'Considerable' rating

After two weekends of avalanche fatalities, I've now heard again the question of re-examining the use of a "considerable" rating in hind-site.  I was interested in seeing folks' thoughts here, in a specific conversation, separate from the news/condolences threads of specific accidents.

Personally, I'm having a very hard time accepting the notion that "Considerable" was/is not enough of a warning--almost to the point of feeling negatively judgmental towards a person who thinks that, and their ability to correctly make self-assessments and decisions in the BC (an un-healthy response in itself on my part I know).  I feel that if one truly reads and heeds the fine print of a "Considerable" rating, it is a good indicator of the complex dangers, mysteries & uncertainty of BC travel.  Key words/concepts including:
-Dangerous Avalanche Conditions (the first descriptor-obvious?)
-Natural avalanches possible, human triggered likely (how many other 'go for it' decisions made in life be they recreationally, financially, emotionally would we make if violent outcomes were "possible to likely"?)
-'Avalanche Size & Distribution' column lays out a wide variety of sizes as a possibility, which to me reads not as "If" but "When".

I'm curious if folks think it's not enough of a warning for the un-trained & in-experienced mountain travel sort (who don't read the fine print of the rating), or falls short even for people of "experience" going into the backcountry?  Am I being small-minded here and missing an important point?

Submitted with honest inquiry and openness towards other ideas.

By having an odd number of ratings, the middle one becomes the default grey area that tints other elements of the decision process.

My problem with the "considerable" rating is not that people go out with fine print as you've detailed, it's that the rating is broadcast just about anytime there is new snow. I've been out on plenty of days when the rating for the aspect that I'm on is "considerable" and I have felt very safe and have seen no signs of instability that would cause me to turn around. I have also been out on days when the rating was moderate and have turned around or chosen less adventurous routes.

I feel like "considerable" is the go-to rating when there is too much variation across a region or the forecasters want to error on the side of caution. I would appreciate a gray colored rating of "questionable" that is the equivalent of "considerable" in terms of potential for slides but without the assertion that they will happen.

Don't forget that the guys who were killed in Colorado were experienced backcountry travellers as were the Tunnel Creek victims, the Phantom Slide victims, the recent Utah victim, and many many more.

Personally, I'm having a very hard time accepting the notion that "Considerable" was/is not enough of a warning--almost to the point of feeling negatively judgmental towards a person who thinks that, and their ability to correctly make self-assessments and decisions in the BC....

I might be one of those... I don't think its a good idea to make a conclusion based on the rating alone. I put most weight on observations in the field/on the tour than I do the rating, and have turned around or altered my path on days rated moderate. For me the rating mostly influences the objective before I hit the trail, but the same mindset on the trail is applied regardless of rating. The rating is a regional thing.

My thoughts on the tragedies are related to large group dynamics. If we want to put a value on a rating then I think they ought to add a rating system based on group size, the same scale based on group size with 5 or more in the extreme.

I might be one of those... I don't think its a good idea to make a conclusion based on the rating alone. I put most weight on observations in the field/on the tour than I do the rating, and have turned around or altered my path on days rated moderate. For me the rating mostly influences the objective before I hit the trail, but the same mindset on the trail is applied regardless of rating. The rating is a regional thing.

My thoughts on the tragedies are related to large group dynamics. If we want to put a value on a rating then I think they ought to add a rating system based on group size, the same scale based on group size with 5 or more in the extreme.

Apparently the beginning of a decision process?

Apparently the beginning of a decision process?

correct

I feel like "considerable" is the go-to rating when there is too much variation across a region or the forecasters want to error on the side of caution.

maybe, its certainly used most. But I would rather the forecasters err on the conservative side the learning curve of its accuracy is more forgiving.

maybe, its certainly used most. But I would rather the forecasters err on the conservative side the learning curve of its accuracy is more forgiving.

I generally agree with erring on the side of caution but in this case I'm concerned about an issue of complacency if users of the system consistently see less activety than a forecast that includes "natural avalanches possible, skier triggered avalanches likely" would suggest.

My experience is 95% PNW snowpack so my observations and comfort level with snow is obviously biased.

I agree with your sentiment about complacency and seeing less instability than a ‘considerable’ rating implies but I think this breaks down to not being able to provide pinpoint avalanche forecasts within a region. This winter I skied an exposed line this on a considerable day, it was solid. The next day NWAC reported avalanches at a location adjacent to the ski resort ~3 miles away from ours on the same day we skied… it was certainly “considerable” over there one could argue the rating should have been high!

