Wednesday 28 September 2022

Festival of Plastics

Earlier in September we attended the Festival of Plastics, held at the Museum of London.  This festival was a celebration of the COMPLEX project which was coming to an end after five years.  The project, run by UCL’s Institute for Sustainable Heritage, received funding from the European Research Council under the European Union’s Horizon 2020 programme (No 716390).  Our Chief Curator, Susan Lambert, has been a member of the project's steering group and we have been fascinated by the activity of the project from the beginning.

The festival included fascinating talks from a variety of speakers including a keynote from Yvonne Shashoua on the ‘Long term storage of plastics’ which was really interesting.  Yvonne wrote the seminal book ‘Conservation of Plastics’, a book we refer to regularly, so it was great to hear her talking on the subject again.

Yvonne Shashoua talking about the ‘Long term storage of plastics’. 
Image credit: Louise Dennis

We were not there just as observers.  Susan contributed a pre-recorded presentation about the project ‘A curator’s guide to synthetic garments’ which MoDiP has managed as part of the Plastics Subject Specialist Network (PSSN) alongside the Dress and Textiles Specialists (DATS).  The guide's purpose is to enable participants to improve the documentation and interpretation of collections of synthetic garments and to act as a stand-alone guide for basic synthetic textile identification.  It can be used alongside the other PSSN resources (A curator's guide to plastics and Confronting plastics preservation) to develop a fuller understanding of the various materials and their needs.

Susan Lambert's presentation about synthetic garments. 
Image credit: Louise Dennis

We also had a stall which offered us an opportunity to talk to delegates about MoDiP and the resources that we can offer to museums and other interested parties.  We took along objects from the Identifying Plastics Toolkit which caught the eye of the Institute of Conservation Modern Materials Network (ICON MMN) - thank you for the nice comments on Twitter guys, we aim to please.


A lovely tweet from ICON MMN.
Image credit: Fabiana Portoni

We found ourselves rather conveniently situated next to the UCL table, where there was an array of equipment on display and some amazing PhD students demonstrating how to identify different plastics materials using Fourier-transform infrared spectroscopy (FTIR).  Seizing the opportunity, we were able to analyse some of MoDiP's objects which we just happened to have bought with us (anyone would think this was pre-planned!).  We also bombarded the UCL team with questions as research for a project we are hoping to develop to test the rest of our collection.  Big thanks to Dr Katherine Curran, Louise Garner and Saya Miles for all of your help with this and apologies for monopolising so much of your time!

Katherine having a go at External Reflectance FTIR.
Image credit: Louise Dennis

Lastly, Louise also represented the museum during the panel discussion at the end of the day. She was flanked by Yvonne and Susan Mossman, Chair of the Plastics Historical Society, and joined by some of the other speakers from UCL and Tate.  This rounded off a great day full of interesting talks, networking and fact-finding opportunities.

Louise on stage for the panel discussion, second left.
Image credit: Katherine Pell.

Louise Dennis, Curator of MoDiP, and Katherine Pell, Collections Officer.

Wednesday 21 September 2022

Traffic lights, David Mellor, 1965

MoDiP recently visited the Yunex Traffic manufacturing facility in Poole to talk about traffic lights. The company supply, install and maintain traffic signal and control equipment for the BCP council, and had kindly offered to donate some plastics objects to the museum.

We were treated to a tour of the factory where we got to see examples of some of the 20,000 different variants of traffic light signal heads being produced for customers across Europe. The image below shows a green coloured signal head in polycarbonate, destined for Germany and looking very different to the styles we commonly see on UK roads.

A German signal head.
Image credit: Katherine Pell

We were then shown the repair centre where parts can be re-used from old stock. For example, if a junction has been updated and new signal heads installed, the old lights will be brought here. Anything that cannot be rotated ends up in the waste collection area to be recycled (refer image below).

The waste collection area.
Image credit: Katherine Pell

It was here that we were able to acquire a few new items for the collection, since our objects do not have to be in working order. Our host, Kelvin Shergold, had very kindly managed to secure us a David Mellor signal head from Somerset (Yunex Traffic maintain contracts with lots of different councils), which was the main reason behind our first contacting the company (refer image below).

Kelvin holding the Mellor signal head (left) and close-up detail (right).
Image credit: Katherine Pell

David Mellor was commissioned by the Ministry of Transport to standardise the design of traffic lights in the UK in 1965. Updating a system that had been relatively unchanged since the 1930s, the project was in response to a 1963 report that concluded existing traffic management to be out of date for both the increased numbers of vehicles on the road and their increased speed. The new signal head required improved visibility, had to be adaptable to include additional signage such as filter arrows where necessary, and needed to provide more assistance for pedestrians crossing the road.

Original drawings (left) and the new signals on trial in London (right).
Image credit:

The Mellor signal head was introduced in 1968, with the individual lights encased within a blow moulded unit in polypropylene (PP). Two flat panels in polyethylene (PE) were screwed on either side to make the overall body much larger, outlined in polyvinyl chloride (PVC) reflective tape, and easily replaceable with different panels that incorporated a variety of regulating signs. Each light had a hinged opening at the front to access the bulb (whereas previously the fitting would need to be unscrewed), and large protruding, flexible, impact resistant visors in PE covered the new lamps to prevent natural light reducing contrast. The new signals were maintenance-free, with all components made of plastics materials, including the coating on the steel mounting poles.

