OSHA Inspection: STROH PRECISION DIE CASTING, LLC

Issued

Aug 19, 2014

Abate by

Sep 17, 2014

Penalty

Initial $4,900 · Current $3,430 Reduced

Hazardous substances E101

General-duty citation text

OSH Act of 1970 Section (5)(a)(1):  The employer did not furnish employment and a place of employment which were free from recognized hazards that were causing or likely to cause death or serious physical harm to employees in that employees were exposed to combustible metal dust (aluminum alloy and steel) deflagration, explosion, and/or other fire hazards while working at or near an indoor fabric filter media-type dust collection system that was not adequately designed and located to prevent or minimize employee exposure in the event of an internal deflagration or other fire event:  On or about April 4th, 2014,  the indoor Torit filter media-type dust collection system (collector and ducting) servicing the tumble blast and hanger blast lines generating steel shot abrasive blasting dust and horizontal belt sanders/grinding wheel generating aluminum alloy dust presented the following recognized hazards:  a) The Torit dust collector was located indoors without a means of explosion protection.  b) The Torit dust collector was located indoors without a means of fire protection.  c) The Torit dust collector system did not incorporate a means of deflagration propagation protection (isolation) for the upstream processes/work stations.  d) The dust collection duct lengths were not as short as possible and contained irregularities such as 90 degree duct transitions.  e) The dust collection system was not designed to maintain a minimum duct transport velocity of at least 4,500 feet per minute to prevent settling and accumulation of dust in the ducting.  f) The dust collection system collected potentially incompatible dusts (iron oxide from abrasive steel blasting media operations and aluminum alloy from grinding and sanding operations).  Among other methods, feasible methods to correct this hazard would be to comply with the National Fire Protection Association?s (NFPA) Standards NFPA 484 ?Standard for Combustible Metals, 2012 ed.)? - Sections 8.1.4.3.1, 8.7.3.3 (14.8.3.19.4), 8.7.3.5, 8.7.3.6, 8.7.3.6.2, 8.7.3.13.1 (14.8.3.13.1, 14.8.3.22.1, 14.8.3.22.7), 8.7.3.17 (14.8.3.17, 14.8.3.24), 8.7.3.19.1, 8.7.3.19.2 (14.8.3.19.2), 14.8.3.22.5.  Similar guidance is contained in the Aluminum Association?s publication F-1: ?Guidelines for Handling Aluminum Fines Generated During Various Aluminum Fabricating Operations?.  Specifically, (1) relocate dry dust collectors outside and provide them with a recognized method of explosion protection such as deflagration venting to a safe location in accordance with NFPA 68 ?Standard on Explosion Protection by Deflagration Venting? or equip indoor dust collectors with a recognized method of explosion protection such as deflagration venting to a safe outdoor location in accordance with NFPA 68 or chemical deflagration suppression in accordance with NFPA 69 ?Standard on Explosion Prevention Systems?; (2) isolate dust collectors from the upstream process and the unit?s discharge collection drums via the use of an active or passive deflagration isolation system in accordance with NFPA 69; (3) prohibit the recycling of dust collector exhaust into indoor locations; (4) where deflagration venting is utilized, develop and maintain data sheets, installation details, and design calculations for each vent closure application that verifies the vent area is sufficient to prevent deflagration pressure from exceeding the enclosure strength and identifies areas exposed to potential over-pressure, event propagation, and fireball effects during venting; (5) provide dust collectors with a listed method of fire detection and suppression appropriate for the metals being captured in accordance with NFPA 484; (6) ensure lengths of ducting to collectors are as short as possible and do not contain any unnecessary bends; (7) provided separate dedicated collection systems for the collection of aluminum alloy and abrasive blasting media steel shot dusts; (8) design for and routinely ensure that dust collection systems are providing at least 4,500 feet per minute of air velocity in all branches of the system; (9) where duct transitions are used, ensure that branches enter at a gradual expansion of approximately 30 degrees and avoid 90 degree transitions.  Wet collectors may be used as an alternative to dry-type collectors provided that the applicable guidance for design, installation, and maintenance within NFPA 484 is followed.