I don’t think there is going to be an easy solution. Put yourself in the forecasters shoes, if you had to post a rating for a region that all level of people are basing decisions on… I would not want that responsibility on my shoulders. The details are always in the report that might be more specific to the aspect we want to ski…. It’s up to the individual to remain diligent and not become complacent, identify all the risks and mitigate them to a level that they are comfortable with… and pray you didn’t miss something.

On a lighter note when once I was getting scolded by my friend for me not checking the forecast we got a good laugh when I jokingly replied what’s the big deal, how is that going to change our plans when it’s always considerable anyways?

On a lighter note when once I was getting scolded by my friend for me not checking the forecast we got a good laugh when I jokingly replied what’s the big deal, how is that going to change our plans when it’s always considerable anyways?

Haha, I can be accused of saying the exact same thing.

I don't envy the job of the forecasters and I can't thank them enough for the work that they do. I appreciate the details that are provided and that's where the best information is. I do get frustrated by backing down from things when the risk is above my threshold and watching other people put down good tracks. It's better to be safe than sorry though.

I am always torn as to whether or not I should even view the forecast.  The pseudo intellectual in me is biased to believe that more information is always better, but the dirtbag in me says, "screw the man and his fancy equipment."  Put another way, am I better off going into the field assuming the danger is Considerable to High and  then using observation and testing to determine otherwise or am I better off viewing the forecast and allowing it to color my decision making before I even put a ski on the snow?

It would appear to me that some interpret "High" as a reactive snowpack, and "Considerable" as a snowpack in which experts can usually play with a mitigable risk of consequence.

That's not what the terms actually mean .

"Considerable" states that human-triggered slides are likely, and that avalanche size can span the gamut of many small slides to rare but large slides. There's lots of room in there for a reactive snowpack.

To me, the biggest distinction between Considerable and High is the likelihood of natural slides. I often think about the "high side of Considerable" and the "low side of Considerable", as well as a "high side of Moderate".  I didn't get to play in the snow two weekends ago, but my impression is that NWAC got it reasonably right. There weren't widespread reports of consequential natural slides, but human triggered slides were widely reported.

It's easy to be lulled into Considerable complacency by the days when the hazard is obviously more than Moderate, but easily mitigated, and be lured into danger when the hazard is less than High, but demands full attention to safe travel. Don't rely on a hazard rating alone to encapsulate danger -- there's a lot more in the discussion, telemetry, and the weather forecast. The whole point of an avalanche education is to make local decisions for ourselves. Forecasters can't do that, and shouldn't bear that burden.

A five-point danger scale is good; humans understand five-point scales (look at climbing, whitewater, etc.). Distinctions of finer gradation are hard to comprehend, though people will argue to no end about the meaning of "third class". I sometimes wish that the forecasters would give Moderate slightly more teeth; for many backcountry travelers, there's little distinction between Moderate and Low -- it's the difference between "Go!" and "Bomber!".  As Scott Schell and others have said, the scale is kind of logarithmic; each step up the ladder is a multiplication of the hazard, not an increment.

Charlie, I am advocating for the elimination of the "Considerable" rating and working with just four ratings.

I fail to see where having the considerable rating provides useful input for the large number of users that become jaded to the rating, and that it provides little usefulness in post-event statistical collection as so many avis involving skiers occur during the considerable rating.

How would redefining the rating system change the way people make decision’s? The majority of accidents are always going to happen in the middle of the scale however it is structured… I would be concerned this setup would only shift the complacency if at all. I think the effects of complacency and large group dynamics should be a focus of discussion and education, I suspect those topics are the correlation in recent tragedies.

Kindly let me know if the following should be another thread.

From some comments above, it sounds like groups of 3-4 is the optimum for BC skiing safety in avalanche terrain.

Personally, I prefer groups of 5-6.  Small enough to maintain discipline when desired or needed (e.g., one-at-a-time and keep the person behind you - your rescuer! - in sight) plus plenty of diggers if anyone is completely buried.

What is the rationale for other group sizes?  Anyone have actual data regarding the affect of group size on recovery outcomes?

