Ventilation


The best way to avoid fugitive emissions is by using leak-tight equipment (e.g., changing from packing to mechanical seals or even using sealless pumps, etc.). If this is not possible, then regular maintenance checks can reduce fugitive emissions. If all else, fails, the equipment can be enclosed and ventilated. The air would then be treated before finally passing to the atmosphere. Storage tanks should be prevented from breathing to atmosphere. There are three broad methods which allow this to be achieved  [c.260]

The first system was ordered in late March 1995, was available for field use on June 16, and was first used in actual waste sampling operations in early July 1995. The other three systems were delivered during November and December of 1995 and were all deployed by January 12, 1996. Approximately twenty ergonomic and electrical/mechanical changes were supplied with the latter three systems. These changes included a relocation of the display monitors, the S-VHS recorder, and the thermal image printer. The major mechanical changes included the addition of enclosed fork-lift pockets in the cabinet s frame, additional control cabinet ventilation, and a slight increase in the size of the lower control cabinet console which allowed for relocation of the 160 kV x-ray power supply and the refrigerated, x-ray tube cooling unit.  [c.610]

The changes described above also allowed much easier access to the high voltage cable for routine (6-month) owner directed, service operations, and provided better upper and lower x-ray cabinet and control cabinet ventilation. With the exception of the x-ray tubes, all the individual manufactured components, on all four systems are identical. There are very subtle differences in the warm-up/start-up sequence on the x-ray controllers on the newer systems due to model/year and x-ray tube differences. The last three systems were supplied with environmental type key-boards for the image processors and base-mounted , rather than conduit-mounted exterior warning indicators. The first system was subsequently upgraded to include the better keyboard and the external warning appliances/features.  [c.611]

Hydrogen bromide. Method 1 (by direct combination of hydrogen and bromine). This gas may be readily prepared by passing a mixture of hydrogen and bromine vapour through a hot tube packed with porous porcelain chips excess of bromine is removed by passage through a tube containing copper turnings. The apparatus is illustrated in Fig. II, 48, 2. A is a 125 ml. Pyrex distilling flask of which the side arm has been bent into a horizontal position. It is immersed into a 800 or 1000 ml. beaker, which acts as a water bath. The distilling flask is fitted with a two-holed rubber stopper carrying a 50 ml. dropping funnel and a tube bent twice at right angles leading to a safety bottle C. The safety bottle is charged with water (or some other suitable liquid) and has an outlet tube for hydrogen in case an obstruction is formed in the apparatus the outlet tube must be connected to a tube leading directly to the ventilation shaft (fume cupboard). The side arm of the distilling flask is fitted by means  [c.180]

Zinc is not considered to be toxic, but when freshly formed ZnO is inhaled a disorder known as the oxide shakes or zinc chills sometimes occurs. Where zinc oxide is encountered, recommendations include providing good ventilation to avoid concentration exceeding 5 mg/ms, (time-weighted over an 8-hour exposure, 40-hour work week).  [c.54]

The element and its compounds are toxic and should be handled carefully. Contact of the metal with skin is dangerous, and when melting the metal adequate ventilation should be provided. Exposure to thallium (soluble compounds) - skin, as Tl, should not exceed 0.1 mg/ms (8-hour time-weighted average - 40-hour work week). Thallium is suspected of carcinogenic potential for  [c.145]

Care must be taken in handling radon, as with other radioactive materials. The main hazard is from inhalation of the element and its solid daughters which are collected on dust in the air. Good ventilation should be provided where radium, thorium, or actinium is stored to prevent build-up of the element. Radon build-up is a health consideration in uranium mines. Recently radon build-up in homes has been a concern. Many deaths from lung cancer are caused by radon exposure. In the U.S. it is recommended that remedial action be taken if the air in homes exceeds 4 pCi/1.  [c.153]

Drain Opener. This reaction MUST be performed in an area of adequate upward ventilation, or at feast with the air flowing away from you.  [c.266]

CAUTION - Formaldehyde and ammonia solutions are extremely poisonous and quite noxious. Perform this step in a well-ventilated area (outside or with direct exhaust of the fumes)  [c.276]

Even minute amounts of ethylene can stimulate ripening and the rate of ripening increases with the concentration of ethylene This property is used to advantage for example in the marketing of ba nanas Bananas are picked green in the tropics kept green by being stored with adequate ventilation to limit the amount of ethylene present and then in duced to ripen at their destination by passing ethyl ene over the fruit  [c.189]

