The most serious cases against WD-40 involved cans that exploded after touching electrical parts or wires,            
according to documents obtained by Bloomberg Business News through a Freedom of Information Act request.
News / Reviews WD-40 bursts into flames
WD-40 bursts into flames lubricating fan!
Dan Horton of Ocean Springs, Miss., was lubricating a wall fan with WD-40 in November  1988 when the can touched a live wire. The container burst into flames, burning Horton's    
18-month-old daughter Lauren.

WD-40 explodes touching amp meter! 
In Jackson, Miss. William Sharp was    spraying a speedometer cable in  his truck   when the can touched an amp meter. The       can exploded, trapping his wife Susie --who survived--in the flaming cab.
Firearms - you should never use WD-40 to clean or maintain firearms. It's hygroscopic and will
attract moisture to the firearm which will result in rust.

Drive chains of any type - because WD-40 isn't a lubricant it really will not work well on Drive        
chains of any type.

Gears of any type - WD-40 doesn't have enough lubrication affect to be useful on any type of gearing
only specified gear lubricants should be used.

Never use WD-40 on door hinges or anything you want to keep clean. It attracts dirt and dust. It will turn 
your hinge pins black.

WD-40 will ruin a bike chain and the gears wear out quicker. It washes the dirt in, the dirt acts as an abrasive and not a lubricant.

​For the same reason you wouldn't use it on door hinges, it should never be used for chair and sofa mechanisms. Because WD-40 attracts dust and turns things black, over time that dirt accumulation within the moving parts will build up and eventually start to fall off onto carpeting creating a terrible black mess that is nearly impossible to remove.
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When should I not use WD-40?
News Flash!!

  Glide is now being used by 
  General Electric Train Division 
  for lubricating and cleaning engines! 
Glide's non-conductive formula will not         s   hort-circuit electrical connections. 
Glide is a semi finalist in the Good Housekeeping and HSN Seal Contest! 

SAN DIEGO - Leon Fields was squirting
WD-40 under his Winnebago camper to stop corrosion, one  of the advertised "1,000 uses"    for the spray lubricant, when the can touched a live wire and another piece of metal and burst    into a fiery ball   of oil and propane."It just  spread like napalm," said Fields, a 58-year old math teacher who was burned over 24% of his body in the accident.

As seen on QVC and HSN
Glide will be on                  with Kevin Harrington from shark tank!