Explosion hazards hydrogen

UNUSUAL FIRE AND EXPLOSION HAZARDS Hydrogen may be present... 

UNUSUAL FIRE AND EXPLOSION HAZARDS Hydrogen produced by the corrosive vapors reacting with metals, concrete, etc., may be present. 

Precaution Flamm. exposed to heat or flame severe explosion hazard exposed to heat or flame incompat. with oxidizing agents (increases fire/explosion hazard), hydrogen trisulfide (explosive reaction possible) Hazardous Decomp. Prods. Heated to decomp., emits acrid smoke and irritating fumes NFPA Health 0, Flammability 2, Reactivity 0 Storage Store in cool, dry, well-ventilated area out of direct sunlight... 

Iron dust does present a moderate fire and explosion hazard when exposed to heat and flame. Although normally not very reactive, under certain circumstances iron can react with water to Hberate flammable hydrogen gas. 

Calcium metal and most calcium compounds are nontoxic. In massive pieces the metal does not spontaneously bum in air. Calcium can be touched with dry bare hands without harm. Care must be taken, however, to avoid contact with water owing to the exothermic Hberation of hydrogen and the resulting explosion hazard. Calcium must always be kept dry and preferably sealed in the shipping containers. 

Explosion Hazards. The electrolysis of aqueous solutions often lead to the formation of gaseous products at both the anode and cathode. Examples are hydrogen and chlorine from electrolysis of NaCl solutions and hydrogen and oxygen from electrolysis of water. The electrode reactions. 

Eire and explosion hazards associated with the storage and handling of hydrogen peroxide... 

Vapor Density (VD) — the mass per unit volume of a given vapor/gas relative to that of air. Thus, acetaldehyde with a vapor density of 1.5 is heavier than air and will accumulate in low spots, while acetylene with a vapor density of 0.9 is lighter than air and will rise and disperse. Heavy vapors present a particular hazard because of the way they accumulate if toxic they may poison workers if nontoxic they may displace air and cause suffocation by oxygen deficiency if flammable, once presented with an ignition source, they represent a fire or explosion hazard. Gases heavier than air include carbon dioxide, chlorine, hydrogen sulfide, and sulfur dioxide. 

Numerous types of batteries are available. A comparison of batteries by cell type is shown in Table 17-1. Rechargeable batteries emit hydrogen to the atmosphere, and hence must be installed such that hydrogen does not accumulate to create an explosion hazard. Ventilation should be provided for battery compartments. 

This study investigated risks to the public from serious accidents which could occur at the industrial facilities in this part of Essex, U.K. Results are expressed as risk to an individual and societal risk from both existing and proposed installations. Risk indices were also determined for modified versions of the facilities to quantify the risk reduction from recommendations in the report. Nine industrial plants were analyzed along with hazardous material transport by water, road, rail and pipeline. The potential toxic, fire and explosion hazards were assessed for flammable liquids, ammonia, LPG, LNG, and hydrogen fluoride (HE). The 24 appendices to the report cover various aspects of the risk analysis. These include causes and effects of unconfined... 

Type and specifications on fan driver, gear types, pow er voltage, phase, cycles. Motors should at least meet specifications equivalent to totally enclosed, fan cooled, or if in explosive hazardous area, TEFC Class I, Group D (except this not acceptable in hydrogen or acetylene atmosphere). Due to moisture conditions around this equipment, it should be protected against moisture penetration and corrosion. 

Reaction (2) is often preferred because of the hazard of unconsumed chlorine from Reaction (1) reacting explosively with hydrogen commonly used as a reducing agent. 

We now illustrate the opposite case where the intermediate is in fact a highly undesirable substance, as it presents a health, or even explosion, hazard. The hydrogenation of aromatic nitro compounds, such as the one shown in Fig. 2.6, is industrially important for the production of dyes, whiteners, agrochemicals and pharmaceuticals. The reaction occurs in the presence of a platinum catalyst and proceeds via intermediates, among which the hydroxylamine (-NHOH) species is particularly hazardous, as it is both carcinogenic and explosive. Unfortunately, standard platinum catalysts give rise to high levels of this undesired intermediate. 

The only disadvantage to the use of hydrogen as a carrier gas Is the real or perceived explosion hazard from leaks within the column oven. Experience has shoim that the conditions required for a catastrophic explosion may never be achieved in practice.. However, commercially available gas sensors will automatically switch off the column oven and carrier gas flow at air-hydrogen mixtures well below the explosion threshold limit [143]. 

Storage stability Store DF in lead and wax-lined carboys, high-density polyethylene bottles, or nickel-lined containers in well-ventilated areas. Never store DF with alcohols DF will react with alcohols to form lethal chemicals, such as crude GB. Incompatible with water, glass, concrete, most metals, natural rubber, leather, and organic materials like glycols. The acidic corrosive hydrolysis products may react with metals, such as Al, Pb, and Fe, to give off hydrogen gas, a potential fire and explosive hazard. 

There is an explosion hazard dining the palladium-catalysed hydrogenation of the... 

Temperature control during pressure hydrogenation of cis- or tram-isomers is essential, since at 155°C violent decomposition to carbon, hydrogen and carbon monoxide with development of over 1 kbar pressure will occur. The material should not be heated above 100°C, particularly if acid or base is present, to avoid exothermic polymerisation [1], The m-isomer is readily cyclised to 2,3-dimethylfuran, which promotes lire and explosion hazards. These were measured for the cis- and tram-isomers, and for fram-3-methyl-l-penten-4-yn-3-ol [2],... 

The flammability and explosive hazard of ferrosilicon powder is increased substantially during grinding in a vibratory mill [1], Explosion hazards from air-hydrogen,—acetylene, or—propane mixtures formed during preparation of ferrosilicon containing alkaline earth additives are attributed to contact of barium or magnesium carbide or silicide additive with atmospheric moisture [2],... 

Fire and Explosion Hazards associated with Storage and Handling of Hydrogen Peroxide, Merrilield, R., Specialist Inspectors Report No. 19, Bootle, HSE. 1988... 

UNUSUAL FIRE EXPLOSION HAZARDS Fires involving this chemical may result in the formation of hydrogen cyanide. 

In any case, covering may be impracticable for other reasons. Many processes as they are currently designed depend upon at least visual access by operators for process control, and in other instances the production of odorous chemicals such as hydrogen sulphide can be accompanied by the formation of methane, giving a potential fire or explosion hazard. 

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