I almost decided to stay at home today and call in sick.

I'd spent half the night fretting and wondering how my family would cope without me, should I perish on my way to or from the office.

It was my own fault - I should have known better than to carry out a risk assessment on my journey to work.

I'd made a mental note of all the possible traumas that could befall me - someone crashing into my car, my car crashing into someone else's car, an animal darting out into the road, a patch of oil causing my car to skid, my brakes failing... the list was endless.

Assessing risk is like looking up an ailment on the internet - there are so many terrible scenarios that it would be better not to know.

But risk assessment is a big business. On my way to work I pass a firm of risk assessors and often ponder what its workers do. I imagine them being presented with hare-brained plans by people like Bear Grylls, asking for advice on whether it is okay to windsurf across Afghanistan or paraglide over the Grand Canyon.

Last week, however, I got a little more insight into what goes on when I accompanied my youngest daughter on a school trip to London.

It was a brave thing to do, take dozens of primary school-age children to the capital, herd them onto packed tube trains, take them to an exhibition, on a river trip, a tour of the Houses of Parliament, and a walk around the major attractions.

And it was clear from the start that hours of meticulous planning had gone into organising the day, and that a key part of it was risk assessment.

Included in my helpers' pack' was a form listing every possible problem that might arise, and what to do in each case - from a child going missing or being injured, to an adult being injured.

I don't think risk assessment came into play on school trips when I was young. From what I remember, we were taken to a destination and let loose, resulting in scenarios like those in Willy Russell's superb play Our Day Out.

There was always trouble, with children going where they shouldn't, getting into scrapes, and we invariably spent ages waiting for stragglers who were late for the bus home.

Much more care and attention is devoted to outings nowadays. But if you dwell on it, risk assessment could make you paranoid. Nothing we do is without risk, even simple everyday tasks like getting out of bed - in fact, the night before the trip, my daughter's head teacher badly injured his toe on a piece of bedroom furniture.

Eating a meal puts you at risk of choking or food poisoning, there are all manner of risks associated with gardening, and I remember a case of a woman who died after hitting her head when bending to drink from the tap after cleaning her teeth.

Thankfully, the London trip went smoothly and a fantastic time was had by all. Whether it will spur the school on to even more ambitious outings, I don't know. Beijing for the Olympics, perhaps?