[Bldg-sim] productivity of office workers as function of temperature and co2 concentration

Jim Dirkes jim at buildingperformanceteam.com
Mon Jun 11 11:11:00 PDT 2012


Without having read the documents Nick is referring to...

Recall that CO2 is a surrogate indicator of air quality.  It was never
intended to indicate that the atmosphere was unhealthy, just that it might
be unhealthy.

>From memory:

.         the original research done by ASHRAE varied outdoor air
ventilation rates in a test studio which was occupied by real people.  

.         The people were surveyed at random times for their perception of
comfort.  (Since the temperature and humidity did not vary, "comfort" was
more akin to perception of "freshness" of the air.)

.         Survey results were analyzed for correlation with ventilation
rates that existed at the time corresponding to the survey

.         There was a correlation between ventilation rate and comfort

.         The correlation was presented as ppm of CO2 assuming:

o    a specific background / outdoor air concentration (350ppm, I think)

o   sedentary people were the only generators of CO2

 

So, it seems to me that it's a BIG stretch to try to correlate productivity
with CO2.

 

The Building Performance Team
James V. Dirkes II, P.E., BEMP , LEED AP
1631 Acacia Drive NW
Grand Rapids, MI 49504
616 450 8653

 

From: bldg-sim-bounces at lists.onebuilding.org
[mailto:bldg-sim-bounces at lists.onebuilding.org] On Behalf Of Nick Caton
Sent: Monday, June 11, 2012 1:20 PM
To: Struck Christian HSLU T&A; 'bldg-sim at lists.onebuilding.org'
Subject: Re: [Bldg-sim] productivity of office workers as function of
temperature and co2 concentration

 

This sounds like the beginnings of a an elaborate/scientific office prank
with the boss's thermostat. =)

 

In all seriousness, I believe the effect of ambient temperatures are pretty
established.  Here's a brief article in layman's terms and a pretty graph:  

http://productivity-science.com/blogen/post/What-temperature-is-best-for-you
r-productivity.aspx

 

Here's a research paper cited in the previous link with more info: 

http://escholarship.org/uc/item/45g4n3rv#page-8

 

I'm not certain whether there is anything in the realm of IEQ/CO2 monitoring
that establishes a clear causal effect on task productivity similar to the
above.  

 

Here's a paper that attempts to connect the dots between ventilation rates
(2 levels) and annual sick-leave accrual for office workers:
http://www.google.com/url?sa=t
<http://www.google.com/url?sa=t&rct=j&q=milton%20risk%20of%20sick%20leave%20
associated%20with%20outdoor%20air%20supply%20rate%2C%20humidification%2C%20a
nd%20occupant%20complaints&source=web&cd=3&ved=0CFoQFjAC&url=http%3A%2F%2Fww
w.e-co.uk.com%2FRecirc-Milton2000.pdf&ei=xCbRT5ujBeWL2AXWw4WxDw&usg=AFQjCNFB
vi_nWYBGbwn_f6NV3hxRHn7MtA>
&rct=j&q=milton%20risk%20of%20sick%20leave%20associated%20with%20outdoor%20a
ir%20supply%20rate%2C%20humidification%2C%20and%20occupant%20complaints&sour
ce=web&cd=3&ved=0CFoQFjAC&url=http%3A%2F%2Fwww.e-co.uk.com%2FRecirc-Milton20
00.pdf&ei=xCbRT5ujBeWL2AXWw4WxDw&usg=AFQjCNFBvi_nWYBGbwn_f6NV3hxRHn7MtA

 

The "dollars lost"  economical argument extrapolated in the conclusions
looks dramatic, but even if we accept CO2 concentrations are tied directly
to sick leave hours.  that's not quite the same thing as a direct
productivity effect (i.e. my co-worker breathing heavily is preventing me
from doing my work).

 

If you were to combine the above studies into a single model I suppose you
reasonably establish a linear CO2-concentration-factor curve to apply
against an ambient temperature curve to come up with a combined productivity
effect.  I might sooner look further for something akin to the temperature
study however.

 

~Nick

 

 

cid:489575314 at 22072009-0ABB

 

NICK CATON, P.E.

SENIOR ENGINEER

 

Smith & Boucher Engineers

25501 west valley parkway, suite 200

olathe, ks 66061

direct 913.344.0036

fax 913.345.0617

www.smithboucher.com 

 

From: bldg-sim-bounces at lists.onebuilding.org
[mailto:bldg-sim-bounces at lists.onebuilding.org] On Behalf Of Struck
Christian HSLU T&A
Sent: Tuesday, June 05, 2012 9:09 AM
To: 'bldg-sim at lists.onebuilding.org'
Subject: [Bldg-sim] productivity of office workers as function of
temperature and co2 concentration

 

Hey all

 

Can you point me towards a model which describes the office worker
productivity as a function of temperature AND co2 concentration? 

 

Many thanks in advance!

 

Christian

 

 

 

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.onebuilding.org/pipermail/bldg-sim-onebuilding.org/attachments/20120611/b2a0f717/attachment-0002.htm>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: not available
Type: image/jpeg
Size: 1459 bytes
Desc: not available
URL: <http://lists.onebuilding.org/pipermail/bldg-sim-onebuilding.org/attachments/20120611/b2a0f717/attachment-0002.jpeg>


More information about the Bldg-sim mailing list