Over the years, many people have been exposed to low levels of these furan derivatives with no evidence of any significant long-term effects. Proper precautions, however, should be taken when working with these compounds as furfural, furfuryl alcohol, and furan are moderately toxic, tetrahydrofurfuryl alcohol is less so. Protective clothing should be worn skin absorption is a likely route of entry. Eye protection is required. Proper ventilation is needed, especially with highly volatile furan. The odor threshold for these compounds is such that they can be detected at levels below the PEL (Permissible Exposure Level), and appropriate action taken as soon as the odor is detected. Specific recommendations from the manufacturer regarding exposure and protective measures should be foUowed. Since regulations change from time to time, up-to-date exposure limit recommendations from OSHA (Occupational Safety and Health Agency) or ACGIH (American Council of Governmental Industrial Hygienists) need to be consulted and foUowed.  [c.83]

Another class of adhesives has been gaining more widespread use in the wood laminates and composites industries. These adhesives are isocyanates, the common name of a chemical group of diphenyHnethane-/), -diisocyanate polymers. They are exceUent adhesives, fast-curing, and wiU produce durable, waterproof bonds if used in sufficient quantity. Considerations which have slowed wider usage of isocyanates are high cost (about 6x urea resins and 3x phenol resins) adhesive quaHties which bonds to press plates as easily as to wood, thus requiring a totaUy reHable press release additive system and finaUy, their toxic characteristics require a high level of manufacturing safeguards. The Hquid adhesive should not contact the skin, and whereas only very minor amounts of odorless emissions occur during appHcation and curing, about 4% of exposed persons are sensitive to these fumes and may develop a life-threatening asthmatic condition on continued exposure. However, their fast curing rate offsets some of the higher cost as compared to phenoHcs, and the other primary concerns can be handled by special care in monitoring, handling, and dust/ventilation controls. Provided they are used properly and safely, isocyanates have been found to be exceUent bonding agents.  [c.378]

In addition to the previously noted safety factors associated with these processes, there are additional needs for dust control and ventilation for dissipation of various vapors from pressing, tempering/heat treatment, and machining and finishing operations.  [c.390]

Health and safety factors in the OSB industry are similar to those in other composite mills. Worker safety caimot be stressed too highly, a main component of which is to develop an awareness in the workers to be prepared for danger at all times. Many accidents are the result of a moment of careless or unthinking activity on the part of the person injured or another nearby person. An area of special concern in some OSB mils, those using isocyanate adhesives, is awareness of the toxic nature of this adhesive in the uncured state and the requirements of personal care, housekeeping, and ventilation and air handling in the process areas from blending through pressing.  [c.396]

Acetone can be handled safely if common sense precautions are taken. It should be used in a weU-ventilated area, and because of its low flash point, ignition sources should be absent. Flame will travel from an ignition source along vapor flows on floors or bench tops to the point of use. Sinks should be rinsed with water while acetone is being used to clean glassware, to prevent the accumulation of vapors. If prolonged or repeated skin contact with acetone could occur, impermeable protective equipment such as gloves and aprons should be worn.  [c.98]

The following cautions should be observed Do not destroy or remove inhibitor. Do not contaminate with alkaline or strongly acidic materials. Do not store in the presence of a water layer. In the event of spillage or misuse that cause a release of product vapor to the atmosphere, thoroughly ventilate the area, especially near floor levels where vapors will collect.  [c.129]

Handling of dry acrylamide is hazardous primarily from its dust and vapor, and this is a significant problem, especially in the course of emptying bags and dmms. This operation should be carried out in an exhaust hood with the operator wearing respiratory and dermal protection. Waste air from the above mentioned ventilation should be treated by a wet scmbber before purging to the open air, and the waste water should be fed to an activated sludge plant or chemical treatment faciUty. SoHd acrylamide may polymerize violendy when melted or brought into contact with oxidizing agents. Storage areas for sohd acrylamide monomer should be clean and dry and the temperature maintained at 10—25°C, with a maximum of 30°C.  [c.136]

Full eye protection should be worn whenever handling acryhc monomers contact lenses must never be worn. Prolonged exposure to Hquid or vapor can result in permanent eye damage or blindness. Excessive exposure to vapors causes nose and throat irritation, headaches, nausea, vomiting, and dizziness or drowsiness (solvent narcosis). Overexposure may cause central nervous system depression. Both proper respiratory protection and good ventilation are necessary wherever the possibiHty of high vapor concentration arises.  [c.157]

In normal practice, good ventilation to reduce exposure to vapors, splash-proof goggles to avoid eye contact, and protective clothing to avoid skin contact are required for the safe handling of acrylic monomers. A more extensive discussion of these factors should be consulted before handling these monomers (67).  [c.165]

