It’s forecast to be about 45 degrees in Victoria today, which means that people are thinking about bushfires. And when people think about bushfires, they check out the CFA (Country Fire Authority) website. But is the information they’re finding there useful?
After Black Saturday, the government came up with a new fire danger rating system that was supposed to make it clearer how serious the fire danger was. Let’s have a look at what they came up with:
First here’s the scale itself (which is used on the CFA homepage, roadside signs etc):
Can you tell what each level means? I got a bit confused between “extreme” “severe” and “very high”, so here’s an explanation of how the scale works. Pretty complicated.
Since the scale is supposed to help people make decisions that could save their lives, it’s pretty important to get it right. So let’s do a bit of a usability analysis to see if it’s working, and if not, think of ways to improve it.
Here are some of the issues I can see:
- There are two names for the top threat level
Two names ("Code red" and "Catastrophic") to describe the same thing is always going to be confusing. Which one do you use in a given situation? Do they both mean the same thing?
Let's keep the naming simple and consistent. The other levels are all named with adjectives, so let’s go with “Catastrophic”.
- The bottom two levels have the exact same action...
... which is "Check your Bushfire Survival Plan". If the users behavior is supposed to be the same, then why have they separated it into two categories? Seems to be adding unnecessary complexity. Unnecessary complexity is bad!
Let’s just join those two categories into one, and give it a new name.
- The second lowest value on the scale is “high”.
It’s a bit hard to take a scale seriously when it starts at “high” (colour-coded blue). The scale’s purpose is make people feel an appropriate amount of alarm depending on the situation. Also, when you look at the description for what you’re supposed to do at this stage, it basically says “don’t worry about it”.
Let's rename the lower end of the scale so it sounds a bit less alarming.
- The top two items on the scale are both red.
This makes it difficult to distinguish between them.
Let's use a unique colour for each item on the scale.
- The top label is really hard to read
This is because it's using white text on red/black.
Let's make sure that the text is readable for all items.
- It’s not clear from looking at the scale how to act.
What is the viewer supposed to do at each level? What behavior are we trying to create?
The scale itself should contain all the information you need to read it (without having to go elsewhere to “decode” it)
- The scale doesn't work if you're colour blind.
About eight percent of males are colour blind, so this is a pretty big deal.
Let's switch to colours that will work for everyone.
So let’s put all of those improvements into a new fire danger scale. Since the behavior expected when the fire danger is “extreme”, “severe” or “very high” is basically the same, I’ve rolled them into one category. Same goes for “high” and “low-moderate” which also have the same behavioral expectations. Basically, we want people to check out the fire danger and do one of three things. Leave, stay and defend, or not worry about it.
I’ve given each category a new name, and integrated the description/behavior guidelines into the chart. It also takes up exactly the same amount of space as the previous chart. And when colour blind people look at a map with these colour codings, they’ll be able to make sense of it!
OK, it’s pretty ugly, and it’s far from perfect but at least it’s food for thought!