Thx
Mike

There's nothing wrong with the word "considerable" and the Considerable rating. It's defined in reasonably clear terms if you take the time to find the definitions as Charlie posted. All aspects of an avalanche forecast including its shorthand terms conceivably are subject to misinterpretation. Which can only really be mitigated if the reader has enough BC experience or training to know what forecasts mean practically.

What bugs me far more is the second guessing about the particular scale term used on the report on the day of some incident ("NWAC said the rating was only 'Considerable'. How could that happen?"). Too often this gets picked up or is started by people that don't really know that much about the role of avalanche forecasts in the bigger picture. Can be ONE decision point in the entirely personal process of staying alive in avalanche terrain but it's just one component of data that could be used, sometimes the least relevant one by the time you are actually on the hill.

What's more interesting to me anyways about using forecasts and scale isn't the "Likelihood" column in the definitions , it's the "Travel Advice" column. Considerable is "take time to consider whether the terrain you're on could be avalance terrain, even if it's not immediately obviously so", and High is "if there is ANY question in your mind of whether you're on avalanche terrain on this particular day ... you probably are."

It's been a while since I've posted, but this is a topic that interests me and I'm going to troll and then leave.

Now back to the topic. I think that the considerable rating is needed and is correct in its definition (without picking it apart). I think that the biggest trap has nothing to do with what the rating says, or is based on. The problem I think people have is: "Considerable" = "great fucking turns". As in, it has snowed enough that its deep and fresh, and human triggered slides are likely and naturals are possible.

A second observation in general is that spring warming is incredibly dangerous, though results vary to a high degree. As in, during the winter when its cold cohesive slabs are less widespread due to cold temps, but during the spring a bit of warming can easily turn a new dump from uncohesive and fun, to cohesive and dangerous quickly. So the line between "possible and likely" is more complex.

A bit about me. I ski in the Tahoe basin mostly, and I ski alone probably 50% of the time. I am scared of open terrain, but love skiing trees and chutes because I feel more comfortable making decisions there, even when its steep. For the sake of my background and experience I'll make the following gross generalization: avalanche conditions in Tahoe area can be dumbed down to danger increases towards the Sierra crest due to wind loading. So it's easy to have natural avalanches possible at the crest, and human triggered avalanches unlikely a 1/4 to 1/2 mile east. Somewhere in the moderate to considerable range most the time its snowed recently.

On another tangent, Craig Dostie has some words on variability and avalanche ratings from April 3 on earnyourturns.

Kindly let me know if the following should be another thread.

From some comments above, it sounds like groups of 3-4 is the optimum for BC skiing safety in avalanche terrain.

Personally, I prefer groups of 5-6.  Small enough to maintain discipline when desired or needed (e.g., one-at-a-time and keep the person behind you - your rescuer! - in sight) plus plenty of diggers if anyone is completely buried.

What is the rationale for other group sizes?  Anyone have actual data regarding the affect of group size on recovery outcomes?

Thx
Mike

Though not about recovery outcomes, there is some interesting data on the amount of risk that groups of difference sizes expose themselves to in "Heuristic Traps in Recreational Avalanche Accidents: Evidence and Implications" by Ian McCammon ( avalancheinfo.net/Newsletters%20and%20Ar...s/McCammonHTraps.pdf ).

"A number of investigators have suggested that party size may have played a role in decisions leading up to avalanche accidents. A “risky shift,” or the tendency of larger groups to take more risk, has been discussed frequently in the literature... there is a significant variation in exposure score by party size. It appears that people traveling alone and people traveling in parties of six to ten exposed themselves to significantly more hazard than people traveling in parties of four and more than ten people."  (check out the PDF to see the figure of the data)

Also later in the article: "...leaders appeared to make significantly riskier decisions as the group size increased."

What is the rationale for other group sizes?  Anyone have actual data regarding the affect of group size on recovery outcomes?

The group size has nothing to do with who lives or dies when caught in an avalanche, the focus should always be on stability and risk mitigation. Larger groups only have the possibility to hinder recovery outcomes.

personally I prefer groups 3 or less.
most all of my tours are with only 1 friend, occasionally two, rarely 3 or more, we get more skiing done and communicate safety and risk mitigation more efficiently. Admittingly that logic started with me wanting to get more skiing in on the tour without regard to avalanches. But what I found over time was the conversations on the tour became more in depth about snowpack and stability etc. and I learned a lot more about the snowpack than with any past larger groups. Occasionally I still go on yurt trips that always involve a large group and the stability assessment is much more complicated. I've seen groups split up over stability disagreements or sometimes everyone stares at the most experienced for the decision...

