Respirator sufficient

Uujsterrf gas (YcUotv Cross), in July, 1917. Mustard gas is 36 limes as )H>t.sonous stu chlorine. The Small Box Respirator sufficiently protectfxf (he ej es and nose agaiast mustard gas. The mustard gas... 

Glass fibers <3 fim are to be avoided because these are classed as respirable fibers which can enter and damage lung passages. Most glass fiber products have sufficient fiber lengths to prevent lung entry even if their diameters are <3 fim. 

Health and Safety Factors and Regulations. Iodine is much safer to handle at ordinary temperatures than the other halogens because iodine is a soHd and its vapor pressure is only 1 kPa (7.5 mm Hg) at 25°C, compared to 28.7 kPa (215 mm Hg) for bromine and 700 kPa (6.91 atm) for chlorine. When handling properly packed containers, usual work clothes are sufficient. In the handling of soHd, unpacked iodine, mbber gloves, mbber apron, and safety goggles are recommended. Respirators or masks are also recommended. 

Vapor Toxicity. Laboratory exposure data indicate that vapor inhalation of alkan olamines presents low hazards at ordinary temperatures (generally, alkan olamines have low vapor pressures). Heated material may cause generation of sufficient vapors to cause adverse effects, including eye and nose irritation. If inhalation exposure is likely, approved respirators are suggested. Monoethan olamine and diethanolamine have OSHA TLVs of 3 ppm. 

Thorium is potentially hazardous. Einely divided thorium metal and hydrides can be explosive or inflammatory hazards with respect to oxygen and halogens. Einely divided Th02 and other inorganic salts also present an inhalation and irritation hazard. The use of standard precautions, skin covering, and a conventional dust respirator should be sufficient for handling thorium materials. 

Overbreath in using a respirator, when the wearer s breathing rate exceeds the ability of the respirator to provide a volume of air sufficient to ensure that a positive pressure is maintained inside the face piece. 

Barbiturates such as amobarbital inhibit NAD-hnked dehydrogenases by blocking the transfer from FeS to Q. At sufficient dosage, they are fatal in vivo. Antin cin A and dimercaprol inhibit the respiratory chain between cytochrome b and cytochrome c. The classic poisons H2S, carbon monoxide, and cyanide inhibit cytochrome oxidase and can therefore totally arrest respiration. Malonate is a competitive inhibitor of succinate dehydrogenase. 

The antagonistic effects of sodium pentothal on the blood pressure and the respiratory effects of chlordan are illustrated in Figure 1, C. The intermittent severe tremors with concomitant Cheyne-Stokes type of respiration produced by the injection of chlordan were decreased or entirely abolished, and both the respiratory rate and depth were restored to near normal. A dose of barbiturate sufficient to diminish the tremors appreciably and to restore the respiration to normal also produced a temporary drop of 10 to. 40 mm. of mercury in blood pressure. 

Goggles, impervious gloves, protective clothes and shoes are recommended. Chemical cartridge respirators are sufficient for routine handling. Air-line respirators or self-contained breathing apparatus are recommended for high concentrations. 

If Ss is not present in sufficient concentration, Xbw is used for endogenous respiration. 

On pp. 2 and 43 reference was made to the intense myosis that we experienced when exposed to low concentrations of D.F.P. In fact, appreciable myosis is brought about by concentrations very much lower than that mentioned on p. 2. The author has frequently noted that, after dealing with D.F.P. and related compounds even under carefully controlled laboratory conditions (e.g. using fume cupboards, respirators, etc.), minute traces of material have adhered to clothing and some hours later gradually vaporized and were sufficient to cause myosis with its... 

Negligible sensory irritation was caused by di-isopropyl phosphorofluoridate at a concentration of 1 part in 10. This, coupled with the fact that the odour was practically undetectable, means that sufficient warning is not usually given at this concentration to suggest the use of respirators. Exposures at this concentration cause severe myosis which persists for several days and causes considerable incapacitation (Report no. 12 by McCombie and Saunders to Ministry of Supply, 4 August 1943). 

When in later years Krebs reviewed the major points which had to be established if the cycle was to be shown to be operative in cells, the obvious needs were to find the presence of the required enzymes and to detect their substrates. As the substrates are present in the cycle in catalytic amounts their accumulation required the use of inhibitors. Krebs also stressed that rates of oxidation of the individual substrates must be at least as fast as the established rates of oxygen uptake in vivo, an argument first used by Slator (1907) with reference to fermentation A postulated intermediate must be fermented at least as rapidly as glucose is. (See Holmes, 1991). This requirement did not always appear to be met. In the early 1950s there were reports that acetate was oxidized by fresh yeast appreciably more slowly than the overall rate of yeast respiration. It was soon observed that if acetone-dried or freeze-dried yeasts were used in place of fresh yeast, rates of acetate oxidation were increased more than enough to meet the criterion. Acetate could not penetrate fresh yeast cell walls sufficiently rapidly to maintain maximum rates of respiration. If the cell walls were disrupted by drying this limitation was overcome, i.e. if rates of reaction are to be... 

Certain organic forms of mercury can elicit specific damage in the main cell body of peripheral neurons. Similar responses are associated with certain natural products called vincristine and vinblastine, both of which have been used as antileukemic medicines. The deadly botulinum toxins, mentioned earlier in this chapter, block transmission of nerve impulses at the synapses of motor neurons. This blockage results in muscular paralysis which, if sufficiently severe, can lead to death, usually because respiration is impaired. The once widely used pesticide, DDT, is an organic chemical that also acts on the nervous system at this site, although it can also mount an attack on areas of the CNS. 

Sufficient evidence has proven that VC can cause cancer of the liver after prolonged exposure to only minute quantities (parts per inillion). Elaborate hardware precautions are taken to eliminate escape of any VC to the atmosphere. Personnel involved in production or use of VC often wear respirators whenever there is a possibility of a leak. 

---