[14 SEPTEMBER 2021 UPDATE]:

A few weeks ago a member of Dublin Fire Brigade explained "blocking" in an online post. It was something that I have noticed but I thought that it was random, but as a result of the post, I decided to examine some old photographs from Dublin, Belfast, Cork and Limerick. These images from Limerick stuck in my mind because it was the first time that I actually noticed the way the fire engines were arrange. Also I was on my way to the Jasmine Palace restaurant and was near the accident when it happened but it is not my policy to photograph road accidents I only photographed the emergency services in action because of their traffic control technique.

A block is when an emergency vehicle such as a fire engine is used to protect an incident work area by parking across a lane or lanes of traffic. The unit should be stopped upstream of the incident area and parked at an angle across a lane or two of the roadway or street. In many cases, the shoulder of the road will be considered a lane if that is where the original incident is located.

Parking at an angle makes it easier for approaching traffic to identify that the unit is stopped, parked and not moving. Units parked in line with traffic, even on the shoulder, are not as easy to identify as stopped and approaching traffic will often not recognise that the unit is parked instead of moving with traffic.