Ask the Expert Q&A, 30 October: Environmental Matters by Mick Stanley
Mick Stanley, formerly Head of Hull City Museums and Galleries, will be answering your questions on Environmental Matters in Museums on Friday 30 October between 2-3pm BST.
Mick Stanley was formerly Head of Hull City Museums and Galleries, and Head of Earth science, RSNC. Mick is currently working as a museum and heritage consultant and Environmental Adviser to the Government’s Indemnity Scheme for the loan of objects and works of art to non-national museums.
A secure perimeter is a pre-requisite for any building that houses objects, specimens and works of art, and all buildings that contain collections must also have the correct environment for the continued existence of those collections.
However not all repositories of cultural collections adhere to the recently defined “Specification for managing environmental conditions for cultural collections” that are in PAS 198 : 2012. The publically accessible standards will cost you £60 to download, but the specs are worth the cost as four parameters, relative humidity, temperature, light and pollution are explained and detailed. All of these parameters should be monitored and recorded if your institution manages collections.
The Government Indemnity Scheme for the borrowing of material from non-national institutions allows public access to objects within the UK by providing borrowers with a free alternative to the cost of commercial insurance, which means that objects in the event of loss or damage, are covered by Government. There is a thorough security and environmental risk assessment of the venue, exhibition area and transport following an application which must reach Arts Council England, that manages the scheme, at least 3 months before the loan period commences. If your institution is not applying to GIS for loan material whether for exhibition or long term loan it should be!
Free insurance of course comes with a cost as GIS requires the minimum and maximum conditions for relative humidity to be between 40-65% with a maximum cycle of 10% within 24 hours, and temperature between 16°-24°C with a maximum cycle of 4°C within 24 hours. The rh and temperature must be continuously monitored and sampled at 30 minute intervals. There is also a requirement to keep the records as applications for loans necessitate the provision of earlier environmental graphs to prove that conditions are within the parameters of the scheme.
The Scheme also requires that light levels, measured in lux, and UV, measured in micro watts/lumen, i.e. the strength and duration of light, either natural or artificial, falling on objects and works of art, must to be controlled, monitored and recorded. These should be continuously sampled, but at a minimum the levels checked before each exhibition with a hand held meter, to be within the tolerances that follow. Objects moderately sensitive to light, e.g. oil and tempera painting, fresco, undyed leather, horn, bone, ivory, wood and lacquer must not exceed 200 lux or 600,000 lux-hours per annum; ideally much less by reducing the hours works are exposed to artificial light. Simply switching lights off when the space is not open to the public and closing blinds and shutters will reduce the exposure, and give closer control of the environment. Objects highly sensitive to light, e.g. textiles, costumes, watercolours, tapestries, prints and drawings, manuscripts, miniatures, paintings in distemper media, wallpaper, gouache, dyed leather and most natural history exhibits including botanical specimens, fur and feathers must not exceed 50 lux or 150,000 lux-hours per annum, ideally much less.
Mick Stanley
Mick Stanley, will be answering your questions on Environmental Matters in Museums on Friday 30 October between 2-3pm BST.
You can post questions before the Q & A session, on 30 October, or you can converse in real time with our expert. You can use the comment box below to post a question, or you can use twitter with the hashtag #mdyask.
Comments have to be moderated, to protect the blog from spam, so if your comment doesn’t appear straight away, don’t worry, we’ll get to it as quickly as we can.
If you have a problem submitting questions, either in the comment box, or via twitter, please email your questions to gillian.waters@ymt.org.uk
If you have ideas for subjects you’d like to see us cover in future, or would like to take questions yourself, please get in contact with us and let us know.
Your Comments
Gillian Waters |
Dear Mick
I was wondering if you could recommend the sort of equipment needed to monitor the strength and duration of light, either natural or artificial, falling on objects and works of art?
Gillian
Mick Stanley |
Dear Gillian,
There are a number of continuously recording sensors that are usually part of an suite of sensors that monitor and record lux and UV. Traditionally museums, galleries, houses etc have used a hand held light and UV meter for spot checks, but that is insufficient for GIS purposes, and I would suggest for proper collection management. The natural methods use blue wool cards that fade if the UV and lux are over the limit. These cards are used by the National Trust.
Mick
Gillian Waters |
Thanks Mick. I was wondering why spot checks on light levels cannot be used.
Gillian Waters |
bridgetmck asks What is the public responsibility of museums to tackle global environmental challenges? How do you see the ethics?
Mick Stanley |
Gillian, Spot checks can be used however recording light and ultraviolet radiation is an important part of environmental management, and the monitoring and recording will help to protect collections, reduce the need for remedial conservation, train staff and volunteers in an essential museum skill, and support future GIS applications.