Kindly let me know if the following should be another thread.

it is off topic but its a good question.

The group size has nothing to do with who lives or dies when caught in an avalanche, the focus should always be on stability and risk mitigation. Larger groups only have the possibility to hinder recovery outcomes.

personally I prefer groups 3 or less.
most all of my tours are with only 1 friend, occasionally two, rarely 3 or more, we get more skiing done and communicate safety and risk mitigation more efficiently. Admittingly that logic started with me wanting to get more skiing in on the tour without regard to avalanches. But what I found over time was the conversations on the tour became more in depth about snowpack and stability etc. and I learned a lot more about the snowpack than with any past larger groups. Occasionally I still go on yurt trips that always involve a large group and the stability assessment is much more complicated. I've seen groups split up over stability disagreements or sometimes everyone stares at the most experienced for the decision...


it is off topic but its a good question.

Great reply.

Your mind has to be thinking through the entire journey.  Think of the landscape as constantly changing location to location and moment to moment.  Listen to your spider sense!

A bit about the history of the "Considerable" rating: It was added a number of years ago because it was thought that there was too much spread between "Moderate" and "High". At the time the terms "Considerable" and "Moderate to High" were put forward. I favored the term "Considerable" both because it was different and also because of the definition of the word "considerable". "Moderate" hazard is more cut and dried, certainly with a good base of knowledge and experience and conscientious decision making, "Moderate" hazard can be managed with leeway for PWKL's. "High" hazard should mean to experienced backcountry users that only safe terrain is reasonable. "Considerable" is different from "High" in that there are likely to be fewer naturals and the avalanche hazard is likely to vary more by aspect as well as being somewhat lower overall.

Regarding "Considerable" hazard, I believe a good number of people treat it as they should "Moderate" hazard, likely because their experiences have shown that they can ski terrain without getting caught, but that is something of a trap because most forecasters would tell you that in "Considerable" hazard they would expect to hear of a few incidents. Thus the fact that one doesn't get caught in "Considerable" hazard is really just playing the probability game. Sooner or later you get caught. For me, in "Considerable" hazard the amount of snow that might slide and the nature of the terrain regarding consequences are the determining factors.

Has there been any decrease of avi incidents or deaths since the inception of the "considerable" rating if adjusted for increased BC skiers and sledders?

Has there been any decrease of avi incidents or deaths since the inception of the "considerable" rating if adjusted for increased BC skiers and sledders?

Whether there has or hasn't been a per-capita shift in accident rate, it would be hard to prove that a change in rating system had any causative effect. The advent of Considerable
also correlates well with fat skis, a backcountry culture that condones risk, superior avalanche rescue equipment, smartphones, and the Red Sox winning the Series.

It's hard to see how backcountry travelers might travel more safely with less-detailed primary information from forecasters.

Whether there has or hasn't been a per-capita shift in accident rate, it would be hard to prove that a change in rating system had any causative effect. The advent of Considerable
also correlates well with fat skis, a backcountry culture that condones risk, superior avalanche rescue equipment, smartphones, and the Red Sox winning the Series.

It's hard to see how backcountry travelers might travel more safely with less-detailed primary information from forecasters.

So would bc travelers travel more safely with more-detailed primary information from the forecasters? Or is the current system that essentially equates "best skiing-but be careful" with "considerable", adequate considering the incidents, especially those involving supposedly knowledgeable types?

If no information was available would that change skier behavior or real-time analysis? My hunch is that once someone latches on to a specific rating, that rating shades most further analyses, and that a basic go/no-go decision has already been made. Perhaps the ratings are best for directing skiers towards trailheads, but decisions beyond the car seat be done with eyes-wide-open and the assumption that all snow conditions are entirely local and not reflected by a general forecast.

I keep asking the question because folks like you seem to think it works and I am still waiting for a convincing answer. I clearly understand the culture of risk and the advances in gear and rescue gear as it plays out in the world of ski touring.

As for the Sox... well I grew up in Baltymoor, Sox suck!

My problem with the "considerable" rating is not that people go out with fine print ...

