Happened over Christmas 1977 when the firemen went on strike.
I remember it well - though I was on an overseas posting at the time. I also remember having a great deal of sympathy for the firemen - this was the year many in the Armed Forces got their 'Irish pay rise' i.e., the increase in salaries was wiped out by the increase in messing & accommodation. ISTR I ended up with an extra 50p a week.