HD32.1
- 9 -
V2.1
•
Reduce directly the thermal stress on the workplace being examined;
•
Proceed to a detailed analysis of the thermal stress.
In the following table are reported the thermal stress index WBGT limit values as provided for by
ISO 7243:
METABOLIC RATE, M
WBGT LIMIT VALUE
METABOLIC
RATE CLASS
RELATIVE TO A
UNIT AREA OF
THE SKIN
W/m
2
TOTAL (FOR A
SKIN SURFACE
AVERAGE AREA
OF 1.8 m
2
)
W
PERSON ACQUAINTED TO THE
HEAT
°C
PERSON NOT ACQUAINTED TO
THE HEAT
°C
0
(RESTING)
M
≤
65
M
≤
117
33
32
1
65 < M
≤
130
117 < M
≤
234
30
29
2
130 < M
≤
200
234 < M
≤
360
28
26
3
200 < M
≤
260
360 < M
≤
468
DEAD AIR
25
NON DEAD AIR
26
DEAD AIR
22
NON DEAD AIR
23
4
M > 260
M > 468
23
25
18
20
NOTE – THESE VALUES HAVE BEEN DETERMINED BY USING A MAXIMUM REFERENCE RECTAL TEMPERATURE OF 38 °C
FOR THE PEOPLE BEING EXAMINED.
In order to calculate the WBGT index, the following probes should be connected:
•
The natural ventilation wet bulb temperature probe.
•
The globe thermometer probe.
•
The dry bulb temperature probe, if the measurement is performed with solar
radiation.
In order to measure the WBGT index, you should refer to the following regulations:
•
ISO 7726
•
ISO 7243
2.1.2 Turbulence Intensity (Tu index)
Turbulence Intensity:
Local turbulence intensity percentage, defined as the ratio between the local
wind speed standard deviation and the local air average speed (ISO 7726):
100
×
=
a
v
SD
Tu
where:
v
a
= average local wind speed
SD
= local wind speed standard deviation
(
)
∑
=
−
⋅
−
=
n
i
a
a
v
v
n
SD
i
1
2
1
1
From the turbulence calculation, knowing the average values of the local wind speed and
environment temperature, you can get the
DR
(Draught Rating), according to ISO 7730:
(
) (
)
(
)
14
,
3
37
,
0
05
,
0
34
62
,
0
+
⋅
⋅
⋅
−
⋅
−
=
Tu
v
v
t
DR
a
a
a
Summary of Contents for HD32.1
Page 6: ...HD32 1 6 V2 1 Thermal Microclimate HD32 1...
Page 78: ...HD32 1 78 V2 1 MIN 350 MAX 1020 120 AP471 S4...
Page 106: ...HD32 1 106 V2 1 Moderate Environment Norm ISO 7730...
Page 107: ...HD32 1 107 V2 1 Moderate Environment Norm ISO 7730...
Page 108: ...HD32 1 108 V2 1 Moderate Environment Norm ISO 7730...
Page 109: ...HD32 1 109 V2 1 Moderate Environment Norm ISO 7730...
Page 110: ...HD32 1 110 V2 1 Moderate Environment Norm ISO 7730...
Page 111: ...HD32 1 111 V2 1 Moderate Environment Norm ISO 7730...
Page 112: ...HD32 1 112 V2 1 12 2 WARM ENVIRONMENT Norm ISO 7243 Norm ISO 7243...
Page 113: ...HD32 1 113 V2 1 Warm Environment Norm ISO 7243...
Page 114: ...HD32 1 114 V2 1 Warm Environment Norm ISO 7243 Norm ISO 7243...
Page 115: ...HD32 1 115 V2 1 Warm Environment Norm ISO 7243...
Page 116: ...HD32 1 116 V2 1 Warm Environment Norm ISO 7243...
Page 117: ...HD32 1 117 V2 1 Warm Environment Norm ISO 7243...
Page 118: ...HD32 1 118 V2 1 12 3 DISCOMFORT ANALYSIS Norm ISO 7730 Norm ISO 7730...
Page 119: ...HD32 1 119 V2 1 Discomfort Analysis Norm ISO 7730...
Page 120: ...HD32 1 120 V2 1 Discomfort Analysis Norm ISO 7730...
Page 121: ...HD32 1 121 V2 1 Discomfort Analysis Norm ISO 7730...
Page 122: ...HD32 1 122 V2 1 Discomfort Analysis Norm ISO 7730...
Page 123: ...HD32 1 123 V2 1 Discomfort Analysis Norm ISO 7730...
Page 124: ...HD32 1 124 V2 1 Discomfort Analysis Norm ISO 7730...
Page 125: ...HD32 1 125 V2 1 12 4 HOT ENVIRONMENT Norm ISO 7933 Norm ISO 7933...
Page 126: ...HD32 1 126 V2 1 Hot Environment Norm ISO 7933...
Page 127: ...HD32 1 127 V2 1 Hot Environment Norm ISO 7933...
Page 128: ...HD32 1 128 V2 1 Hot Environment Norm ISO 7933...
Page 129: ...HD32 1 129 V2 1 Hot Environment Norm ISO 7933...
Page 130: ...HD32 1 130 V2 1 Hot Environment Norm ISO 7933...
Page 131: ...HD32 1 131 V2 1 Hot Environment Norm ISO 7933...
Page 132: ...HD32 1 132 V2 1 12 5 COLD ENVIRONMENT Norm ISO 11079 Norm ISO 11079...
Page 133: ...HD32 1 133 V2 1 Cold Environment Norm ISO 11079...
Page 134: ...HD32 1 134 V2 1 Cold Environment Norm ISO 11079...
Page 135: ...HD32 1 135 V2 1 Cold Environment Norm ISO 11079...
Page 136: ...HD32 1 136 V2 1 Cold Environment Norm ISO 11079...
Page 137: ...HD32 1 137 V2 1 Cold Environment Norm ISO 11079...
Page 138: ...HD32 1 138 V2 1 Cold Environment Norm ISO 11079...
Page 139: ...HD32 1 139 V2 1 Cold Environment Norm ISO 11079...
Page 140: ...HD32 1 140 V2 1 12 6 PHYSICAL QUANTITIES...
Page 153: ...HD32 1 153 V2 1 NOTES...
Page 154: ...HD32 1 154 V2 1 NOTES...
Page 155: ......