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

## "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

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