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It has been documented that some dusts generated while processing agricultural products, such as grain and sugar, can constitute combustible dust hazards. After a catastrophic dust explosion in a sugar refinery in 2008, the Occupational Safety and Health Administration (OSHA) initiated action to develop a mandatory standard to comprehensively address the fire and explosion hazards of combustible dusts. Cotton fiber and related materials from cotton ginning, in loose form, can support smoldering combustion if ignited by an outside source. However, dust fires and other more hazardous events, such as dust explosions, are unknown in the cotton ginning industry. Dust material that accumulates inside cotton gins and almond huller plants during normal processing was collected for testing to determine combustibility. Cotton gin dust is composed of greater than 50% inert inorganic mineral dust (ash content), while almond huller dust is composed of at least 7% inert inorganic material. Inorganic mineral dust is not a combustible dust. The collected samples of cotton gin dust and almond huller dust were sieved to a known particle size range for testing to determine combustibility potential. Combustibility testing was conducted on the cotton gin dust and almond huller dust samples using the UN test for combustibility suggested in NFPA 652.. This testing indicated that neither the cotton gin dust nor the almond huller dust should be considered combustible dusts (i.e., not a Division 4.1 flammable hazard per 49 CFR 173.124).

Since its formation in 1971, the Occupational Safety and Health Administration (OSHA) has recognized agriculture was not covered by their noise standards. However, in 2014, OSHA cited two gin companies under the OSHA general duty clause for an alleged failing to protect employees from exposure to hazardous noise levels by not requiring employees to wear hearing protection. In January 2016, OSHA withdrew both citations. The 2014 interpretations by OSHA were contrary to OSHA’s enforcement of the federal OSHA noise standards and guidance since 1971 when OSHA came into existence; 1981, when the hearing conservation amendment was promulgated and agriculture was specifically excluded; and 1983 when the OSHA 90 dBA level was reaffirmed. OSHA’s contention that their general duty clause requires these two gins to mandate hearing protection conflicts with OSHA guidance specifically related to this topic, as well as over 40 years of consistent enforcement of the Occupational Noise Exposure ("noise standard") standards relating to agriculture. OSHA has not presented any new health data indicating that working in a cotton gin over a working lifetime causes occupational noise-induced hearing loss, or issued any new guidance on enforcement of the OSHA noise standard as it applies to agriculture. The science and OSHA’s current guidance continue to support the conclusion that intermittent/interrupted exposure to noise in agriculture, including cotton gins, is not an occupational hazard, requiring mandatory hearing protection and a hearing conservation program. The OSHA noise regulations as they apply to agriculture, including cotton gins, are discussed.

Mattresses/bedding and upholstered furniture are subject to ignition by cigarettes (smoulder) and open flames leading to injuries, fatalities and property damage. There are mandatory and voluntary cigarette ignition standards in the USA for mattresses (16 CFR 1632) and upholstered furniture (UFAC voluntary standards) as well as open flame ignition standards in California (TB 117) and the UK (BS 5852). Open flame ignition standards are being considered/developed for these products. Some suggest that fire retardant (FR) treatments to prevent/reduce open flame ignitions also reduce cigarette ignitions. Some reports suggest that the smoulder ignition propensity of some cellulosic fabrics can be affected adversely by open flame ignition resistance treatments. Ignitions caused by cigarettes and open flames result from different types of combustion that are retarded by different mechanisms. Flaming combustion is a gas phase reaction and occurs when heat causes degradation of the polymer releasing volatile products that undergo rapid oxidation in the air, whereas smouldering combustion is a direct oxidation of either the polymer or its char. The results of textile/fibre industry studies with FR treated upholstery fabrics and a critical review of the available published literature indicate that cigarette ignition propensity of cellulose fabrics is complicated and affected by many factors and that smoulder ignition resistance of these fabrics can be affected adversely by open flame ignition resistance treatments. Copyright © 2004 John Wiley & Sons, Ltd.

Bales of cotton were classified by the International Maritime Organization (IMO) code regulations as a flammable solid (Class 4.1), which required hazardous goods papers to accompany waterborne shipments. Various scientific investigations were conducted to evaluate the flammability hazard of bales of cotton to determine if this hazardous designation was valid. Cigarette (NFPA 261/ ASTM E1352), match (NFPA 705) and open flame (CA TB 129) tests were conducted; the potential for self-heating and spontaneous combustion was evaluated; and the potential of cotton bales sustaining smouldering combustion in their interiors at various compression densities was studied. These studies showed that bales of cotton should not be required to have the hazardous designation, 'flammable solid', and led to the IMO and the US Department of Transportation (DOT) removing the designation for baled cotton [compressed to a density of 360 kg/m(3) (22.4 lb/ft(3)) or greater; meets ISO 8115], with effect from I January 1999. Language: en

The interaction of water with cellulose and its influence on the nuclear spin dynamics in Gossypium barbadense (Pima) cotton were investigated by 1H and 13C solid-state NMR techniques. 1H spin diffusion results from a Goldman-Shen experiment indicate that the water is multilayered. 1H MAS experiments provide evidence of a range of correlation times for the water, indicative of molecular motion ranging from restricted to relatively mobile. The 1H spin-lattice relaxation time varies with water content and is different for static and MAS conditions. By coupling the Goldman-Shen sequence with 13C CP/MAS, cross-polarization from the molecularly mobile water protons distributes magnetization throughout the cellulose (as opposed to enhancing 13C resonances from only the crystalline or the amorphous domains or from only the surface of the cellulose). However, spatial localization of the combined Goldman-Shen-13C CP/MAS experiment using both short mixing and contact times yields a spectrum consistent with predominantly the Iβ polymorph of cellulose. Longer mixing times and the same, short contact time yield a spectrum that is indicative of an increased Iα polymorph content in the crystallite interiors relative to the smaller values found with short mixing times.