Unfit, -1; Very Unfit, -2; Partial Immersion, +1 to +5.

* Treat as bonuses vs. cold when on land (+1 or +2, respectively).
** A waterproof barrier which encloses most of the body (such as a large trash bag) gives at least +1.

If wearing a lifejacket or similar flotation device a successful Swimming roll (assuming you avoid inhaling water) gives a further +1 bonus, +2 to Critical Success.

Temperature Tolerance (Cold) counts as a 5 *F water temperature increase per level. Amphibious or Aquatic creatures get full benefits.

Different Perks can give bonuses to HT & Swimming skills to survive in cold water.

Effects of Critical Failure to Resist Cold or Immersion Shock

1st CF = Shivering and reduced dexterity (-2 to DX & DX-based skills & Ham-Fisted 1 for fine manual tasks), 2 FP lost and 1 HP burn (cold) to an extremity due to frostbite if at or below freezing.

2nd CF = As above, but also Semi-Consciousness and reduced Will (-2 to IQ, Will, and skills based on those traits) and Reduced ST (-2 or -20%, whichever is worse). Physically active victims must make a Will roll to keep active rather than resting.

3rd CF = As above, but also Delusion (I'm too warm) for (20-HT) x 2 minutes, followed by Unconsciousness. Below 0 FP, victims take 1 HP x Margin of Failure burn (cold). At -HP and lower they must make death checks every minute.

Good rules! Question though - on land and in the water, what happens on a success and on an ordinary failure?

[Pursuivant]

Originally Posted by Everett

Good rules! Question though - on land and in the water, what happens on a success and on an ordinary failure?

For both immersion in cold water and exposure to Cold on land, you're making regular rolls for Cold just at faster intervals if you're in water or exposed to high winds. It's implied by the rules in the Basic Set that success means you don't lose FP, and by my rules that you don't lose FP, HP or suffer other ill effects.

Effects of a Critical Success are up to the GM but should represent some bit of luck which helps keep you alive a bit longer. Maybe double the normal time until the next roll or regain 1 FP.

[Everett]

Originally Posted by Pursuivant

For both immersion in cold water and exposure to Cold on land, you're making regular rolls for Cold just at faster intervals if you're in water or exposed to high winds. It's implied by the rules in the Basic Set that success means you don't lose FP, and by my rules that you don't lose FP, HP or suffer other ill effects.

Effects of a Critical Success are up to the GM but should represent some bit of luck which helps keep you alive a bit longer. Maybe double the normal time until the next roll or regain 1 FP.

Ah Okay. RAW has cold water as losing 1 FP on a success, and 1d FP on failure. (But not on land.) Question - what would be the "rough water" penalty if you're simply swimming underwater, maybe around 20-40 ft deep, in order to do something or get somewhere, as opposed to trying to stay on the surface to be rescued? From submarine experiences wave action stops pretty quickly a depth increases, so you might have calmer water but also be totally immersed.