Fume hood language

[Allen Doyle]

Hello Green Labbers,

Problem: Fume hood language is inaccurate; 

Solution:  Would it be helpful to more accurately call them "fume hood systems"?

Does it matter?  Not sure.  Fume hoods are convenient icons of energy waste.  The basic message of "close the darn hood" still applies, as closed hoods are always safer than open ones. It's not always apparent which hoods are constant vs. variable air flows, and which rooms' air flow is dominated by fume hoods.  Not all rooms are "hood driven."

Background:

          In many of our slide presentations we say that a fume hood "device" uses three times as much energy as a house.  The issue is that a fume hood is just a metal box with a window, with or without some aerodynamic features, and it does not by itself consume energy.  It's energy use depends on the fans, dampers, electronics, heating and cooling efficiencies, etc, which are all part of a mechanical system, mostly hidden above the ceiling. 

--

            805 729 1581 (c)

            MS Chemical Oceanography; CEM; LEED AP

In the future, people will bring grocery carts into the store from the parking lot.

            Keep Thinkin' UPstream!

[Barry Reid]

Hi Allen,

Just curious… in the UK we refer to them as VAV (variable air volume) and CAV (constant air volume)… the former being our preference when setting up new labs or refurbing labs as the energy savings are immense.

What nomenclature do you tend to use over the other side of the pond? Is it different over there? (We find the terminology regarding air flows on MSC’s quite different over here).

Best regards,

Barry.

Sent from my iPhone

On 30 Nov 2022, at 20:17, Allen Doyle <adoyl...@gmail.com> wrote:



--
--
** Please remember to change the subject header if you change topics **
---
You received this message because you are subscribed to the Google Groups "Green Labs Planning" group.
To unsubscribe from this group and stop receiving emails from it, send an email to green-labs-plan...@googlegroups.com.
To view this discussion on the web visit https://groups.google.com/d/msgid/green-labs-planning/CAL5tagEEZp%3D7aEb6dAiufzcjDBqjHFgqoUXexGcFzH7wT4vibQ%40mail.gmail.com.

[Allen Doyle]

Hi Barry,

           The abbreviations are the same here, but the VAV vs. CAV is determined above the ceiling where you can't see it. Either way the cupboard, or the hood, still looks like a metal box with a window to the average user.  My point is to help people understand that the metal box is just the collector part of a potentially complex system.  My question is, "Does adding "system" to "fume hood" make a difference to the novice user, or just confuse them?"

            Not all VAV hoods save energy if they are a single hood in a large room, for example, where general exhaust exceeds fume hood exhaust.  Sometimes, a CAV hood may be preferable for simplicity, which can be part of resilience.

            Cheers,

                   Allen

To view this discussion on the web visit https://groups.google.com/d/msgid/green-labs-planning/ED1D773B-B519-4EF6-AF31-ABC111EAC609%40gpescientific.co.uk.

[Barry Reid]

Hi Allen,

Thanks for clarifying… yes - I agree not all VAV’s save money… (but we tend to be involved in projects that have a minimum of 10 units up to a max of about 200 for an entire Chemistry building)… we also inform people that recirc fume hoods also have their place (if the MSDS’s will allow and an appropriate filter set is available - OS/H+ etc - but this can get pricey replacing filters as they are often easily saturated)…. Some clients also get confused between MSC’s and Fume hoods - I once had to shut a lab down when a young post doc was found to be handling botulinum in a fume hood!  Eeek! 

Best regards,

Barry.

Sent from my iPhone

On 30 Nov 2022, at 20:39, Allen Doyle <adoyl...@gmail.com> wrote:



To view this discussion on the web visit https://groups.google.com/d/msgid/green-labs-planning/CAL5tagGRCLO-bUbQz0Z4q9yfoBTpOqyki6%3DFG4d7uU%2B4yF2%3DSA%40mail.gmail.com.