Hydrogen, safety aspects

Health nd Safety Factors. Thionyl chloride is a reactive acid chloride which can cause severe bums to the skin and eyes and acute respiratory tract injury upon vapor inhalation. The hydrolysis products, ie, hydrogen chloride and sulfur dioxide, are beheved to be the primary irritants. Depending on the extent of inhalation exposure, symptoms can range from coughing to pulmonary edema (182). The LC q (rat, inhalation) is 500 ppm (1 h), the DOT label is Corrosive, Poison, and the OSHA PEL is 1 ppm (183). The safety aspects of lithium batteries (qv) containing thionyl chloride have been reviewed (184,185). 

A survey, with many references, of 14 classes of preparative reactions involving hydrogen peroxide or its derivatives emphasises safety aspects of the various procedures [11]. Following the decomposition of 100 1 of 50% aqueous hydrogen peroxide which damaged the 630 1 stainless vessel rated at 6 bar, the effect of added contaminants and variations in temperature and pH on the adiabatic decomposition was studied in a 1 1 pressure vessel, where a final temperature of 310°C and a pressure around 200 bar were attained. Rust had little effect, but addition of a little ammonia (pH increased from 1.8 to 6.0) caused the induction period to fall dramatically, effectively from infinity to a few h at 40°C and a few min at 80°C. Addition of sodium hydroxide to pH 7.5 reduced the induction period at 24°C from infinity to about 4 min [12],... 

Safety aspects of hydrogen are covered in more detail in Chapter 16. 

Safety aspects of drum storage, pellet screening, dust removal, reactor loading and unloading, and activation of process catalysts are discussed [1], and reprocessing aspects are considered, with disposal as a last resort [2], Hydrogenation catalysts introduce their own problems [3],... 

Possible hazards introduced by variations in experimental techniques in Kjeldahl nitrogen determination were discussed [1]. Modem variations involving use of improved catalysts and hydrogen peroxide to increase reaction rates, and of automated methods, have considerably improved safety aspects [2], An anecdote is given of the classic technique when sodium hydroxide was to be added to the sulphuric acid digestion and was allowed to trickle down the wall of the flask. It layered over the sulphuric acid. Gentle mixing then provoked rapid reaction and a steam explosion [3],... 

The safety aspects of fuels involve their toxicity on the one hand and the fire hazard properties on the other. In addition to the toxicity of their combustion products, the fuels themselves can be toxic. The toxicity increases as the carbon to hydrogen ratio increases. Hydrogen and its main combustion product, water or water vapor, are not toxic. However, NOx, which can be produced through the flame combustion of hydrogen (as well as through the combustion of fossil fuels) displays toxic effects. 

Hydrogen is certainly a clean and abundant energy but in the same time its large-scale use still suffers from a psychological handicap linked to safety aspects given some of its properties,16 17 18 particularly its inflammability and the high risk of detonation (subsonic or supersonic). This is clearly indicated in Table 5 where some of the properties are compared with another industrial gas, the propane. 

Session 6 Safety aspects of nuclear hydrogen production Co-chairs Jozef Misak (UJV), Theodore Krause (ANL)... 

A panel of experts representing nuclear regulatory agencies (US NRC), government national laboratories and agencies (DOE/ANL and JAEA) and universities [Purdue University (USA), National Autonomous University of Mexico, and Kyushu University (Japan)] was convened to present advances in understanding the safety aspects of nuclear hydrogen production. 

SESSION VI SAFETY ASPECTS OF NUCLEAR HYDROGEN PRODUCTION... 

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