/PAF > Radiazioni Ottiche Aritificiali

Calculation of the protective equipment
for welding as a function of the distance

developed by Andrea Bogi, Nicola Stacchini, Iole Pinto -

"USL Toscana Sudest" Tuscany Agency- Public Health Laboratory of Siena

 

UV (S) * W/m2
UVA * W/m2
Blue * W/m2
Distance of measurement m
Distance chosen for calculation m
  USER GUIDE SHOW AN EXEMPLE GMAW_MIG (200 A) PERFORM CALCULATION

* Effective irradiance measured values

  Choose the PPE graduation
for welding
EN 169

Resulting transmission
τ-313 τ-365 τV τA
  Choose the PPE graduation for ultraviolets
EN 170 (1992)

Resulting transmission

τ-313

τ-365

τV

  not attenuated   UNI EN 169   UNI EN 170
UV (S) [W/m2]
Percentage of ELV [%]
Max time of exposure [sec]
           
UVA [W/m2]
Percentage of ELV [%]
Max time of exposure [sec]
           
Blu [W/m2]
Percentage of ELV [%]
Max time of exposure [sec]  


SYSTEM TABLES

EN 169 - welding - transmission requirements
current shade number t-313 t-365 tv tA 780-1400
1.2 0.00030 50 90 69
1.4 0.00030 35 65 52
1.7 0.00030 22 50 40
2 0.00030 14 35 28
2.5 0.00030 6.4 24 15
3 0.00030 2.8 13 12
4 0.00030 0.95 6 6.4
5 0.00030 0.3 2.2 3.2
6 0.00030 0.1 0.8 1.7
7 0.00030 0.05 0.3 0.81
8 0.00030 0.03 0.08 0.43
5-20 9 0.00030 0.01 0.04 0.2
20-40 10 0.00030 0.01 0.02 0.1
40-100 11 0.00030 0.00320 0.00600 0.05
100-175 12 0.00030 0.00120 0.00220 0.03
175-250 13 0.00030 0.00044 0.00080 0.01
250-400 14 0.00016 0.00016 0.00030 0.01

15 0.00006 0.00006 0.00011 0.00300

16 0.00002 0.00002 0.00004 0.00300

EN 170 - Shade number of UV absorbing filters
shade number t-313 t-365 tv
2 – 1,2 0.0003 0.3 88
2 – 1,4 0.0003 0.3 65
3 – 1,2 0.0003 50 88
3 – 1,4 0.0003 35 62
3 – 1,7 0.0003 22 50
3 – 2 0.0003 14 35
3 – 2,5 0.0003 6.4 24
3 – 3 0.0003 2.8 13
3 – 4 0.0003 0.95 5.8
3 – 5 0.0003 0.3 2.2

LOADING TIME: 0.007 s.
XS SM MD LG XL

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