Hello.  In general, the lower the ambient temperature the lower the amount
of water in the air mass to achive a particular RH.  Sometimes the lowering
of the average ambient temperature or better still the mean tempareature,
enables marginal humidification/environmental systems to hold the desired
RH.

I prefer to try and hold the ambient collection storage temperature toward
the lower end of human comfort.  I expect that it is easier for collections
people to wear a thick lab coat and work in a cooler environment.

Of course, you have to be careful about "dew pointing". Having a humidistat
controlled heating system which comes on if the RH edges up into dangerous
country, drying out the ambient air mass and thus lowering the RH is often a
good idea.

Regards

Mark MacKenzie 
-- 
Mark MacKenzie, M.A.C. (Queen's)
Conservator, Saskatchewan Western Development Museum
www.wdm.ca
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> From: Diana Zlatanovski <[log in to unmask]>
> Reply-To: Textile Conservators <[log in to unmask]>
> Date: Thu, 16 Nov 2006 11:05:42 -0600
> To: [log in to unmask]
> Subject: Re: Textile storage conditions
> 
> 
> Hello
> I manage a collection of textiles.  The HVAC system in our storage
> areas is programmed to keep the temperature between 60 and 65 degrees. 
> Often, it is on the low end of that.  I've always been taught that
> between 68 and 72 degrees is, in general, the ideal temperature for
> collections storage.  Can anyone tell me if the lower range is for any
> reason more appropriate for textiles?  Or if it is detrimental to them?
> 
> Thanks,
> Diana
> 
> *******************
> Diana Zlatanovski
> Assistant Curator
> 
> Helen Louise Allen Textile Collection
> University of Wisconsin
> 1300 Linden Drive
> Madison, WI 53706-1575
> (608) 262-1162
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