Dilution, safe

Early decisions made purely for process reasons often can lead to problems of safety and health (and environment) which require complex and often expensive solutions. It is far better to consider them early as the design progresses. Designs that avoid the need for hazardous materials, or use less of them, or use them at lower temperatures and pressures, or dilute them with inert materials will be inherently safe and will not require elaborate safety systems. ... 

Designs that avoid the need for hazeudous materials, or use less of them, or use them at lower temperatures and pressures, or dilute them with inert materials will be inherently safe and will not require... 

Lowering the temperature below the boiling point or diluting it with a safe solvent... 

Freshly opened bottles of these reagents are generally of the concentrations indicated in the table. This may not be true of bottles long opened and this is especially true of ammonium hydroxide, which rapidly loses its strength. In preparing volumetric solutions, it is well to be on the safe side and take a little more than the calculated volume of the concentrated reagent, since it is much easier to dilute a concentrated solution than to strengthen one that is too weak. 

The organic peroxides and peroxide compositions produced commercially are those that can be manufactured, shipped, stored, and used safely. Organic peroxides can be thermally and mechanically desensitized by wetting or by dilution with suitable solvents, iaert soHd fillers, or iasoluble Hquids (suspension of soHd peroxides ia Hquid plasticizers or water, and emulsions of Hquid peroxides ia water). 

Sahcyhc acid USP, EP, and other pharmacopeia grades are used medically as antiseptic, disinfectant, antifungal, and keratolytic agents. Sahcyhc acid is formulated in lotion or ointment formulations for the treatment of dandmff, eczema, psoriasis, and various parasitic skin diseases. Because the keratolytic property of this aromatic acid has use in the safe removal of dead skin cells from the surface of healthy skin, the acid is used in concentrated sahcyhc acid solutions or suspensions to remove warts and corns. In more dilute form, sahcyhc acid preparations have found use in dandmff and eczema treatment. Sahcyhc acid has been considered and found effective by the Advisory Committees to the FDA in various over-the-counter (OTC) dmg regulated uses. Among these are acne products, dermatitis, dry skin, dandmff and psoriasis products, and foot care products (24). 

When it approved the New Animal Drug AppHcation (NADA) of formalin, FDA ruled that use of formalin for fisheries was safe for humans and the environment. They ruled that effluents from fish treatments at 250 mg/L should be diluted 10 times and from egg treatments 75 times if 1,000 —2,000 mg/L were used (10,11). Before registering the compound, FDA also addressed carcinogenicity by stating it was not concerned about human exposure from either water or fish treated with formalin. The U.S. Fish and Wildlife Service (USFWS) has procedural guidelines that should protect workers from harm fill levels of formalin. Calculations based on treatment levels demonstrated that a fishery worker is exposed to not more than 0.117 mg/L formalin in the air, well below the levels estabUshed by the U.S. Occupational Safety and Health Administration to protect workers. 

SpiHs can also be diluted with large volumes of water. Care should be taken, however, because chlorosulfuric acid reacts violentiy with water Hberating heat, hydrochloric acid, and sulfuric acid mists and steam. The water should be appHed from a safe distance upwind of the spiH using a fog no22le. Remaining traces of acid should be neutrali2ed with soda ash, caustic soda, or lime before disposal. 

Personnel are protected in working with tritium primarily by containment of all active material. Containment devices such as process lines and storage media are normally placed in well-ventilated secondary enclosures (hoods or process rooms). The ventilating air is monitored and released through tall stacks environmental tritium is limited to safe levels by atmospheric dilution of the stack effluent. Tritium can be efficiently removed from air streams by catalytic oxidation followed by water adsorption on a microporous soHd absorbent (80) (see Absorption). 

Safe dilution requirements can be given for the gas phase in a flammability diagram or equation (270,273). Alternatively, safe vapor dilution can be given in terms of the Hquid storage conditions where allowance can be made for solubility of the inert gas in Hquid ethylene oxide (273). 

Minimize disposal requirements by careful estimation of needs and correct measurement Dispose of dilute pesticides by using as a spray, in accordance with approval, in a safe/approved area Concentrated, unused pesticides should be stored, returned or disposed of as toxic waste... 

Any waste material (and contaminated cloths, tissues, clothing etc.) must be rendered safe by chemical means or by controlled incineration of dilute solution where practical prior to disposal. 

Turn off the source of the leak and limit the spread of fluid by means of mop, dusters, rags, sand or diversion Absorb spillage and shovel into buckets, and remove to a safe place, dilute greatly with running water and/or dilute with dispersing agent and water (as with ammonia solution, ethanol, methanol and formaldehyde solution)... 

Dilution ventilation or general exhaust ventilation A mixed airflow designed to dilute the contaminants within a space to required safe concentration... 

Blowdown from the boiler(s) should always be taken to either a blowdown sump or blowdown vessel before discharging into drains. Both should be adequately sized to give cooling by dilution and be fitted with vent pipes to dissipate pressure safely. The boiler(s) should have independent drain lines for the main manually operated blowdown valve and the drains from a continuous blowdown system. Where more than one boiler is connected to either system the line should be fitted with a check or secondary valve capable of being locked. 

Dilution of fumes in these areas is generally required for one of two reasons either to reduce the level of harmful (toxic or irritant) fumes to a safe level, normally below the OES (Occupational Exposure Standard) or to dilute offensive odors. Care must be taken with the latter to ensure that the problem is not merely passed on to neighbors. If it is, then a local extract with air-cleaning equipment will be preferred if it is practical. Indeed, a local extract system is always preferable, since it removes the problem at source, resulting in a cleaner environment within the building. 

The irradiation (or ion bombardment) of solid solutions, where a scavenger can be present, should also be explored further. Here it will be important to ensure that the solids are indeed solutions before conclusions can be safely drawn. It is curious to note that the yields observed in frozen solutions are in several cases very similar to the yields in the pure crystalline solutes. This suggests the possibility that the frozen targets had segregated, and that the solute was in fact present as micro crystals. (If this is the case, it may well be that a new method can be developed on this basis for making phase studies at high dilution.)... 

Dispose of dilute pesticides by using as a spray, in accordance with approval, in a safe/ approved area... 

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