Acrylonitrile must be stored in tightly closed containers in cool, dry, weU-ventilated areas away from heat, sources of ignition, and incompatible chemicals. Storage vessels, such as steel dmms, must be protected against physical damage, with outside detached storage preferred. Storage tanks and equipment used for transferring acrylonitrile should be electrically grounded to reduce the possibiUty of static spark-initiated fire or explosion.  [c.185]

Acrylonitrile is combustible and ignites readily, producing toxic combustion products such as hydrogen cyanide, nitrogen oxides, and carbon monoxide. It forms explosive mixtures with air and must be handled in weU-ventilated areas and kept away from any source of ignition, since the vapor can spread to distant ignition sources and flash back.  [c.185]

Until recently most industrial scale, and even bench scale, bioreactors of this type were agitated by a set of Rushton turbines having about one-thind the diameter of the bioreactor (43) (Fig. 3). In this system, the air enters into the lower agitator and is dispersed from the back of the impeller blades by gas-fiUed or ventilated cavities (44). The presence of these cavities causes the power drawn by the agitator, ie, the power requited to drive it through the broth, to fall and this has important consequences for the performance of the bioreactor with respect to aeration (35). k a has been related to the power per unit volume, P/ U, in W/m and to the superficial air velocity, in m/s (20), where is the air flow rate per cross-sectional area of bioreactor. This relationship in water is  [c.334]

An analysis of the building stmcture must be conducted to determine the effects of heat gain from the sun. This analysis includes building orientation, type of constmction, surrounding vegetation and stmctures, and reflective surfaces. People, lighting, machinery loads, and heat gains from chemical processes are evaluated as well as hooded (ventilated) processes, and lengths of operation. Outdoor air requited both for ventilation to remove odors and contaminants, and for replacement of air exhausted through hoods must be conditioned. ASHRAE Standard 62 (8) provides recommendations for minimum outdoor air requirements local codes should be investigated. A building often requites cooling at low outdoor temperatures as a result of high internal heat gains. Interior portions of many buildings requite cooling during occupied hours throughout the year. The use of outdoor air, when its temperature and dew point ate suitable (economizer cycle), is an efficient means of air conditioning. Cate must be taken, however, in applying economizer cycles to areas where close humidity control is requited because additional humidification or dehumidification may be needed.  [c.360]

Typical Air Conditioning Systems. Two broad categories of air conditioning systems exist, unitary and apphed. Unitary systems ate self-contained units that are "off the shelf." They use electricity for cooling, and may use electricity, natural gas, fuel oil, or propane for heating. Heat rejected during the cooling cycle is dissipated to the outdoors. Multiple unitary systems may be employed to provide greater overall rehabihty and to permit individual control of various sections of a plant. A typical unit for rooftop mounting is shown in Figure 5. It contains means for heating, ventilating, and cooling.  [c.361]

More flexibility is obtained with apphed equipment (Fig. 6), which is normally used to condition a relatively large area of a plant. This is usually part of a "field erected" system. In apphed systems, outdoor air for ventilation or cooling (economizer cycle) is drawn through a preconditioning or preheat coil and mixed with air returned from the conditioned space. Dampers regulate the relative amounts of outdoor and recycled air for temperature control. The air is filtered before passing into the conditioning section which contains cooling and dehumidifying coils, air washers for humidity control, and heating cods. Bypass of return air may be included for temperature control. The refrigerating effect is provided in one of several ways. WeU water may be employed if avadable in sufficient quahty and quantity and at a suitable temperature. More commonly, refrigerating machines or "chillers" are used. In small systems, reciprocating compressors are employed and the refrigerant maybe directly admitted to the cooling cod. In larger apphcations, water is chilled and circulated through the central station unit. For apphcations in excess of 350 kW (1.2 x 10 Btu/h), reciprocating compressors may be replaced by centrifugal systems. Most systems are electrically powered however, steam or gas turbines are used occasionally. Absorption chillers are frequently used when a suitable supply of "waste" heat is avadable. Low pressure steam, hot water, and process streams may provide the motive force. Solar heated water is also finding apphcation (9) (see Solarenergy).  [c.361]

Use Equipment Only When deeded. Start morning warm-up no earHer than necessary and do not use outside air for ventilation until the building is occupied. Use minimum amounts of outdoor air according to reference 8. Supply heat at night only to maintain a temperature above 13°C. Supply Heating and Cooling from the Most Efficient Source.  [c.362]

A Bibliography of Available Computer Programs in the Area of Heating, Ventilating, Air Conditioning and Refrigeration, American Society of Heating, Refrigerating, and Air Conditioning Engineers, Inc., 1986.  [c.364]

R. W. Haines, Control Systems for Heating Ventilating and Air Conditioning, Van Nostrand-Reinhold, New York, 4th ed., 1987.  [c.365]

