Hmmm, Ashok , once i did build a smt switch mode assembly plant from untreated planed pine . owner insisted, i agreed (know some classy labs in Nippon crafted that way too) 1 All coats were deemed out right from start . Doesn't look quite as new after 5 years, but still the functionality of antistatic (not dissipative); humidity , work surface, safety, etc. aspects works flawlessly . When you say enamel ; that from my ol skool means ceramic ; however in the woody case I doubt you bake the "enamel" at 800+'C . Therefore yo' guilty of naked plastic static generator (apply fox tail for validations) In that case 'd go for one of (desco) hand static meters and check : i'd bet you have a charge sitting there . Chain dragging Metal trolleys are more common, with dissisipative floor that is (as you know) Quick fix is dissipative rubber mat , grounded . Can't understand why don't you treat side table same as main table. In this case the auditor is correctly gunning after yo 2 wOOdie slide is fine as long as the varnish (oil preferable, plain planed ply better) does not in function as charged plastic . 3 Natural bristle in wood proved fine , carbon bristles earthed are optional luxuries found at intel's washrooms 4 This one's more interesting : the reels are too often plastic, often my geiger got surprising beeb in areas unexpected . Chained metal optimal (dissipation, not only antistatic desirable); notwithstanding with RH above 50% you have none of above worries. Or use woodie stands with earthed metal rods as back support ; the wood/metal(may be SSteel in your parts of world)combinations can be very good on all counts: looks/cheap/dissipative/etc. The modern melamines (discount clean room likes) habits converted with horrendous costs back to dissipations test my sanity way too often. cu paul -----Original Message----- From: Ashok Dhawan [mailto:[log in to unmask]] Sent: Friday, 10 March 2000 4:18 To: [log in to unmask] Subject: [TN] Use of wood in PCB Assembly ?? ESD ?? I have a question (s) on ESD- all related to use of wood in a typical PCB Assembly line: 1. How a wooden mini stool if used for holding tote box ( card board with static protecive coat, black color) can affect static sensitive devices inside the tote box / shipping tubes/bags/ PCB assemblies parially bilt ? The wooden stool sits besides operators seat and operator is wearing wrist strap and attached to grounded table. The point of contension is : Wooden mini-table is coated with enamel paint. What kind of mini table / stool is used in general ? 2. To manual assembly, if woodem slide is used , can it affect components being hand inserted ? Wood is varnished but no enamel paint on this ? 3.For spot cleaning, if brushes with wooden handles are used ? What if bristles of brush are made of Nylon/plastic material ? - Assumption is that brush is soaked in solvent ISO-Propyl when used for cleaning. 4.For storage of Tape feeders on wooden stands -Partially used tapes carrying components on tape feeders. Can a wooden feeder stands affect ? It might appear 4 questions in one, I will appreciate answers toching all aspects as mentioned above. Thanks in advance. -- Ashok Dhawan P.Eng Engineering C-Mac Electronic Systems Inc. 1455 Mountain Avenue Winnipeg, Manitoba R2X 2Y9 Canada Phone: (204) 631-7208 Fax: (204) 631-7294 E-mail: [log in to unmask] www.cmac.ca ############################################################## TechNet Mail List provided as a free service by IPC using LISTSERV 1.8c ############################################################## To subscribe/unsubscribe, send a message to [log in to unmask] with following text in the body: To subscribe: SUBSCRIBE TECHNET <your full name> To unsubscribe: SIGNOFF TECHNET ############################################################## Please visit IPC web site (http://www.ipc.org/html/forum.htm) for additional information. If you need assistance - contact Keach Sasamori at [log in to unmask] or 847-509-9700 ext.5315 ##############################################################