(4)Wear foot covers (wing socks) to prevent damage to finish. Failure to
wear foot covers may result in exposing bare metal to attack.
(5)Consider protecting uncontaminated areas by taping down protective mate-rial such as plastic sheets or toweling. Plastic sheeting or toweling
can also be taped over a contaminated area to isolate it while equipment
is being collected for the removal of mercury.
5. Mercury Removal
A. The first action to be taken is to remove all visible mercury without delay.
The following methods of removal are suggested, the more primitive methods
are less effective than those requiring special equipment, but any possible
method should be attempted whereby speed is essential.
(1)Use paper or cardboard troughs to scoop up the mercury.
(2)Use adhesive tape to pick up small droplets.
(3)Use a medicine dropper for globules.
(4)Use a high-powered vacuum cleaner with a trap. See Fig. 1 for a sug-gested method of making a trap.
(5)Use one of the special mercury pickup brushes that attract the mercury.
Foam pads are also commercially available that will pick up mercury.
Refer to par. 6 for details of a suitable brush.
(6)Use the special Hg vacuum cleaner, if available.
WARNING:ALL DETECTABLE MERCURY MUST BE REMOVED FROM THE AIRPLANE.
B. After removal of any visible mercury more sophisticated means must be
employed to ensure that hidden mercury is located and removed. A sensing
device known as a mercury sniffer can be used, or even more effectively, X-
ray pictures can be taken.
C. Where there is evidence of the presence of mercury in joints, between faying
surfaces, or trapped in any way between structural members, they must be
disassembled as necessary to permit complete removal of the mercury.
6. Removal of Mercury Using Brushes
A. A special brush is available made from nickel plated carbon fibers that will
pick up mercury. Refer to par. 7 for the source of supply.
B. A brush made from fine copper wire can also be used to pick up mercury. It
is suggested that a suitable brush could be manufactured locally by using
the fine wires used in domestic flexible electrical cable. The procedure for
using the copper brush is as follows:
(1)Dip the brush in nitric acid (HN03) to clean the wires.
(2)Dip the brush into water to remove the acid.
Volume 1
20-41-00
Page 2
OCT 01/01
CORROSION PREVENTION MANUAL
CORROSION REMOVAL TECHNIQUES
PROCEDURE AFTER MERCURY SPILLAGE
(3)Dip the brush into alcohol to remove the water.
(4)Pick up the mercury with the brush. Mercury adheres to the copper wires
by forming an amalgam. After the brush has collected a quantity of mer-cury it can be shaken off into a suitable container, and the picking up
process continued.
7. Special Equipment 中国航空网 www.aero.cn 航空翻译 www.aviation.cn 本文链接地址：757 防腐手册 CORROSION PREVENTION MANUAL 第二册 一般信息(35)
