bluuebunny/crossref_metadata_2025 huggingface dataset:
The Multiaxial Equivalent of Stressed Volume
Authors: Tucker WT , Johnson CA
Published: March 2009

A comprehensive probabilistic fracture analysis methodology should allow data to be combined or pooled from multiple specimen sizes and geometries such that all available fracture data can be integrated into strength/probability estimates and such that size-scaling aspects of the model can be tested. Moreover, this capability must, among other things, allow for multiaxial stress states, and be be capable of providing a measure of the statistical uncertainty in estimates of strength and/or probability including confidence and tolerance bounds. Previous efforts of the authors have produced estimators for combined data, confidence and tolerance bounds on estimates, bias and bias correction of estimates and measures of statistical efficiency of the estimators. These developments have been based on Weibull's uniaxial model involving k, a dimensionless “load factor” or “structure factor.”

The results presented in this paper show that similar techniques are applicable to more comprehensive models of multiaxial failure. Building on previous work by the first author, reported elsewhere, and generalizing results recently reported in the literature, it is shown that the Batdorf-Heinisch's (B-H) flaw density distribution and the Lamon-Evans' (L-E) elemental strength approaches to weakest-link fracture statistics for multiaxial loading give equivalent probability predictions for equivalent failure criteria. A generalization is also given detailing necessary and sufficient conditions for the B-H and L-E approaches to be equivalent. This allows a general size factor to be defined that simultaneously takes into account geometry, loading, and multiaxial stresses. This general size factor replaces k in the estimators for combined data, confidence and tolerance bounds on estimates, bias and bias correction of estimates and measures of statistical efficiency previously developed by the authors. It can be applied on an elemental basis or to a component structure as a whole, and this has consequences in determining probability predictions. Also employing these results, it is indicated how a contradictory conclusion, also reported in the literature, was reached. All in all, there appear to be no obvious roadblocks in incorporating the effects of multiaxial stresses into current analysis methods. Moreover, the form of the generai size factor indicates that it may be possible to obtain generalizations that cover time and/or temperature effects. Thus, the equivalence of the B-H and L-E formulations has broad reaching implications.
Effect of Proof Testing on the Failure Probability of Multiaxially Loaded Ceramic Components
Authors: Brückner-Foit A , Heger A , Munz D
Published: March 2009

The effect of proof testing on the probability of fast fracture of ceramic components subject to multiaxial loading is analyzed using multiaxial Weibull theory. A local risk of fracture is defined which corresponds to the probability that failure of the component considered is caused by a flaw located at a given point in the structure. The failure behaviour after proof testing is discussed using two simple examples. It is shown in which way the efficiency of the proof test is related to the local risk of fracture during the proof test and under operating conditions.
Predicting Creep Behavior of Silicon Nitride Components Using Finite Element Techniques
Authors: Wade JA , White CS , Wu FJ
Published: March 2009

The creep of silicon nitride tensile specimens has been modeled and incorporated into finite element software to predict the behavior of structural components. The experimental results are for the creep deformation of HIP'ed, yttria-doped silicon nitride at temperatures up to 1400°C. Results are for both homogeneous and joined specimens. This experimental data base was modeled using two approaches: Arrhenius law representation of the steady state phase, and theta projection method representation of both primary and secondary stages. The Arrhenius law has been incorporated into commercial finite element software and used to predict the creep deformation behavior and time to failure for a simulated component represented by a notched tensile specimen.
Time-Dependent Reliability Analysis of Monolithic Ceramic Components Using the Cares/Life Integrated Design Program
Authors: Nemeth NN , Powers LM , Janosik LA , Gyekenyesi JP
Published: March 2009

The computer program CARES/LIFE calculates the time-dependent reliability of monolithic ceramic components subjected to thennomechanical and/or proof test loading. This program is an extension of the CARES (Ceramics Analysis and Reliability Evaluation of Structures) computer program. CARES/LIFE accounts for the phenomenon of subcritical crack growth (SCG) by utilizing either the power or Paris law relations. The two-parameter Weibull cumulative distribution function is used to characterize the variation in component strength. The effects of multiaxial stresses are modeled using either the principle of independent action (PIA), Weibull's normal stress averaging method (NSA), or Batdorf's theory. Inert strength and fatigue parameters are estimated from rupture strength data of naturally flawed specimens loaded in static, dynamic, or cyclic fatigue. Two example problems demonstrating component reliability analysis and fatigue parameter estimation are included.
Annual Survey of Catastrophic Football Injuries: 1977–1992
Authors: Mueller FO , Cantu RC
Published: March 2009

