Video Transcript
Which of the points of the graph of risk
and hazard severity best corresponds to the activity of measuring the temperature of water
being boiled in a beaker that is heated over a Bunsen burner?
Okay, so in this question, we’ve been
told that we’ve got a beaker of water. And this beaker is heated with a Bunsen
burner until the water is boiling. Now, we’re trying to measure the
temperature of this water. So we need to stick a thermometer in the
water as well. Now, let’s start by identifying the
hazards in the setup.
Well, first of all, we’ve got boiling
water which could be spilled and that is a hazard. And secondly, we’ve got a Bunsen burner
which is switched on; that’s also a hazard. So these are the two hazards in our
setup. Now of course, there are more. But these two are the main ones.
So let’s now think about the hazard’s
severity. In other words, if things were to go
horribly wrong, how bad would it be? Well, if somebody was to first of all put
their hand close to the Bunsen burner, then they would get potentially burned by it and that
is actually really severe. And as well as this, because we’re
dealing with boiling water, that could potentially be spilled resulting in scalds and yet
more burning. So for the hazard severity, we can say
that due to the possibility of scalding and burning, the severity is high.
And finally, let’s think about the
risk. Now, risk is to do with the estimated
probability of something going wrong: how likely is it that something bad will happen? Well in this situation, if we’ve got a
beaker of water that’s boiling on a Bunsen burner, assuming that everything else has been
set up correctly, such as the tripod on which the beaker is balancing, then the only thing
that the experiment has to do in order to measure the temperature is to put the thermometer
into the beaker of water.
Now they can do this when the water is
boiling which is slightly dangerous or they could have done this before the water was even
boiling, even before the Bunsen burner was switched on. Therefore, it’s likely that the order in
which the scientist set up this experiment is that they fill the beaker with water, put the
thermometer into the beaker, set up the tripod and the beaker on top of it, and only then
switch on the Bunsen burner. Once all of that is done, the only thing
that the scientist has to do is to read the temperature on the thermometer.
This means that they don’t have to touch
the setup whilst the water is boiling. And hence, the likelihood of anything
getting knocked over or them touching the Bunsen burner is really low. They’re basically not exposing themselves
to the hazard: neither the boiling water, nor the Bunsen burner. The only thing they’re doing is looking
at the thermometer from far away. And hence, the risk can be said to be low
because of the low exposure to the hazards.
So let’s now look at this graph that
we’ve been given at the question. On the vertical axis, we’ve got
increasing hazard severity as we go up. And on the horizontal axis, we’ve got
increasing risk as we go across. So for this science experiment, we’ve
said that the severity is high and the risk is low. That means that we’re looking for a point
that is high up on the hazard severity axis, but low down on the risk axis.
We can draw dotted lines across and up
from both of these points on the two axes and see that the point at the intersection of
these two dotted lines is point 𝐴. In other words, point 𝐴 is the one which
shows high hazard severity, but low risk. And so, our answer to this question is
that point 𝐴 corresponds to the activity of measuring the temperature of water being boiled
in a beaker that is heated over a Bunsen burner.