Don't forget that the guys who were killed in Colorado were experienced backcountry travellers as were the Tunnel Creek victims, the Phantom Slide victims, the recent Utah victim, and many many more.

Lou Dawson Dawson's report has spent a lot of time analyzing the Colorado tragedy; it is apparent that the group was unable to either accurately process the most recent avalanche statement or evaluate the terrain they decided to cross.

The major problem in most avy incidents and the major challenge to most bc travellers is in cognition--how to gain, process, and apply information in decision making.  Most of us fail at one time or the other.  We are most likely to fail in fulfilling our personal responsibilities in a group (diffusion of responsibility; submission to the most outspoken, forcefully spoken, etc. person or persons).

I think the "Considerable" rating is an especially good one: it says "think about it! before you leap/traverse/climb; thinking means gathering all available signs, symptoms, experience and applying them in an effective way.

Lou initially began by questioning avy info and training/education processes (the group was in a course) but then became astounded by the failure to recognize plainly written and patently obvious information.  Not that the group was ignorant, or even unaware, of the potential for danger; many had avalungs or airbags (none were deployed); I believe all had shovels, beacons.  Apparently they just didn't think straight (think critically and insist on group critical thinking [full participation by all] in decision making).

So the implications of a "considerable" rating will be lost to those refractory to the information it contains; no other words will prove to be more effective.

I think the "Considerable" rating is an especially good one: it says "think about it! before you leap/traverse/climb; thinking means gathering all available signs, symptoms, experience and applying them in an effective way.

...

So the implications of a "considerable" rating will be lost to those refractory to the information it contains; no other words will prove to be more effective.

I think these are two great points and agree with the use of "Considerable" if it came with a warning to "consider your plan for the day including familiarity with the snowpack, weather history, and terrain" before making decisions on whether travel on a specific slope is feasible. This would put more pressure on the backcountry user to make their own decisions because the avalanche forecast does not cover an entire region with enough detail to make specific decisions about specific slopes.

Obviously, when the danger is "high" most backcountry users should avoid any threatening terrain and when it is "low" it is generallly safe for novices with a minimum of avalanche awareness education.

My other big issue with the "considerable" rating is the opposite of the complacency concern that I already expressed, it's that the media grabs it and sensationalizes the dangers. I know it's what the media does but to say that it's foolish and asking for death by skiing anything out of bounds on any day that is "considerable" paints us all in a bad light. Maybe I'm alone in the idea that i always feel like I can find somewhere relatively safe to go on "considerable" days but since I usually find other fresh skin tracks on my days out and about I doubt it.

So the implications of a "considerable" rating will be lost to those refractory to the information it contains; no other words will prove to be more effective.

Just reading through the comments quickly i think the word that best sums up many of the comments is human factors.

In Bruce Trempers book he has a whole chapter (chapter 10) on what he calls human factors. He lists the primary factor in fatal avalanches from 1990-2000 as "Human" and overconfidence as being the primary reason.

My favorite table of the whole book however is under the title "Common Mental Shortcuts" of which he lists; familiarity, acceptance, commitment, expert halo, scarcity, and social proof. Social proof is my favorite one and refers to the herding instinct that we all observe in the sidecountry or heavily traveled areas. Social proof seems to be a very dire problem in the revelstoke sidecountry where you can see large aggressive lines from inbounds that are only a 20min bootback away which leads right back into the resort.

My point is that as many have already pointed out the main problem with the considerable rating is not that it isn't clear on the risks the considerable rating implies, it is that it is the rating at which human factors are the most likely to occur. In the interior I believe this is a larger problem then for you guys on the coast as the rating is considerable 3/4 of the time or more midwinter.

While human factors can lead people to be overconfident with the information they gleam from the avalanche bulletins. I do not believe this is reason enough to reduce the amount of information available on current conditions. In fact I would like to see the amount of information released increased.

Sorry for any errors or redundancies in my post but I have to get ready for a weekend of skiing now and do not have time to check everything over. Just throwing in my 2 cents.