Football catastrophic injuries may never be totally eliminated, but continued research has resulted in rule changes, equipment standards, improved medical care both on and off the playing field, and changes in teaching the fundamental techniques of the game. These changes were the results of a united effort by coaches, administrators, researchers, equipment manufacturers, physicians, trainers and players.

Research based on reliable data is essential if progress is to be made. Research provides data that indicate the problems and reveal the adequacy of preventive measures.
Spinal Injuries in Ice Hockey: Review of 182 North American Cases and Analysis of Etiological Factors
Authors: Tator CH , Edmonds VE , Lapczak L
Published: March 2009

This paper describes 182 cases of spinal injuries in North American ice hockey players occurring between 1966 and 1991. One hundred and seventy-three injuries occurred in Canada, 8 in the United States, and one Canadian player was injured in a game in Germany. The median age of the players was 18 and 96% were males. One hundred and thirty-eight had neck injuries. The majority of the injuries occurred in games in organized leagues. Spinal cord injury occurred in 106 cases, 51 of whom had complete spinal cord injuries. Collision of the helmeted head with the boards, especially following a check or push from behind, was the most common mechanism of injury. It is felt that most of these injuries are preventable.
The National Electronic Injury Surveillance System (NEISS) and Hazard Analysis
Authors: Frye RE
Published: March 2009

This paper describes the design and operation of the U.S. Consumer Product Safety Commission's National Electronic Injury Surveillance System (NEISS), the development of national estimates and data on injuries, associated with products used in recreational and residential settings, and the identification of reasonable approaches to reducing the frequency and severity of injuries and deaths. The NEISS is a national probability sample of 91 hospitals which provide data on over 280,000 case reports each year. It is a multi-level data collection system, including extracts from hospital emergency room records, telephone follow-ups to injured persons, and on-site in-depth investigations of specific cases of interest. Examples are given on the development of national estimates and trends in injuries for such products as fireworks, playground equipment, and all-terrain vehicles. The identification of incident hazard patterns for specific sports activities or product types and the development of remedial efforts are discussed. These efforts may involve new product safety standards, public information and educational activities, or other steps to reduce unreasonable risks of injury. A description of how to obtain NEISS data and copies of CPSC reports from the National Injury Information Clearinghouse is included.
Causes of Pool Diving Accidents
Authors: Gabrielsen M , Mittelstaedt AH
Published: March 2009

Increasing research into diving injuries and fatalities as revealed in litigation over the years, can provide an insight into prevention and correction of the causes.
A Uniform Minimum Safe Diving Depth for Swimming Facilities
Authors: Gilbert RR
Published: March 2009

Sports medicine physicians have estimated as many as 1 800 spinal cord injuries from “shallow water” diving annually in our country. These injuries are devastating (usually high cervical injuries) resulting in quadriplegia. This high number of injuries is unacceptable and preventable. It is preventable by establishing a minimum safe diving depth in all bodies of water of 5 feet. The minimum depth of 5 feet has been recognized by a number of state public health codes and has been statistically documented by research and studies done by Dr. Milton Gabrielsen through Nova University. The establishment of a minimum safe diving depth is a “passive” safety system which promises to greatly reduce and eliminate the tragedy, economic loss, litigation resulting from the spinal cord injuries, and also result in millions of dollars of savings of medical care and costs for these tragic quadriplegic victims. In addition to a number of state public health codes, the American Red Cross and the Aquatic Injury Safety Group have advocated a minimum diving depth of 5 feet for many years. The establishment of a minimum safe diving depth of 5 feet does not eliminate diving, but rather promotes safe diving.
Cerebral Concussions in Taekwondo Athletes
Authors: Zemper ED , Pieter W
Published: March 2009

