Metal Removal The  following  paragraphs  provide  guidelines for  removal  of  corrosion  products  without damaging  the  structure.  Removal  of  corrosion that  has  propagated  beyond  these  limits  requires replacement of the part. CADMIUM-PLATED PARTS.— On cad- mium-plated parts, corrosion will be evident as mottling   of   the   plated   surface   with   color ranging  from  light  gray  to  black.  This  is  a function of the cadmium plating to protect the underlying base metal, and no attempt should be made  to  remove  the  discoloration.  The  presence of  exposed  base  metal  in  a  localized  area is   acceptable   and   should   be   protected.   The appearance   of   red   rust   is   cause   for   part replacement. CHROMIUM   AND   NICKEL-PLATED PARTS.— You should polish bright plated parts with a fine Scotchbrite abrasive mat or 500/600 aluminum oxide abrasive cloth. Do not penetrate to the base material. If base material is exposed, it is cause to remove and replace  the affected  part. ALUMINUM  FORGINGS  AND  CAST- INGS.— Metal removal should not exceed 0.005 inch   in   depth.   You   should   apply   chemical conversion coating (alodine) to bare surfaces and repaint them as required. RESTORATION OF FINISH Abrasions  and  isolated  damage  areas  may  be restored using the following procedures: First, mask the area to be treated. You should feather sand the area around the damage with abrasive paper  or  Scotchbrite  mat.  Next,  apply  paint remover or methyl ethyl ketone and wipe the area dry   with   cheesecloth   before   the   solvent evaporates. At this point, if bare metal is show- ing, you should apply alodine and allow it to dry. Finally, apply one coat of primer and two coats of  paint. Special attention should be paid to the use of primers, polyurethane paints, paint removers, and methyl ethyl ketone. They are all flammable and toxic.  Do  not  use  them  near  open  flames  or sparks. Do not allow them to come in contact with your skin or eyes. Their use should be restricted to a well-ventilated area. SAFETY  PRECAUTIONS Safety  precautions  must  be  strictly  observed when working around aircraft equipped with an ejection seat. These safety precautions cannot be overemphasized. Each ejection seat has several ground safety pins. These safety pins are provided on red-flagged lanyards for use at every point of potential danger. They must be installed whenever the aircraft is on the ground or deck, and they must never be removed until the aircraft is ready for flight. The  following  general  precautions  should always be kept in mind: 1. Ejection  seats  must  be  treated  with  the same respect as a loaded gun. 2. Always consider an ejection seat system as loaded and armed. 3. Before you enter a cockpit, know where the ejection seat safety pins are located and make certain of their installation. 4. Only authorized personnel may work on, remove, or install ejection seats and components, and only in authorized areas. Supervisors take note. It has been said that nothing   is   foolproof   because   fools   are   so ingenious. Personal safety for those who work around  ejection  seats  cannot  be  guaranteed; however, a high level of safety can be achieved if  personnel  have  the  proper  attitude,  under- standing   training,   and   adequate   supervision. Unless   proper   maintenance   procedures   are followed explicitly, even the most routine ejection seat maintenance tasks can grow drastically out of  proportion  and  bring  about  an  accident  or injury.  Education  of  the  workers  involved  is  the best assurance for personnel safety. The workers should be made aware of potential hazards and the   proper   means   of   protecting   themselves. Workers should be assigned according to their capabilities. 6-73