Evaluation and Monitoring of Uvr in Shield Metal Arc Welding Processing

Abstract

This study established a comprehensive approach to monitoring UVR magnitude from Shield Metal Arc Welding (SMAW) processing and quantified the effective exposure based on measured data. The irradiances from welding UVR were calculated with biological effective parameter (Slambda) for human exposure assessment. The spectral weighting function for UVR measurement and evaluation followed the American Conference of Governmental Industrial Hygienists (ACGIH) guidelines. Arc welding processing scatters bright light with UVR emission over the full UV spectrum (UVA, UVB, and UVC). The worst case of effective irradiance from a 50 cm distance arc spot with a 200 A electric current and an electrode E6011 (4 mm) is 311.0 microW cm(-2) and has the maximum allowance time (Tmax) of 9.6 s. Distance is an important factor affecting the irradiance intensity. The worst case of the effective irradiance values from arc welding at 100, 200, and 300 cm distances are 76.2, 16.6, and 12.1 microW cm(-2) with Tmax of 39.4, 180.7, and 247.9 s, respectively. Protective materials (glove and mask) were demonstrated to protect workers from hazardous UVR exposure. From this study, the methodology of UVR monitoring in SMAW processing was developed and established. It is recommended that welders should be fitted with appropriate protective materials for protection from UVR emission hazards.

Efficacy and safety assessment of a novel ultraviolet C device for treating corneal bacterial infections

“…Indeed, arc‐eye, or welders flash from unprotected exposure of the eye to arc welding, caused by an almost equal mixture of UVA, B and C, 16 usually heals without long‐term sequelae. The limit for daily exposure to UV from arc welding, based on corneal exposure at 50 cm from a welding arc has been measured at 0.311 mW/cm 2 , equating to a dose of 3 mJ/cm 2 over 9.6 s 17 . Within this context, it would appear that a short duration, low dose of UVC, such as that delivered in this study, should be relatively safe.…”

Personal Exposure to Metal Fume, NO2, and O3 among Production Welders and Non-welders

“…Ozone is produced during the welding arc process and causes free radical generation in the lungs 27) . At low concentrations, ozone acts as a pulmonary irritant and can cause shortness of breath, wheezing, and tightness in the chest, and more severe exposures can cause pulmonary edema 28) .…”

Ignition of Welding Arc and UV Actinic Hazard Evaluation

“…A welding arc is one of the strongest technological sources of artificial optical radiation, especially in the ultraviolet and visible range [5][6][7][8][9][10][11][12][13][14][15]. It creates a wide range of risks for the skin and eyes of both welders and workers or people around the welding workstation [13,14,[16][17][18][19][20][21]. Strong UV radiation is emitted by the welding arc into the surrounding environment, and a great number of workers at the workplaces, where welding is performed, are exposed to ultraviolet radiation (UVR).…”

“…Many studies were carried out to measure optical radiation from the welding arc for the purpose of hazard evaluation, and they proved the strong influence of welding parameters on UV radiation emission [8,10,14,31]. The relative spectrum of arc emission depends mainly on the chemical composition of the welded material, but the absolute intensity of the radiation depends on the wire/electrode diameter, the chemical composition of material from which the electrode is made, current intensity, and arc voltage [5,8,10,13]. For example, the study of Nakashima et al proved that the UV emission is more hazardous when the welding materials include magnesium and when the electrodes contain oxides [14].…”

“…A few studies on optical hazard evaluation from arc welding report a high increase of optical radiation emission during arc ignition [8][9][10]12,14,15], but all of them relate to the results of Eriksen's study [7]. Other studies related to UVR exposure assessment exclude arc ignition emission; measurements (or analysis) were started after the arc ignition [8][9][10]13,14]. Depending on the study and measuring equipment (polysulfone film, radiometer, CCD spectroradiometer), a single (or continuous) measurement duration of arc radiation (after arc ignition) was from 5 s-50 s, for example: 6 s [9], 50 s [12], 10 s [5], 5 s [14], and 15 s [13].…”