Sir, – Here’s a simple mathematical tip for journalists to avoid arguments with street protesters about crowd numbers – each square metre of standing space can safely accommodate three people, depending on body size and fixed obstacles (parked cars, street furniture, etc). It’s possible, therefore, to fit 9,000 people into 3,000 sq m. As an example, Croke Park has standing space – about 3,500 sq m – for 8,800 spectators.
The area of the streets (including footpaths) on either side of Merrion Square can be accurately calculated – the length of the north/south side of the square is twice that of the east/west side, the latter being about 180m. The four sides together at, say, 20m wide (allowing for obstacles) produce standing space of about 21,600 sq m. Multiplying this parameter by three equals 64,800 people. Substituting the east side of the square for Mount Street, and Merrion Street, Lower Clare Street and Nassau Street, it’s very probable that more than 70,000 people could have attended last Wednesday’s water charges protest.
That’s engineering for you! – Yours, etc,
JOHN GREANEY,
Killiney, Co Dublin.