In 1997 a fly-ash storage silo (Fig. 4) at a German power-plant was damaged by a pressure-overload during filling. The silo was built in 1974 as a slipform eonerete construetion. In aeeordance to the newest technology of tlie times tlie built-in sliding ducts had not been filled with mortar or cement paste during construction. For the repair it was necessary to inject these ducts with cement paste. For injection and ventilation it became necessary to drill holes at both ends of the ducts.  [c.754]

According to these preliminary testings, we proposed the following procedure. Because there was only slight cracking at the upper section of the silo (marked in Fig. 7), it would be most promising to start the testing there. In the case of dectecting significant echos from a duct, we would drill directly into the building on trial to test the result. Furthermore, it was assumed that the ducts would lie completely vertically. Because there was a poor chance of the ultrasound-testing beeing successful at the lower, extremly cracked injection area, it was proposed to localize the ducts there by connecting the positions found in the upper section vertically down to the lower section with a vertical lead line (distance ca. 15m). After marking the measured position of the ducts, they should be found by drilling on trial there as well. In the same way, the holes for the ventilation during injection, at the top of the building should be drilled.  [c.755]

The following work of drilling the final holes for the injection and ventilation was carried out by manual labours according to the orders described above. The owner returned a positive result for this operation, especially the orientation of the ducts in the building being ab.solutly vertical, henceforth the proposed procedure succeeded.  [c.757]

One gram of radium produces about 0.0001 ml (stp) of emanation, or radon gas, per day. This is purged from the radium and sealed in minute tubes, which are used in the treatment of cancer and other diseases. Radium is used in the producing of self-luminous paints, neutron sources, and in medicine for the treatment of disease. Some of the more recently discovered radioisotopes, such as 60Co, are now being used in place of radium. Some of these sources are much more powerful, and others are safer to use. Radium loses about 1% of its activity in 25 years, being transformed into elements of lower atomic weight. Lead is a final product of disintegration. Stored radium should be ventilated to prevent build-up of radon.  [c.156]

Specifications, Standards, Quality Control, and Health and Safety. The Hardwood Plywood and Veneer Association (HPVA) represents the manufacturers and associated industries in matters relating to specifications, standards, quaHty control, and health and safety factors. Specifications and standards for hardwood plywood products are found in the American National Standard Institute (ANSI) standard for Hardwood and Decorative Plywood (3). The most important product quaHty test procedures are bond quaHty tests and the formaldehyde emission test. The formaldehyde emission test is described in ASTM E1333-90 (4). Test panels are placed in a test chamber maintained at 25°C, 50% relative humidity (rh), 0.5 air change per hour, and having a test product loading rate of 0.95 m of product surface/m of chamber volume, ie, 0.95 m /m. These are considered to be normal conditions of temperature, rh, air ventilation rate, and product usage within a manufactured home. Eormaldehyde concentrations within the test chamber must be <0.20 //L/L (ppm) to qualify the material for use in manufactured homes. At the time of this writing (ca 1997), there is no emission regulation for products used in other buildings, but the majority of products are now manufactured to pass this stringent emissions test. Another important test is the flamespread test, described in ASTM E-84 (5). This test is designed to measure the potential of a product to ignite and contribute to the spread of a flamefront in a fire.  [c.382]

The 2-cyanoacryhc esters have sharp, pungent odors and are lacrimators, even at very low concentrations. These esters can be irritating to the nose and throat at concentrations as low as 3 ppm eye irritation is observed at levels of 5 ppm (13). The TLV for methyl 2-cyanoacrylate is 2 ppm and the short-term exposure limit is 4 ppm (14). Good ventilation when using the adhesives is essential.  [c.178]

E. C. McQuiston and J. D. Parker, Heating, Ventilating and Air Conditioning, 3rd ed., John Wiley Sons, Inc., New York, 1988.  [c.364]


See pages that mention the term Ventilation : [c.612]    [c.529]    [c.43]    [c.1133]    [c.81]    [c.175]    [c.530]    [c.84]    [c.157]    [c.267]    [c.1184]    [c.1050]    [c.224]    [c.360]    [c.361]    [c.364]   
See chapters in:

Plant Engineer's Handbook  -> Ventilation


Fundamentals of air pollution (1994) -- [ c.0 ]

Hazardous chemicals handbook Изд.2 (2002) -- [ c.0 ]

Industrial ventilation design guidebook (2001) -- [ c.0 ]

What went wrong (0) -- [ c.20 , c.54 , c.69 , c.147 , c.169 , c.232 , c.242 , c.249 , c.277 , c.318 , c.345 ]