Section 325.62109. Inert-gas metal-arc welding.

(1) Since the inert-gas metal-arc welding process involves the production of ultra-violet radiation of intensities of 5 to 30 times that produced during shielded metal-arc welding, the decomposition of chlorinated solvents by ultra-violet rays, and the liberation of toxic fumes and gases, employees shall not be permitted to engage in, or be exposed to, the process until the following special precautions have been taken:

(a)   The use of chlorinated solvents shall be kept at least 200 feet, unless shielded, from the exposed arc, and surfaces prepared with chlorinated solvents shall be thoroughly dry before welding is permitted on such surfaces.

(b)     Welders and other employees who are exposed to radiation shall be suitably protected so that the skin is covered completely to prevent burns and other damage by ultra- violet rays. Welding helmets and hand shields shall be free of leaks and openings, and free of highly reflective surfaces.

(c)     When inert-gas metal-arc welding is being performed on stainless steel, the requirements of R 325.62108(2) shall be met to protect against dangerous concentrations of nitrogen dioxide.

(2)   Employees in the area not protected from the arc by screening shall be protected by filter lenses meeting the requirements of Construction Safety Standard Part 6 ‘Personal Protective Equipment’ as referenced in R 325.62102.

(3)    When 2 or more welders are exposed to each other's arc, filter lens goggles of a suitable type, meeting the requirements of Construction Safety Standard Part 6 ‘Personal Protective Equipment’ as referenced in R 325.62102, shall be worn under welding helmets.

(4)   The welder shall use hand shields to protect against flashes and radiant energy when either the helmet is lifted or the shield is removed.

History: 2014 AACS.