The regularity and frequency of monitoring depends on the light-sensitivity of the GIS loan items, the exhibition programme and what lighting is in the building. A basic rule of thumb is to monitor and record light levels before every new exhibition and, if there is natural lighting in the museum, this should be continuously monitored to ensure that exposure can be limited and that UV is reduced down to 10 microwatts per lumen (μW/Lm) or removed completely.
If you are taking spot readings in order to build up a picture of the changing light in a space over time and season it is vital that you always take readings from the same positions.
Your recording system for light and UV will depend on how you take the readings and the purpose of the monitoring. Sometimes it is easier to mark light readings on a plan of the space, sometimes it makes sense to record daily changes on a table. Whichever recording system you use you should always include notes or relevant information to help anyone reading the record to understand what they are seeing. This will include noting the date and time of the reading, and might also include information such as the weather, whether windows were covered or not, and any changes to the lighting scheme that might have been made.
The GIS scheme requires monitoring and recording of lux and UV for the duration of a loan, and for the same period of time of the loan from one year previous. It therefore makes sense to record continuously.
Mick
Mick Stanley |
Gillian, More comments on the equipment to monitor and record lux and UV.
In museums, light is measured in terms of its concentration and expressed in Lux, which is one light unit (Lumen) per square metre. Ultraviolet radiation can be measured as an absolute, in microwatts, or expressed as a proportion of the light. In museums, it is normal to use the proportional measurement, which is expressed in microwatts per Lumen (μW/Lm). There is a range of light and UV monitoring equipment available and prices vary too, depending on accuracy and sophistication.
Using spot readings is still the most common way to monitor light in museums, but there are instruments that log total light exposure over time and increasingly museums are turning to dosimeters to monitor the effects of light. This is because the effects of light are cumulative and it is more important to consider the total light exposure that an object may be receiving, than to know the light level at any one time.
Light meter
The light meter contains a photosensitive cell which is able to match the way the human eye perceives light. The photocell converts light energy to electrical energy which in turn is read off a scale or represented digitally.
Ultraviolet meter
This meter works in the same way as a light meter, again using a UV-sensitive cell to convert UV-radiation to electrical energy.
Combined Lux and UV meter
There are some instruments available that combine light and UV measurement in one instrument, but use the same technology as described above.
Dosimeters
This method of monitoring the effects of light has been around for a long time. Dosimeters work on the principle that light will cause a perceptible amount of fading of organic material (usually dyes) over time. The blue wool scale is the most well known dosimeter system; it was developed for testing the light-fastness of dyes. Blue wool dosimeters fade in light conditions to a known degree. This means that, by comparing a faded dosimeter with the scale, it is possible to find out how much light the adjacent object has been subjected to. A more recent development is the LightCheck™ dosimeter which has been specifically developed for museums and galleries (see http://www.lightcheck.co.uk/).
Data-loggers, telemetric sensors and hard-wired systems
These instruments use photo and UV-sensitive cells to measure the light and UV levels and repeat the readings so frequently that it is possible to build up a picture of the cumulative light and UV. The data is relayed to a computer for easy presentation and manipulation.
Mick
Gillian Waters |
That’s Great Mick thanks.
Mick Stanley |
Gillian, I wasn’t expecting questions on global environment challenges, but I am passionate that the public understand the effect that humans have on the Anthropocene, the epoch in which we live, and also the fact of global warming which is undoubtedly helped by our adding gases into the atmosphere. However it is through understanding past climates that we understand the present and we know that CO2 levels were higher in the geological past.
Museums have a responsibility and a duty to mirror society through their collections, and to inform the public through the interpretation of those collections, and their place in the wider scheme of things. The public responsibility is to present and inform on global environmental challenges through the collections were possible, and museums with natural science collections clearly can present and inform.
Mick
Mick
Mike Linstead |
@bridgetmck · to @Stanmick Thank you. I agree but probably go further as I see museum learning as dialogic, inspiring active citizenship #MDYask
Gillian Waters |
Andrew Woods @YMT_Coins · asks
#MDYask What would advice be for museums new to monitoring/working with #environmentalconditions?
Mick Stanley |
Dear Andrew,
Give me a ring and we can discuss with a little more time, Gillian has my number.
Mick
Mick Stanley |
Dear Bridget,
Every Museum service I worked in over 35 years had an education department, and not surprisingly I share the ideal to inspire active citizenship. As a three times Mayor of Ripon I know politically how hard it is to galvanise local citizens to be active and involved, and I have found that only if citizens are challenged financially or see injustice are they sufficiently goaded into action. Keep wanting the dialogue, and we may get there eventually.
Mick
Mick Stanley |
Dear Gillian,
Have enjoyed the online ask the expert, and thanks for your questions. I am prepared to have another session in the future, do let me know.
best wishes
Mick