70% is better.  99% evaporated too quickly to get into the stuff...  
see below.  For cleaning, 99% is great, but for Cv-19, I believe 70%  
is better - you need to let it dry completely before set your  
assembly on it.  IMHO.
"Between the concentrations of 60% and 90%, Isopropyl alcohol is a  
very effective agent against microbial bacteria, fungi, and  
viruses . ... 70 % IPA solutions are very effective in breaching the  
cell wall fully. Also, the presence of water slows down evaporation  
and increases the surface contact time with the membrane."
On Mar 16, 2020, at 2:13 PM, David Bealer wrote:

> We are using wipes moistened with electronics grade isopropanol  
> (99%) and letting the surface dry, then using our normal mat cleaner.
>
> David Bealer
> Sr. Process Engineer
> office 800-637-2645 x6022   cell 217-474-8760
>
> -----Original Message-----
> From: TechNet <[log in to unmask]> On Behalf Of Gmail - Dick
> Sent: Monday, March 16, 2020 11:32 AM
> To: [log in to unmask]
> Subject: [TN] Sanitizing ESD Workstations
>
> [External Sender]
>
> Some production personnel are concerned with possible Covid-19 at  
> their workstations. Some may have brought Lysol or Clorox or other  
> brand products to work.
> We don’t permit “outside” materials to be used since they may  
> degrade ESD mats, leave corrosive residues, etc.  I can however  
> understand that they have a concern.
> Production personnel wear either disposable or reusable gloves and  
> shouldn’t be touching their face with potentially Pb contaminated  
> gloves.
> Is anyone aware of sanitizing wipes that are safe for ESD  
> workstations?
> Specific name brands should be referred to me off-line to maintain  
> a non-commercial forum.
>
> Dick Krug
> Sparton Electronics
> Brooksville, FL
> [log in to unmask]
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