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Subchapter 7. General Industry Safety Orders

Group 16. Control of Hazardous Substances

Article 109. Hazardous Substances and Processes

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§5161. Definitions.

Bridging Condition. A condition where grain or other agricultural products are hung up or sticking to the sides of bins, silos, and tanks.
Choked leg. A condition of material buildup in the bucket elevator that results in the stoppage of material flow and bucket movement. A bucket elevator is not considered choked that has the up-leg partially or fully loaded and has the boot and discharge cleared allowing bucket movement.
Closed. As applied to containers, closed means vapor-tight.
Combustible dust. Any finely divided solid material which presents a fire or explosion hazard when dispersed in air.
Combustible liquid. See section 5194(c).
Combustible substance. Any substance which after ignition will continue to burn in air.
Container. Any tank, vat, drum, or other vessel in which a substance is placed for storage, use, processing, or transportation, but the term excludes underground storage tanks, all pipelines and all railroad, highway, water-borne and air-borne transportation vehicles and equipment. An additional definition, for Hazard Communication purposes only, will be found at section 5194(c).
Corrosive. See Appendices A and B to section 5194.
Covered. As applied to containers, covered means providing with a closure which will normally prevent spillage or splashing of contents but is not necessarily liquid or vapor tight; approved safety cans and buggies will be considered covered containers. Equipment listed by the Underwriters' Laboratories or bearing the approval label of other recognized testing laboratories will be acceptable under this definition.
Drum. A portable metal container or barrel, provided with removable plugs or other means by which it can be closed; and having a capacity not less than 15 U.S. gallons or more than 110 U.S. gallons but the term does not include fuel tanks or other equipment on railroad, highway, air-borne or water-borne vehicles.
Flammable. See section 5194(c).
Flat storage structure. A grain storage building or structure, that will not empty completely by gravity, and that has an unrestricted ground level opening for entry, and must be entered to reclaim residual grain using powered equipment or manual means.
Fugitive grain dust. The combustible dust particles emitted from the stock handling system(s) which will pass through a U.S. Standard 40 mesh sieve (425 microns or less).
Grain elevator. A facility engaged in the receipt, handling, storage and shipment of bulk raw agricultural commodities such as corn, wheat, oats, barley, sunflower seeds, and soybeans.
Hazardous substance. A substance, material, or mixture which by reason of being explosive, flammable, poisonous, corrosive, oxidizing, an irritant, or otherwise harmful, is likely to cause injury or illness. Hazardous substance includes a hazardous chemical as defined in section 5194(c) and hazardous waste as defined in section 5192(a)(3). Additional definitions for hazardous substances are found in sections 5194(c), for Hazard Communication purposes only, and 5192(a)(3), for Hazardous Waste Operations purposes only.
Hot work. Any construction, alteration, repair, or demolition involving riveting, welding, burning, or similar fire-producing operations. Grinding, drilling, sand or shot blasting, or similar spark-producing operation shall be considered hot work except when circumstances do not necessitate such classification.
Inside bucket elevator. A bucket elevator that has the boot and more than 20 percent of the total leg height inside the grain elevator structure. Bucket elevators with leg casings that are inside and pass through the roofs of rail or truck dump sheds with the remainder of the leg outside of the grain elevator structure, are not considered inside bucket elevators.
Irritant. See Appendix A to section 5194.
Jogging. Repeated starting and stopping of drive motors in an attempt to clear choked legs.
Laboratory. A plant or generally recognized department or subdivision of a plant where the primary purpose is testing, analysis, inspection, research, experimentation, process development or instruction.
Lagging. A covering on drive pulleys used to increase the coefficient of friction between the pulley and the belt.
Open. As applied to containers, open means not covered or closed.
Oxidizer. A substance other than a blasting agent or explosive as defined in section 5237(a), that initiates or promotes combustion in other materials,thereby causing fire either of itself or through the release of oxygen or other gases. Oxidizers include nitrates, chlorates, perchlorates, peroxides, permanganates, oxygen, and others.
NOTE: Strong oxidizers, especially when finely divided, may initiate combustion in combustible materials. Some substances, not ordinarily considered oxidizers, must be regarded as such under certain circumstances; e.g., finely divided ferric oxide in contact with powdered magnesium or aluminum.
Poison. A substance which when taken in small quantities or low concentrations by mouth, inhaled, or absorbed through the skin rapidly jeopardizes life by other than mechanical or physical action.
Pyrophoric. A substance that will ignite spontaneously in air at a temperature of 130F (54.45C) or below.
Spontaneously flammable substance. See Pyrophoric.
Station. A building, room or section of a room in which a specific operation or part of a process is performed.
Note: Authority cited: Section 142.3, Labor Code. Reference: Section 142.3, Labor Code.
1. Amendment filed 11-18-76; effective thirtieth day thereafter (Register 76, No. 47).
2. Amendment filed 9-14-78; effective thirtieth day thereafter (Register 78, No. 37).
3. Amendment filed 12-10-87; operative 1-9-88 (Register 87, No. 51).
4. Amendment filed 6-5-90; operative 7-5-90 (Register 90, No. 29).
5. Amendment of definition of "Hazardous substance" filed 5-29-2003; operative 6-28-2003 (Register 2003, No. 22).
6. New definition of "Flat storage structure" filed 11-14-2006; operative 12-14-2006 (Register 2006, No. 46).
7. Amendment of definitions of "Corrosive" and "Hazardous substance" filed 5-5-2014; operative 5-6-2014 pursuant to Government Code section 11343.4(b)(3) (Register 2014, No. 19).

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