Injury and exposure data were collected at eight major U.S. taekwondo tournaments between 1988 and 1990, involving 5 682 competitors and a total of 5 566 bouts. There were 802 recorded injuries, 292 (36%) severe enough to cause time-loss of one day or more from further participation. Injuries were equally divided between the head and lower extremities, each accounting for about 40% of the injuries, with the remainder to upper extremities and the body. Cerebral concussions were among the most serious injuries observed, with 58 recorded or approximately 1 for every 100 participants. The total cerebral concussion rate was 5.2/1 000 athlete-exposures or 1.1/1 000 minutes of exposure. These rates of concussions for taekwondo are 3.1 times higher than seen in college football games based on number of exposures, and 7.9 times as high based on time of exposure.
The Application of Rodent Models to the Study of Brain Injury Bimechanics.
Authors: Dixon CE
Published: March 2009

The primary objective of this investigation was to determine the relative contributions of contact velocity and compression to acute neurological deficits and gross histologic changes following either central or lateral cortical impact with systematic, independent variations of contact velocity and depth of deformation. To investigate the response to midline and lateral cortical impact, rats were injured, under anesthesia, at 1 of 18 different combinations of impact velocity and compression parameters. Following injury, neurological response and the contusional state of the brain was noted. For both studies, acute neurologic responses correlated better with velocity compression product (VC) than with either velocity or compression alone. At low contact velocity, functional impairment is best predicted by maximal compression. However, as velocity increases, injury severity becomes a function of (VC), demonstrating the rate sensitivity of brain tissue. The central and lateral impact data support the viscous response (VmaxCmax) as a biomechanical predictor of rat brain injury.
Buckling Analysis -- A Modal Method of Estimating Cervical Spine Injury Potential
Authors: Voo LM , Liu YK
Published: March 2009

The whole straightened ligamentous cervical spinal column (C0/C1-T1) was represented by a three-dimensional segmented beam-column computer model, where vertebral bodies were treated as three-dimensional rigid body elements and intervertebral joints as three-dimensional joint elements having stiffness in axial compression-tension, antero-posterior and lateral shears, and flexural rotations (flexion-extension and lateral bending). Buckling modal analysis of this model estimated the potential responses of the cervical spine subjected to “axial” head impact. The calculated theoretical buckling loads are in agreement with the peak forces obtained in some of the in vitro cadaveric experiments of the cervical spine subjected to axial compressive loading.
The Effect of Head Position on the Analysis of Cervical Motion
Authors: Ordway NR , Edwards WT , Donelson RG , Bosco M
Published: March 2009

The motion of the head and neck until injury, or the threshold of injury is normally limited by the tension of soft tissues along the cervical spine and by any obstruction. The relative range of motion (ROM) available during loading until injury is dependent partially upon the initial starting position and the combinations of motions. In this study, an electromagnetic six degree of freedom digitizer was used to quantitatively assess the effect of head position on cervical spine ROM measurements for a group of 25 subjects with no known cervical symptoms. Forward sagittal translation of the head with respect to the thorax (protrusion) diminished the amount of extension motion available by 4.6°/cm. Backward sagittal translation of the head (retraction) diminished the amount of flexion motion available by 6.1°/cm. In addition, when the head was axially rotated losses of approximately 50% were displayed for measurements of flexion, extension, and lateral bending. This paper illustrates the importance of a defined starting head position when measuring cervical motion and the effects of combined motions. Accurate cervical ROM measurements will be influential in the design of sports equipment and in determining mechanisms of injury.
Accident Performance of Motorcycle and Bicycle Safety Helmets
Authors: Hurt HH , Thom DR
Published: March 2009

Motorcycle and bicycle safety helmets must adhere to specific technical requirements in order to provide protection. Various helmet configurations illustrate success with the application of these principles as well as failure by the neglect of these technical principles. The most critical feature of truly protective headgear is the use of a significant amount of energy absorbing material for the liner of the safety helmet. The most successful safety helmets have been built to standards that incorporate these technical requirements as basic performance in the areas of retention systems and impact attenuation. The qualification of the safety helmet to the basic technical requirements insures protection to the covered integument as well as prevention of a class of “contact” injuries including skull fractures and intracranial injuries. In addition, the qualified safety helmet is shown to prevent or reduce most of a class of “inertial” injuries, but with certain limitations of specific rotational injuries which can not be excluded by any protective device.
Jaw-Joint Disorders in Contact-sports' Athletes. Diagnosis and Prevention
Authors: Williams ED
Published: March 2009

