System effect

Mild exposure to HF via inhalation can irritate the nose, throat, and respiratory system. The onset of symptoms may be delayed for several hours. Severe exposure via inhalation can cause nose and throat bums, lung inflammation, and pulmonary edema, and can also result in other systemic effects including hypocalcemia (depletion of body calcium levels), which if not promptly treated can be fatal. Permissible air concentrations are (42) OSHA PEL, 3 ppm (2.0 mg/m ) as E OSHA STEL, 6 ppm (5.2 mg/m ) as E and ACGIH TLV, 3 ppm (2.6 mg/m ) as E. Ingestion can cause severe mouth, throat, and stomach bums, and maybe fatal. Hypocalcemia is possible even if exposure consists of small amounts or dilute solutions of HE. 

Both Hquid HE and the vapor can cause severe skin bums which may not be immediately painful or visible. HE can penetrate skin and attack underlying tissues, and large (over 160 cm ) bums may cause hypocalcemia and other systemic effects which may be fatal. Even very dilute solutions may cause bums. Both Hquid and vapor can cause irritation to the eyes, corneal bums, and conjunctivitis. 

Dihydroxybenzenes (DHBs) are slightly more acutely toxic than phenol (Table 5). Contact with dihydroxybenzene through oral, dermal, or respiratory routes can induce significant systemic exposure. Skin or eye effects have been demonstrated during chronic or accidental professional exposure. No systemic effect has been described in such circumstances. 

Because of the interrelationship of the system measures, rehabihty should not be considered by itself since, if taken alone, it does not express the totahty of attributes that contribute to system effectiveness. However, in practice, rehabihty has gained the most acceptance and uniformity of definition. The other concepts described are not always defined uniformly from group to group and are sometimes used interchangeably. Further discussion of these concepts is found in References 1 and 2. 

System Effectiveness. A system is designed to perform some intended function in a prescribed fashion. This overall capabihty is termed system effectiveness. Figure 2 illustrates the design trade-offs that constitute the components of system effectiveness. 

From the standpoint of a military product, system effectiveness is the probabiUty that the system meets successfully an operational demand within a given time when operating under specified conditions. From the standpoint of commercial products, system effectiveness is harder to define, but basically means customer satisfaction. There are several system parameters that are important to the customer. Some of these parameters are defined below. 

Toxicology. The nitroparaffins have minimal effects by way of actual contact. There were neither systemic effects nor irritation in dermal studies in rabbits. Human exposure of a prolonged or often-repeated nature has led to low grade irritation attributable to removal of oil from the skin, an effect produced by most organic solvents. Eye irritation potential of all four nitroparaffins has been deterrnined in rabbits. Other than a transient slight redness and some lachrymation, no effects were noted. The average Draize score was 0.0. The acute oral toxicity, LD q, of all four nitroparaffins has been deterrnined in the rat (Table 8). 

The decomposition kinetics of an organic peroxide, as judged by 10-h HLT, largely determines the suitabiUty of a particular peroxide initiator in an end use appHcation (22). Other important factors ate melting point, solubiUty, cost, safety, efficiency, necessity for refrigerated storage and shipment, compatibihty with production systems, effects on the finished product, and potential for activation. 

The inorganic tin compound that has received the most study from a toxicological viewpoint is stannic oxide. Autopsies performed on workers in the tin mining and refining industry, who inhaled tin oxide dust for as long as 20 yr, disclosed no pulmonary fibrosis (57). Inhalation for long periods produces a benign, symptomless pneumoconiosis with no toxic systemic effects (58). 

In addition to the effect of biological variabihty in group response for a given exposure dose, the magnitude of the dose for any given individual also determines the severity of the toxic injury. In general, the considerations for dose—response relationship with respect to both the proportion of a population responding and the severity of the response are similar for local and systemic effects. However, if metabohc activation is a factor in toxicity, then a saturation level may be reached. 

The threshold limit value—time integrated average, TLV—TWA, of chlorine dioxide is 0.1 ppm, and the threshold limit value—short-term exposure limit, STEL, is 0.3 ppm or 0.9 mg /m of air concentration (87,88). Chlorine dioxide is a severe respiratory and eye irritant. Symptoms of exposure by inhalation include eye and throat irritation, headache, nausea, nasal discharge, coughing, wheezing, bronchitis, and delayed onset of pulmonary edema. Delayed deaths occurred in animals after exposure to 150—200 ppm for less than one hour. Rats repeatedly exposed to 10 ppm died after 10 to 13 days of exposure. Exposure of a worker to 19 ppm for an unspecified time was fatal. The ingested systemic effects of low concentration chlorine dioxide solutions are similar to that of chlorite. 

