In this paper we describe the permissible time of arc sound exposure from standpoint of conservation of hearing acuity.
The permissible time of arc sound exposure was revealed in accordance with the standard of ACGIH (American Conference of Governmental Industrial Hygienists) in various welding methods and conditions.
The particular attention should be paid to high current arc welding, pulsed arc welding, plasma jet or the like: in this case, ear plug and ear muffler have the effects of conservation of hearing acuity.
The standard of ACGIH is different from that of JCGIH (Japan Conference of Governmental Industrial Hygienists) in terms of the permissible arc sound exposure. It is shorter in JCGIH than in AC-GIH in most cases.
