Join us today for remote intern Mhairi Boyle’s second instalment of her four-part series on water quality and its impact on paper. Here she discusses the tests and analysis she undertook during her internship, explaining the chemistry and her results in an easy to digest way.

In this week’s blog, I will be discussing the water tests and analysis I have undertaken.

When doing this kind of research, it’s important to have real-life evidence to support your work. To start off, I created my own at-home experiments. This was my supervisor, Special Collections Conservator Emily Hick’s, great idea. My at-home experiments focused on the presence of chlorine and chloramine in tap water. To give you a bit of context, the chlorine content of tap water is something that concerns paper conservators. Chlorine is used to disinfect tap water to make it safe to drink, but it is also an oxidative bleach. This means that it has the potential to accelerate the degradation of paper-based objects, weakening them and making them more brittle, much like when you bleach your hair too much and it begins to snap off.

I wanted to firstly find out the chlorine content of my tap water, and also observe if the chlorine content varied drastically over the period of a month. I also wanted to compare the chlorine content to that of spring water, charcoal filtered water, and distilled water. I used WaterWorks test strips, which you dip into the water for ten seconds. The strip changes colour depending on how much chlorine is in the water. The results were quite positive. The chlorine level in the tap water and filtered water were very low, and varied slightly but not by much. The distilled and spring water had no chlorine, which made sense because they had both previously been purified.

Testing a water sample.

The Total Chlorine level of tap water from 26/04/21 – 21/05/21.

I also managed to analyse some on-site samples. During this most recent lockdown, most of the CRC has been closed to the public. However, a select few conservators have been allowed to go in on different days to complete essential work. Whilst on-site, the conservators have taken tap water samples for me which have been sent off for lab analysis by a company called IVARIO. Water was sampled from the CRC, St Cecilia’s Hall (SCH), and the University Collections Facility (UCF).

IVARIO’s Standard Test tests for almost everything that is of concern to paper conservators: metals, pH, conductivity, and more. As everyone knows, Scottish tap water is great, and so unsurprisingly the results came back very positive. All of the metals were under the maximum value recommended by Scottish Water; the pH was very close to neutral; and the water was deemed to be quite soft. There were slight variations, with the CRC and SCH samples differing from the University collections facility samples. This could be because the UCF falls under a different water supply area. Overall, the water at all sites performed very well.

A comparison of the on-site water samples to standards set by Scottish Water.

In my next blog, I will be looking into the opinions and practices of paper conservators from all around the world.