3M L-905 Installation instructions

L-905 - Disassembly
© 3M June 2006. All rights reserved.
3M™ Helmet L-905 with Wide-view Faceshield
and Welding Shield
Disassembly
1) The L-114 is the Reinforced Chin Strap. The L-114 chin strap must be
used in the L-700 and L-900 Series Headgear in order to comply with
ANSI Z89.1-2003 Protection from Side Impacts. Replace the chin strap
when it is worn, torn or damaged. To remove it:
a. Unscrew the L-145 Knobs.
b. Remove the components of the L-146 Welding Knob and Pivot Kit.
c. Remove the chin strap attachment plate from the pocket that
contained the cam clip.
2) The L-125 is the Flame Retardant Shroud made from Nomex®
Material, the L-126 is the Inner Shroud and the L-127 is the Leather
Welding Shroud. Replace either shroud whenever it is worn excessively
or anytime it is torn. To remove it:
a. Hold the headgear upside down.
b. Lift the 3M™ Scotchmate™ flap on the left side of the shroud.
c. With a flat-blade screwdriver, loosen the hose clamp until the
shroud assembly can be slipped off the headgear.
d. The L-127 leather welding shroud has an inner shroud (L-126) that
can be zipped out for washing.
Nomex is a registered trademark of E.I. Dupont.
3) The L-153 is the Welding Shield. It should be replaced when it is
damaged. To remove it:
a. Unscrew the L-145 Welding Knobs on either side of the welding
shield and remove them from the cams.
b. Remove the welding shield.

L-905 - Disassembly
© 3M June 2006. All rights reserved.
c. This is the point at which the 3M™ Helmet L-905 can be
converted to a 3M™ Helmet L-905 with Wide-view Faceshield.
To make the headgear into a wide-view faceshield:
i. Place an L-130 Wide-view Faceshield assembly onto the
headgear.
ii. Use an L-141 Knob and Pivot Kit to secure it in place.
iii. The user instructions for the wide-view faceshield
configuration should then be used. Please refer to the user
instructions for additional information on the wide-view
faceshield configuration.
Instructions for the 3M™ Helmet L-905 in welding mode – continued
4) The welding stack is a series of products that make up the welding
shade glass. To remove them:
a. Gently pull the wire clip toward the faceshield chin until it is out of
the two slots in the lens frame, then pivot it up out of the way.
b. Carefully remove the parts in the lens stack.
c. The Shade Glass Welding Stack consists of:
i. The L-162 Safety Plate. The safety plate should be
replaced when it is damaged or missing.
ii. The next piece in the stack is a shade glass. This is not a 3M
part, but it can be purchased at a welding supply store in the
shade desired. It should be a standard 4 ½ inches by 5 ¼
inches welding shade glass.
iii. The L-149 is a Fiber or Plastic Gasket Spacer. The spacer
should be replaced when it is damaged or missing.
iv. The L-142 is a Welding Gasket. It should be replaced when
it is damaged or missing.
v. The L-152 is a Cover Plate. It should be replaced when it is
damaged or missing.
vi. The L-147 is the Welding Lens Retainer Clip. It should be
replaced when it is damaged or missing.

L-905 - Disassembly
© 3M June 2006. All rights reserved.
d. The Electronic Lens Welding Stack consists of:
i. The L-156 Electronic Lens and Adapter for use with the
electronic lens assembly only. It should be replaced when it
is damaged or missing.
ii. The L-142 is a Welding Gasket. It should be replaced when
it is damaged or missing.
iii. The L-152 is a Cover Plate. It should be replaced when it is
damaged or missing.
iv. The L-147 is the Welding Lens Retainer Clip. It should be
replaced when it is damaged or missing.
5) The L-131 is the Wide-view Lens. The lens should be replaced
immediately when excessively scratched or anytime it is cracked, crazed
or does not stay seated. To remove the wide-view lens:
a. Turn all four L-shaped latches a quarter-turn (all the way against
their stops), so they point toward the bottom edge of the faceshield.
b. Flex the lens inward so it is free of the four latches in the wide-view
faceshield frame. Lift the lens from the frame while sliding it out
from under the lower post.
6) The L-136 is the Cam Spring Set. The cam spring set should be
replaced when the faceshield will no longer stay in the up or down
position or when the faceshield is loose in the closed position. The
springs should only be removed if damaged and should not be removed
for cleaning. To remove the cam spring set:
a. Insert a flat blade screwdriver under the spring and lift the spring
out.
7) The L-134 is the Latch Kit. Replace the latches when they are broken
or missing. Do not use the headgear until the latches are in place. To
remove the latches:
a. Use a pliers to grasp the base of the L-shaped latch.
b. Pull forcefully on the latch until it is removed.

L-905 - Disassembly
© 3M June 2006. All rights reserved.
8) The L-113 is the Head Suspension. Replace the head suspension
when it is damaged or broken or the ratchet will not tighten. To remove it:
a. Turn the headgear upside down.
b. Remove the head suspension by pulling out the four mounting clips
that hold it into the bottom edge of the headgear.
c. To remove the L-117 Hanger Suspension from the headband, turn
the four ladder tabs a quarter-turn, then pull them out of the slots in
the headband.
9) The L-116 is the Head Pad. Replace the head pad when it is
excessively dirty or damaged. To remove it:
a. Pull it out of the four slots in the hanger suspension.
10) The L-115 is the Sweat Pad. Replace it when the foam on the sweat
pad begins to degrade or the pad gets dirty or damaged. To remove it:
a. Release the three snaps that are located around the headband.
11) The L-163 is the Foam Liner. It should be replaced when parts are
missing or the liner is damaged by exposure to solvents or excessive
heat. To remove it:
a. Remove the complete L-113 Head Suspension.
b. Lift the foam liner out of the headgear.
12) The L-950 is the Helmet Shell. The helmet shell should be replaced if it
is cracked and/or damaged by contact with solvents.
13) The L-133 is the protective Lens Cover. Lens covers can be ordered in
packs of 100 or 25.
a. Up to 5 lens covers can be placed on the lens, one at a time. When
the top cover gets dirty, peel it off to reveal a clean cover.
b. The lens cover closest to the lens should not be removed in the
work area where your lens can get dirty.

L-905 - Disassembly
© 3M June 2006. All rights reserved.
14) The L-183 is the Headgear Cover Accessory. It is an optional
accessory which provides a means of protection against buildup of
particulate on the surface of the headgear shell. It should be replaced if it
is ripped, torn, the stitching is worn, the seams are frayed or holes are
found in it. To remove it:
a. Pull it off the headgear.
b. Remove the breathing tube and pull the headgear cover off the
breathing tube.
15) The L-182 is the Air Deflector Accessory. The L-182 is an optional
accessory which allows the redirection of the airflow towards the face. If
used, the air deflector should be replaced if it is damaged or missing. To
remove it:
a. Pull it off of the front of the headgear shell.