A Mellor signal head in-situ, on the main road in front of the University.
The only other Mellor head I have spotted locally is at Winton Banks.
Image credit: Katherine Pell

Several manufacturers were employed to produce this design throughout the 1960s-1990s (MoDiP’s example was made by Plessey Automation) before it was superseded. Yunex Traffic kindly donated a more modern traffic light signal head too (refer image below): a Siemens Helios modular design that contains all the internal componentry within one box that opens via two sliding clips at the front, thereby simplifying the process of installation and fault repair. The boxes are clipped together and holes in the mouldings provide passage routes for cabling.

The Siemens Helios modular design.
Image credit: Katherine Pell

We also came away with a puffin crossing unit complete with a tactile cone. This small piece of polypropylene (PP) extends out underneath the push button and is there to assist those with visual impairment and/or partial hearing to cross the road safely. When the light changes to green, the ridged cone rotates alerting the user. An amazing plastics design, it was invented by traffic engineer Richard Keith Duley in 1987 and was manufactured by Radix, a company he co-founded with Milan Fuchs the following year.

A tactile cone in-situ, beneath the Mellor signal head in Wallisdown Road.
Image credit: Katherine Pell

We would like to say a very big thank-you to Kelvin and Yunex Traffic for their generosity and also to my daughter Millie, who first told me about tactile cones. 

All of these objects are now available to view in the museum, on request.


Katherine Pell
Collections Officer



Wednesday 14 September 2022

Endurance: MoDiP’s new exhibition.

The enduring properties of plastics materials can have negative connotations, especially in relation to the pollution of land and oceans by poorly managed waste streams, single-use products, and those that are carelessly thrown away. Those same material characteristics can be put to good use to make objects that help people survive and thrive in stressful and difficult environments.

To endure a situation, whether by choice or circumstance, places specific demands on individuals and the equipment they choose to use. Objects made of plastics are used to provide water that is safe to drink when there is none readily available or ease the burden of carrying clean water long distances. By contrast, they can help prevent flood waters from entering our homes. Plastics are used in objects that are designed to support successful food production in arid climates, help to keep us safe from disease and offer protection from the elements in a crisis. They can be used to protect us from intense heat and flames, and conversely help us to sustain prolonged effort or activity in sub-zero temperatures and on snow.

Objects on display show how good design and the right choice of plastics materials can play a part in reducing risk to life and help us to survive in a variety of situations, including out at sea, in the air, and when travelling at high speed.

This exhibition will be on display until 10th March 2023 in the museum and is also available online.

Wednesday 7 September 2022

British Armed Forces NAAFI tokens

MoDiP has three different examples of plastics NAAFI tokens in the collection. With reference to the image below, on the left is a circular ½ d token, in the centre an octagonal ½ franc token and on the right, a circular green coloured token valid in NAAFI Egypt only.

MoDiP’s three NAAFI tokens.
Image credit: Katherine Pell

Established in 1920, the NAAFI (Navy, Army and Air Force Institutes) was an amalgamation of earlier organisations that had essentially been set up to feed the British Armed Forces. Administering all three services, by 1944 it was supporting military deployment through the provision of canteens, bars and shops, as well as controlling entertainment (ENSA) and leisure activities. Metal, paper and subsequently plastics tokens were all utilised, aiding the NAAFI by assisting with the organisation of supplies, controlling spending, preventing issues with local currency exchange, and avoiding the need to transport and deliver large amounts of heavy coinage.

AIBDC : 009324
Image credit: Katherine Pell

MoDiP’s first two tokens (refer images above and below) are made of the same material, although we are not exactly sure what that is! I have seen examples of these tokens variously described as: compressed paper, plastic, laminated plastic, wood, cardboard, bakelite, fibre and formica. Our guess is that it is a composite comprising a synthetic resin (possibly phenolic) bonded to either paper or fabric, hence the visible texture. The tokens are lightweight but strong and rigid, durable and water resistant. We are hoping to have them tested using FTIR (Fourier Transform Infrared Spectroscopy) soon, through which we hope to get a more definitive answer.

AIBDC : 009325
Image credit: Katherine Pell

We have dated the ½ d token to 1939-1945 but can be more specific for the ½ franc token based on information taken from ‘Over to You’, the official news sheet of the 5th Battalion Coldstream Guards (refer below). Edward Hallett, from his blog Tales from the Supply Depot, has published an excerpt dated 10th July 1944, that reports the introduction of the octagonal token as follows:

Excerpt from ‘Over to You’ news sheet, 10th July 1944.
Image credit:

A full transcript of the entire daily news sheet can be found here.

AIBDC : 009322
Image credit: Katherine Pell

With regard the NAAFI Egypt token (refer image above), I found the following contribution written by P.R. Bertram entitled NAAFI Numismatics, published in ‘The Quarterly Circular’ of the Egypt Study Circle (September Quarter 1993, Volume XV, No. 3).

Excerpt from ‘The Quarterly Circular’, September 1993.
Image credit:  

From this article we can state the manufacturer as British Artid Plastics Ltd with a date of circa 1951-1964. We believe this token was injection moulded in polystyrene (PS) but, again, FTIR will hopefully confirm this.
We also have many other types of plastics tokens in the museum, including a variety of Co-operative Society tokens (mainly for bread and milk), transport tokens and another favourite of mine, the British Restaurant tokens. All of these objects can be viewed in the museum on request.

Katherine Pell
Collections Officer