13
• With the airflow indicator in a vertical position, ensure that the bottom of the floating ball rests at, or above, the
minimum flow mark for the ‘letter’ representing your ‘Zone’ (Fig. 14-2). Airflow indicator must be in the vertical
position for an accurate reading.
The airflow indicator is graduated into different ‘zones’ based on air density, which is based on elevation and ambient
temperature. To determine your zone, determine the elevation and temperature for the environment where you are
conducting the airflow check. See your supervisor if you are not certain of these values. Find the zone where your
elevation and temperature intersect on the chart supplied with the airflow indicator (Chart 1).
Fig. 14-1 – Attaching airflow indicator
Fig. 14-2 – Checking airflow
°C
-10 0
10 20 30 40 50
m
14 32 50 68 86 104 122
-305 -1000 A
B
C
D
E
F
G
0
0
B
C
D
E
F
G
H
305 1000
C
D
E
F
G
H
I
610 2000
D
E
F
G
H
I
J
915 3000
E
F
G
H
I
J
K
1219 4000
F
G
H
I
J
K
L
1524 5000
G
H
I
J
K
L
M
1829 6000
H
I
J
K
L
M
N
2134 7000
I
J
K
L
M
N
O
2439 8000
J
K
L
M
N
O
P
2744 9000
K
L
M
N
O
P
Q
3048 10000 L
M
N
O
P
Q
R
3353 11000 M
N
O
P
Q
R
S
3658 12000 N
O
P
Q
R
S
T
3963 13000 O
P
Q
R
S
T
U
4268 14000 P
Q
R
S
T
U
V
4573 15000 Q
R
S
T
U
V
W
4877 16000 R
S
T
U
V
W
X
5182 17000 S
T
U
V
W
X
Y
°F
ft
Chart 1 – Determining airflow indicator zone based on elevation and temperature. Recommended use temperature
range: 23°F to 131°F (-5°C to 55°C). Recommended elevation: -328 feet to 16404 feet (-100 meters to 5000 meters).
Contact 3M Technical Service if intended use may be outside of these ranges.
NOTE:
If the airflow indicator ball fails to rise at or above the minimum flow level, do not use the motor/blower unit. Refer to
the 3M™ Versaflo™ Powered Air Purifying Respirator TR-800 “Troubleshooting” guide or contact 3M Technical Service.
7. Low flow alarm check: Check the low airflow alarm by simulating a low airflow condition. With the motor/blower on:
• Remove the airflow indicator and tightly cover the outlet of the motor/blower with the palm of your hand. The motor
should automatically speed up, attempting to compensate for the low airflow condition.
