But I have just discovered something that may throw fresh light on the “accident” half of their title, specifically the accidents that are waiting to happen.

In 2017, according to a database of newspapers that I have consulted, the phrase “an accident waiting to happen” was used 247 times in the national press.

In 80 of those, the word “was” preceded “an accident waiting to happen”, in which cases I think we may safely assume that they comprised reports of accidents that had been waiting for an unspecified length of time but had now happened.

To analyse the accidents better, I drew up the following table of accidents waiting to happen and accidents that had been waiting to happen but had now done so for each of the last five years:

Year  Total Happened Waiting

2017   247    80            167

2016   335    78            257

2015   181    69            112

2014   232    83            149

2013   202    66            136

The column marked “Total” records the times “an accident waiting to happen” occurred; “Happened” are the times “was an accident waiting to happen” occurred; “Waiting” is the difference between columns 1 and 2, so gives the number of accidents still waiting to happen.

If we look at the ratios between the “Total” accidents and the “Happened” accidents, we see that an average of 31.4 per cent of accidents waiting to happen actually do so in any given year, so the expected waiting time for any given accident is about 100/31.4 years which is three years and two months.

But it is not as simple as that, for the table reveals one particularly interesting item: of the 335 accidents waiting to happen that were detected in 2016, only 78 happened, leaving 257 still waiting.

Yet in 2017, only 247 accidents were waiting to happen which raises the question of what happened to the other 10?

Clearly, for up to three years, we had been waiting for these accidents to happen, yet they had not done so and we had given up waiting. On the one hand, this could be viewed as a good thing: what had been an accident waiting to happen has not happened and is no longer waiting to happen. While we have been waiting, something has happened to make us no longer fear its accident potential.

The other possible explanation, however, is far more worrying: those 10 potential accidents have simply dropped off our radar.

They are still accidents waiting to happen but are not classified as such.

Perhaps we have grown tired of waiting; perhaps we have simply forgotten about them, though the danger is still there. There is a message here for us all, though I am unsure quite what it is. I suspect, however, that the figures conceal an accident waiting to happen.