SAFE WORK PRACTICES
WORK WARM-UP SCHEDULE – OUTDOOR ACTIVITIES Page 1 of 2
*This information does not take precedence over OH&S.
All employees should be familiar with the Saskatchewan Employment Act and the OH&S Regulations.
Information applies to any four (4) hour period. Warm-up breaks are assumed to provide ten (10) minutes in a
warm environment.
Air TemperatureSunny Sky
C0
Approx.
-26 to -28
-29 to -31
-32 to -34
-35 to -37
-38 to -39
-40 to -42
43 and
below
F0
Approx.
-15 to -19
-20 to -24
-25 to -29
-30 to -34
-35 to -39
-40 to -44
45 and
below
No Noticeable
Wind
Max.
Work
Period
Normal
Breaks
Normal
Breaks
75
Minutes
55
Minutes
40
Minutes
30
Minutes
Number
of Breaks
1
1
2
3
4
8 km/hr Wind
(5 mph)
Max.
Work
Period
Normal
Breaks
75
Minutes
55
Minutes
40
Minutes
30
Minutes
Number
of Breaks
1
2
3
4
Max.
Work
Period
75
Minutes
55
Minutes
40
Minutes
30
Minutes
Number
of Breaks
2
3
4
24 km/hr Wind
(15 mph)
Max.
Work
Period
55
Minutes
40
Minutes
30
Minutes
Number
of Breaks
3
4
NON EMERGENCY
WORK SHOULD STOP
32 km/hr Wind
(20 mph)
Max.
Work
Period
Number
of Breaks
40
Minutes
30
Minutes
4
5
5
5
5
5
NON EMERGENCY
WORK SHOULD STOP
16 km/hr Wind
(10 mph)
NON EMERGENCY
WORK SHOULD STOP
NON EMERGENCY
WORK SHOULD STOP
NON EMERGENCY
WORK SHOULD STOP
1.
Apply the schedule one step lower for work with limited physical activity. For example, -350C (-300F) with a noticeable wind (step 4), a
worker with a job with little physical movement should have a maximum work period of 40 minutes with 4 breaks in a four-hour period.
2.
If accurate information is not available, the following may be used as a guide for estimating wind velocity. Wind at 8 km/hr (5 mph) will
move a light flag, at 16 km/hr (10 mph) it will fully extend the flag, at 24 km/hr (20 mph) it will produce blowing and drifting snow.
3.
If only the Wind Chill Factor (Watts Per Square Meter) is available, a rough guide for applying it rather than the temperature and wind
velocity factors given above would be: (1) Special warm-up breaks should be initiated at a wind chill of about 1750; (2) All nonemergency work should cease at or before a wind chill of -50.
SAFE WORK PRACTICES
WORK WARM-UP SCHEDULE – OUTDOOR ACTIVITIES Page 2 of 2
COOLING POWER OF WIND ON EXPOSED FLESH EXPRESSED AS AN EQUIVALENT OF TEMPERATURE
Actual Temperature Reading in Celsius
10.0
Est.
Wind
Speed
(KPH)
CALM
8
18
24
32
40
48
56
64
4.4
-1.1
-6.7
-12.2
-17.8
-23.0
-29.0
-34.0
-40.0
-46.0
-51.0
-34.0
-34.4
-50.0
-57.7
-63.3
-66.6
-70.0
-72.2
-73.3
-40.0
-43.8
-56.4
-65.0
-71.1
-75.5
-78.3
-80.5
-82.2
-46.0
-49.4
-63.8
-72.7
-78.8
-83.3
-87.2
-89.4
-91.1
-51.0
-55.5
-70.5
-80.0
-85.0
-91.6
-95.5
-98.3
-100.0
Equivalent Chill Temperature
10.0
8.9
4.4
2.2
0
1.1
-2.2
-2.8
-3.3
4.4
2.8
2.2
-5.6
-7.8
-8.9
-10.6
-11.7
-12.2
-1.1
-2.8
-8.9
-12.8
-15.6
-17.8
-18.9
-20.0
-21.1
-6.7
-8.9
-15.6
-20.6
-23.3
-26.1
-27.7
-28.9
-29.4
-12.2
-14.4
-22.8
-27.7
-31.7
-34.0
-36.1
-37.2
-38.3
-17.8
-20.6
-31.0
-37.8
-39.4
-42.2
-44.4
-46.1
-47.2
-23.0
-26.1
-36.1
-42.7
-47-2
-50.5
-52.7
-55.0
-56.1
-29.0
-32.2
-43.3
-50.0
-55.0
-58.8
-61.6
-63.3
-65.0