Basic Manual
M1 LGDV
Positive Pressure
Lung Governed Demand Valve
Order No.: D2018702-EN/00
MSA Europe GmbH
Schlüsselstrasse 12
8645 Rapperswil-Jona
Switzerland
www.MSAsafety.com
1 Safety Regulations
1.1 Correct Use
The M1 LGDV, in this manual also referred to as device, is a lung governed
demand valve for a Compressed Air Breathing Apparatus or Compressed
Airline Breathing Apparatus. It is connected between compressed air supply
and full face mask and controls the inhaled air.
The M1 lung governed demand valve series is only permitted for specific
system components.
WARNING!
The device is not an independent breathing apparatus. It must be used
exclusively mounted on a full face mask and an SCBA / CABA.
The device is not suitable for underwater diving.
WARNING!
This product is supporting life and health. Inappropriate use, maintenance
or servicing may affect the function of the device and thereby seriously
compromise the user‘s life.
Before use, the product operability must be veried. The product must not
be used if the function test is unsuccessful, it is damaged, a competent
servicing/maintenance has not been made, genuine MSA spare parts
have not been used..
1.2 Liability Information
MSA accepts no liability in cases where the device has been used
inappropriately or not as intended. The selection and use of the device are
the exclusive responsibility of the individual operator.
Product liability claims, warranties and guarantees made by MSA with
respect to the device are voided, if it is not used, serviced or maintained in
accordance with the instructions in this manual.
1.3 Series
This manual applies to the following lung governed demand valves from the
M1 LGDV series:
AS (push to connect / quick connect)
• M1-AS LGDV, short
• M1-AS LGDV, long
• M1-AS LGDV, fix
M45x3 (threaded version)
• M1-AE LGDV M45x3, short
• M1-AE LGDV M45x3, long
• M1-AE LGDV M45x3, fix
ESA (push to connect / quick connect according to DIN 58600)
• M1-ESA LGDV, short
• M1-ESA LGDV, long
AS-B (push to connect / quick connect with Bypass)
• M1-AS-B LGDV, short
• M1-AS-B LGDV, long
Explanations on model designation
AS: Positive pressure, plug-in connection, suitable for full face
masks PS-MaXX
AE: Positive pressure, thread connection M45x3 according to
DIN EN 148-3, suitable for full face masks -PF
ESA: Positive pressure, plug-in connection according to DIN 58600,
suitable for full face masks ESA
AS-B: Positive pressure, bypass for constant air flow
2 Description
2
3
4
5
6
8a 8b
7
9
M1-AS LGDV M1-AE LGDV M1-ESA LGDV M1-AS-B LGDV
1 Flush button 6
2 Cover 7
3 Positive pressure spring 8a
4 Diaphragm 8b
5 Valve assembly (inclusive housing) 9
Dust cap
Medium pressure hose
Short / long version for coupling
Fixed version
Bypass
3 Use
3.1 Preparing the Device
WARNING!
The lung governed demand valve may only be put into use in a fully main-
tained and tested condition. If malfunctions or defects are noticed prior to
use, do not use the lung governed demand valve under any circumstan-
ces. Failure to follow this warning can result in serious personal injury or
death.
Get the apparatus checked and repaired by an authorised service centre.
Switching off the Device
Before connecting the device to medium pressure, in order to prevent
accidental air delivery, push the red operating button to switch off the device.
3.2 Connecting the Device
1. Insert plug-in nipple of the device into the coupling of the medium
pressure hose of an approved SCBA until it distinctly snaps into place (not
for fixed LGDV).
2. Don full face mask and perform tightness check according to the mask
operating manual.
3. Open cylinder valve(s) fully.
4. Screw the device into the mask (M1-AE) or insert it into the adapter of the
mask until it distinctly snaps into place (M1-AS, M1-AS-B, M1-ESA).
Support during Donning
MSA recommends that the device must be attached to the mask and the
connection inspected by a second person.
3.3 Putting the Device into Operation
To activate the device, inhale once forcefully or push the flush button.
WARNING!
When using the ush button, the compressed air consumption increases.
In case of an emergency, push the flush button to flush out smoke
and gases from the mask.
3.4 Switching off the Device
To switch off the device, push red operating button until stopper.
