About Rating Caves

Rating Caves

By: Eric Pelkey

I am an engineer. As an engineer, I like to quantify natural phenomena and try to package them into a useable form of numerically comparative data. I also enjoy rock climbing; when I go rock climbing, I can always get an idea of what climbs I should try in a given area based on a rating system which has developed over the years. When I first began caving, I was a little bit surprised that there was no similar system for caves. As I began caving in a diverse caving community, one which went on trips which varied widely in difficulty, I found it was difficult to get a bearing on descriptions which were given to me. That is to say, how many times have you asked about a trip only to be told “It’s really muddy, and there will be some crawling?”  Anyone who has caved with different caving groups and has received this description knows that that it could mean a barely dirty trip with a short stoop walk or an hour of slithering through peanut buttery mud. This is clearly a challenge waiting to be solved.

To help provide a uniform rating of caves, I decided that a standard was needed and that I would try my hand at making it. Because caves can be challenging in different ways (imagine endless crawls, soupy mud, or long drops) a categorized rating system is required. I also realized that especially in larger cave systems you can find many of the challenges above, but they may have no bearing on the trip you were interested in (i.e. Mammoth Cave has deep water in some sections, but that does not mean tourists on the trails need wetsuits). For this reason, my cave rating system is actually a cave trip rating system. There are many trip possibilities, even within the same cave; so, the specific trip should be specified with the cave name. This standardized trip rating system can assist trip leaders in selecting trip participants, and it can help cavers select which trips interest them. This system is especially useful for cavers new to a caving group or area and would greatly improve the efficacy of trip sign-ups at caving events.

To make my system, I began by identifying the principal challenges of a cave trip. I settled on seven principal challenges broken into five difficulty levels. The challenges used in this system are verticality, tight passage (either crawlway or tight sinuous canyons), water, mud, smallest squeeze, free climbing, and trip length. By building a characteristic string of seven scores for each trip, cavers can glean a concise standardized assessment of what skills and equipment they should need for a trip. I further developed a method to reduce these scores to one number, quantifying the challenge of the trip, by adding the first six categories together and multiplying by the seventh. It is important to note that by doing this a lot of the coded information and usefulness of the system is lost. That is to say the number is a supplement to the code and is not intended to be the sole take-away from the rating system. These ratings are all based on “normal” cave conditions (i.e. if it is a flood prone cave, the wetness level would be for average caving conditions and not when the cave is sumped shut). The trip length scores are round-trip travel time for a small group of experienced “average” cavers. Extended resting periods, including cave camps, and time spent partaking in non-travel activities should not be included in the calculation of travel time. Additionally, some adjustment to time calculations may be necessary if a group is particularly fast or slow. Obviously, subjectivity in rating systems cannot be completely removed; so caves trips, like rock climbs, will benefit from many different people rating to come to a consensus grade. So, go ahead, rate your trips and add your ratings!

Table Explaining Each Difficulty Level of the Seven Categories

Verticality
1	Horizontal caving trip (no rope encountered)
2	Safety traverse lines or cable ladders only
3	Free hanging drops of short to moderate length (<100ft span="">
4	Rebelays or longer drops (>100 feet) or between 5 and 10 pitches
5	Advanced vertical- >300ft in 1 pitch or 500 ft total, J hangs, very wet, or tight, or >10 pitches
Crawl/Crevice
A	Walking/stooping passage
B	Some hands and knees crawling , very brief belly crawls, or periods short easy chimneys
C	Moderate (100-500ft) hands and knees, (50-100ft belly), or moderate periods (<100ft canyons="" exposure="" low="" of="" span="">
D	Long crawls mostly low belly crawls, or longer canyons requiring some climbing skill
E	Seemingly endless belly crawls/crevices with complications (steep, floorless, etc)
Water
p	Dry Cave
q	Light dripping cave streams which remain below ankle
r	Heavy dripping or wading up to waist high or shallow stream crawl
s	Periods of full chest immersion
t	Full or partial head immersion (ear dips, free dives, heavy waterfalls
Mud
i	No mud (dusty , sandy, or bedrock)
ii	Some cave sediment, tends not to stick
iii	Muddy cave, mud sticks in many places
iv	Very Muddy "We are all brown in the cave"
v	Consistently sloppy coating "My gear now weighs twice as much"
Squeeze
.1	No squeezes (anyone will fit)
.2	1.5’
.3	1’
.4	8”
.5	6”
Free Climbing
v	None
w	Some steep slopes which require hands use
x	Vertical climbs with many holds and little exposure
y	Exposed climbs requiring some skill
z	Difficult scary climbs
Distance (round trip travel time)
X1	<2hrs span="">
X2	2-5hrs
X3	5-9hrs
X4	9-14hrs
X5	>14hrs