Personally, I'm having a very hard time accepting the notion that "Considerable" was/is not enough of a warning--almost to the point of feeling negatively judgmental towards a person who thinks that, and their ability to correctly make self-assessments and decisions in the BC (an un-healthy response in itself on my part I know).  I feel that if one truly reads and heeds the fine print of a "Considerable" rating, it is a good indicator of the complex dangers, mysteries & uncertainty of BC travel.  Key words/concepts including:
-Dangerous Avalanche Conditions (the first descriptor-obvious?)
-Natural avalanches possible, human triggered likely (how many other 'go for it' decisions made in life be they recreationally, financially, emotionally would we make if violent outcomes were "possible to likely"?)
-'Avalanche Size & Distribution' column lays out a wide variety of sizes as a possibility, which to me reads not as "If" but "When".

I'm curious if folks think it's not enough of a warning for the un-trained & in-experienced mountain travel sort (who don't read the fine print of the rating), or falls short even for people of "experience" going into the backcountry?  Am I being small-minded here and missing an important point?

Submitted with honest inquiry and openness towards other ideas.

Remember that we are talking about an internet-based rating system, not an observation based rating system for those considering backcountry travel.  The reader has little else to go on than what is in the report.

I find the "considerable" rating to be the absolute most useless rating in the entire system, and am surprised by the number of enthusiasts that are jumping to its defense.  Red and Black being Extreme and High are simple.  They tell me to do something else.  Buy a lift ticket, pull weeds, take the kids to the zoo, whatever.  Green is also easy - you never ever see it so it may as well not exist.  Yellow then serves a role that may as well be green for all practical purposes, and I believe many people interpret this to mean "yellow means go".  Orange or "considerable" represents a lot of the time that I would bet most users of this website are out in the backcountry.  If you stayed home when it was "considerable", you would be staying home a lot.  In my opinion, "considerable" means "you are on your own" and that the forecasters can't make broad observations or predictions. 

A traffic light type of analysis is basically useful for people to make stay or go type decisions from the comfort of their keyboard.  All the colors of the analysis lend themselves fairly well to that type of decision, but orange does not.  Orange won't tell you whether to stay or go, but tells you to figure it out on your own by going and evaluating conditions the old fashioned way.  Orange requires more thought than any of the others.

We shouldn't be surprised that an attempt to oversimplify avy study into a traffic light signal provides an unsatisfactory result.

Discussions like this can be useful in that they may prompt the inexperienced to better learn the system we've got.

"Considerable" is as clear as it's English definition.  Efforts to educate others on what it means regarding avi forecasting would arguably be more productive than changing a system to make it less confusing for those unwilling to take even the most basic steps towards educating themselves on what is necessarily a fairly complex subject.  The current forecasting system is already really, really simple. I doubt the target audience would care if the "Considerable" was eliminated or changed - peer interaction seems to be a much more likely path to more widespread awareness.

You've got to pay to play (safely).   

I think the idea that the Considerable designation is somehow defective or a contributing factor in recent accidents shows a lack of ability in the criers, not in the avy professionals.

It is true that Considerable is put on some of the most challenging and rewarding touring days. With lots of a new snow and weather it is harder to make good decisions in the bc, that is certainly true. To rename those days High or Moderate would be a disservice. We should not look to dumb down our avy reports. I'll bet that the criers' frustration with those Considerable designated days is not the forecast as much as their inability to make a good plan to get out into the fresh for themselves.

I look at the avy forecasts as our professionals' informed guesses, often covering a large swath of mountains, on what the average party may encounter. I take the forecast as just one data point in my planning, with the largest set come from my recent time on the snow collecting locally relevant data as I travel, perceive, discuss and interact with my immediate surroundings. It is just not safe to take the avy report and proceed as if it is fact. This is how people get in over their heads, by not using them.

I've been out in plenty of "High" days where the conditions were very stable. I've also found very active snow packs, that we made move heavily, on "Moderate" days. This seeming contradiction with the forecast was never a surprise because the facts are what you see and feel, not what you read.

Please don't change a thing, except maybe giving more to NWAC so they can keep doing what they do.

Chuck, some "criers" have loads of experience in a variety of snowpacks. I simply ask the question, "what is the effectiveness of a rating that constitutes a large portion of the ratings listed during days in areas where avi fatalities occur?"

My thought is that between the normalization of risk (chances taken without consequence that alter the risk perception) among many backcountry skiers and increasingly crowded and more socialized places to ski, "considerable" basically defaults to GO and make sure your buddies are nearby.

Why not give some thought to returning to the four rating system?

The current system with its use of "considerable" seems to not be an improvement from my read of accident reports.