Ingestion of small amounts of tetrachloroethylene is not likely to cause permanent injury however, ingestion of large amounts may result in serious injury or even death. AH containers should be properly labeled. If solvent is swaHowed, consult a physician immediately. Do not induce vomiting. If solvent is aspirated it is rapidly absorbed through the lungs and may cause systemic effects and chemical pneumonia. 

Lowest observed effect level (PbB) (Mg/dl) Heme synthesis and hematological effects Neurological effects Renal system effects Gastrointestinal effects ... 

An exposure to a specific chemical in relatively low concentrations over a period may result in chronic effects. At higher concentrations, the effects may be acute. Some chemicals produce local damage at their point of contact with, or entry into, the body others produce systemic effects, i.e. they are transported within the body to various organs before exerting an adverse effect. 

Health Elazards - Personal Protective Equipment Self-contained breathing apparatus protective clothing if exposed to liquid. Symptoms Following Etqjosure If concentration of gas in hi enough, may cause asphyxiation. No detectable systemic effects, even at 5 % concentration in air. Treatment for Exposure Remove victim to open air. If the is overcome by gas, qjply artificial resuscitation. Toxicity by Inhalation (Threshold Limit Value) Data not available Short-Term Inhalation Limits Data not available Toxicity by Ingestion Not pertinent Late Toxicity None Vapor (Gas) Irritant Characteristics Vapors are nonirritating to the eyes and throat. Liquid or Solid Irritant Characteristics No appreciable hazard. Practically harmless to the skin because it is very volatile and evaporates quickly. May cause some frostbite. Odor Threshold Data not available. 

Health Hazards Information - Recommended Personal Protective Equipment Full protective clothing gas mask or self-contained breathing apparatus Symptoms Following Exposure Inhalation causes irritation of respiratory system, pulmonary edema, and systemic effects. Vsqrar irritates eyes. Liquid causes severe burns of eyes and severe irritation or burns of mouth and stomach General Treatment... 

Endrin 0.002 0.002 Nervous system effects Residue of banned insecticide... 

Oxamyl (Vydate) 0.2 0.2 Slight nervous system effects Runoff/leaching from insecticide used on apples, potatoes, and tomatoes... 

The next level of presentation is a technical summary that gives details of the risks including the system s importance measures systems, effects of data changes, and assumptions that are critical to the conclusions. It details the conduct of the analysis - especially the treatment of controversial points. The last level of presentation includes all of the details including a roadmap to the analysis so a peer can trace the calculations and repeat them for verification. 

In case use of local protection system effect on exposure of the process, load calculations shall he revised. products... 

TCDD is the most potent inducer of chloracne. This has been well known since the accident in Seveso, Italy, in 1976 in which large amounts of TCDD were distributed in the environment subsequent to an explosion in a factory that produced a chlorophenoxy herbicide, 2,4,5-T. TCDD is an impurity produced during the production of 2,4,5-T. The most common long-term effect of TCDD exposure was chloracne. Exposed individuals also suffered increased excretion of porphyrins, hyper-pigmentation, central nervous system effects, and liver damage and increased risk of cancer was a long-term consequence of the exposure. In addition to TCDD, polychlorinated biphenyls (PCBs), polychlorinated dibenzofurans, and polychloronaphthalens cause chloracne as well as other effects typical of TCDD. 7i... 

Gnmitlyn, M. I., and A. M. Zhivov. 1983. Improvement of air-conditioning systems effectiveness in the operation halls of the automatic telephone exchange stations. In Proceedings of the Conference Improvements in the Ventilation and Air-Conditioning Systems Effectiveness. LDNTR, lamingrad. 

Li Z., L. L. Christianson, J, S. Zhang, and A. Zhivov. 1994. Cold air jets systems effects on the occupied regions. In Roomvent 94 Proceedings of the Fourth International Conference on Air Distribution in Rooms, vol. 2. Krakow, Poland. 

System effect The effect that system components and/or the room have on the air quantity and pressure delivered to the space. 

The key questions to be answered are Is the system effective and Is it suitable to continue without change At every meeting of the review team these questions should be answered and the response recorded. 

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