On one of our current projects we are being asked to remove sections of pugging in the floor void. For the un-initiated, pugging is a method of insulating between floors commonly used in the richer homes before the 19th century. It consists of plaster reinforced with horse hair, pressed onto timber laths under the floor timbers.
The less experienced in this field may decide to simply break up the material and remove it, but there is more to it than that. First of all, English Heritage don’t take kindly to the destruction of such a material, which would often give grounds for listing the structure. Secondly, removal of this material may give rise to the risk of anthrax. Yes, anthrax.
In 1895 controls were introduced in the UK which required animal hair being used for reinforcement to be sterilised by boiling prior to use. The purpose of this was to kill anthrax spores trapped in the hide, especially imported hides from China, Russia and Siberia. This new law greatly reduced the cases of anthrax experienced in certain factories of the time, and was quite a health boost in its day.
In 1919, The Lancet wrote of cases of anthrax caught by soldiers during the Great War from shaving brushes imported from the USA. Only 20 factories produced the brushes, and only a handful of these failed to sterilise the horse hair, which was generally imported from Argentina. A surprising number of deaths were attributed to this cause during the war.
There are no known cases of anthrax being caught from the removal of plaster reinforced with horse hair. It has, however, been confirmed that the anthrax bacilli can survive in a “dried” or dormant state for years, coming back into active life after being reintroduced to moist air. We follow the guidelines and our operatives wear masks and gloves when working. The area is also regularly vacuumed and cleaned.
When you work on heritage buildings, it does pay to know what you are doing. You only get one chance to get things right, and mistakes often cannot be reversed.
Tags: Anthrax, Archer-Hoblin, English Heritage, Graded buildings, heritage restoration, listed buildings