[CAUT] fire extinguisher dust

[Horace Greeley]

Hi,

At 09:19 AM 5/2/2005, you wrote:
>At 09:51 AM 5/2/2005 -0500, you wrote:
>
>>DO NOT TOUCH the dust.
>
>What IS the stuff, anyway? Caustic? Acid? Fine particles which lodge in 
>lungs?

It really depends on what class of agent was used in the extinguisher (A, 
AB, ABC....etc).  Different agents have different properties.  Many are 
relatively harmless to humans - in the quantity and density used in 
extinguishers.  Some contain compounds which have various deliterious 
effects on pianos, corrosive agents, yes; but even more likely stuff that 
is, over time, abrasive and/or gummy (depending on humidity).

If the stuff really got far down into the action/etc, that is, if it seemed 
to have been sprayed (under pressure) you may wind up with much less 
trouble simply rebuilding the action.  I have found that the dust very 
quickly works its way into key and flange bushings and that there does not 
seem to be a good way to get rid of it.  At the same time, that really is 
something of a worst-case scenario...

If you can, check to see what class fire extinguisher was used and then see 
if you can get an MSDS from the manufacturer and/or supplier; at the same 
time asking them about corrosive and abrasive agents.

Sorry I do not have time for a more complete reply.

Best.

Horace