At 02:39 14-07-98 +0100, ard_at_p850ug1.demon.co.uk (Tony Duell) wrote:
--snip--
>I believe something like this does exist. A Kennedy winchester service
>manual mentions a plugged hole on the HDA cover as being a port for a
>particle counter which you use to tell you when to change the breather
>filter.
This port allows one to check performance of the HEPA filter in the air
moving system.
>I don't know how it works. For high particle counts (like your vacuum
>cleaner), I would guess you could use light scattering. I can't believe
>that would work at class 100 levels, though.
Light scattering is how most particle counters work and indeed they are
sensitive in the range below class 10.
--Chris
-- --
Christian Fandt, Electronic/Electrical Historian
Jamestown, NY USA
Member of Antique Wireless Association
URL:
http://www.ggw.org/freenet/a/awa/
Received on Tue Jul 14 1998 - 09:36:29 BST