Clinical and radiologic findings in contact-sports' athletes who sustained injury to the Vital Cranial Triad (VCT), a complex of bones consisting of the temporomandibular joint (TMJ), the tympanic temporal bone and the inferior surface of the petrous temporal bone, were studied. Approaches to the diagnosis of temporomandibular disorders focused on findings from patient history, clinical examination and a modified transcranial radiographic examination. Indications for radiography included headache, earache, nausea, vomiting, vertigo, impaired hearing and balance, muscle weakness, occlusal disturbances, TMJ pain and other symptoms associated with neurologic and circulatory deficit secondary to trauma. Radiologic findings included compression fractures, condylar neck fracture, degenerative condylar remodeling, obliteration of the articular eminence, atresia of the ear canal and other damage to the VCT. Structural damage to the VCT is described and the associated symptoms are discussed in the context of 4 exemplary cases. The use of a customized mandibular orthopedic repositioning appliance to prevent injuries to the VCT is discussed. Damage to the VCT leads to painful and tragic sequelae which can and must be prevented in contact sports.
Surface Pretreatment and Adhesive Bonding of Carbon Fiber-Reinforced Epoxy Composites
Authors: Chin JW , Wightman JP
Published: March 2009

Due to the nature of the matrix in carbon fiber-reinforced polymeric composites, conventional methods of joining, such as riveting, bolting or soldering, are not always suitable in structural applications. The preferred method to date is adhesive bonding. The objective of this research is to evaluate the effect of surface pretreatment on the epoxy composite/adhesive interphase. Composite surface pretreatments which were evaluated include grit blasting, peel ply and plasma treatment. The results of lap shear and wedge testing in various environments were correlated to the surface composition after pretreatment, as measured by surface sensitive analytical techniques such as x-ray photoelectron spectroscopy, ion scattering spectroscopy, contact angle analysis, profilometry and scanning electron microscopy.
Correlating the Dynamic Rheological Properties of Adhesives and Substrates to Explain Bond Strengths
Authors: Cherutich C
Published: March 2009

A long term objective of our work is to show that the properties of an adhesive can be used as the primary formulating guide to develop adhesives that bond well to a variety of thermoplastics. It is also postulated that bond strengths would be influenced to a great extent by the rheological properties of the substrate, consequently, given a substrate, one would formulate an adhesive not so much by chemical modifications but by rheological modifications. This paper demonstrates that the bond strength of a lap shear joint at a given time and temperature can be correlated with the rheological properties of the substrate and the adhesive. In the first part of the experiments, the dynamic rheological characteristics of the substrate to be bonded were measured. This substrate was then bonded with an adhesive that cures at several different temperatures. The dynamic properties of the adhesive at these cure temperatures were measured. The bond strength at a specific temperature could be explained by by examining the rheological properties of the adhesive and the substrate. In separate experiments, it was found that the rate of bond strength development of the adhesive was largely independent of the adhesive/substrate combination once effects for the thermal conductivity of the substrate were accounted for.
Repair of Thermoplastic Resin Composites by Fusion Bonding
Authors: Xiao X , Hoa SV , Street KN
Published: March 2009

Methods for the fusion bonding repair of thermoplastic resin composites are discussed. Depending on the damage modes, thermoplastic resin composites may be repaired by welding on a patch or by thermal reforming. The merits and shortcomings of patching by fusion bonding are discussed and compared to those of adhesive patching. Resistance heating and induction heating with susceptors are considered to be suitable for patching type repair. The processing parameters and critical problems for the field repair application of these methods are investigated. Healing type repair, or thermal reforming, is based on the concept of crack healing of polymers. This technique is particularly interesting for repair of delamination. However, healing type repair requires relatively high pressure which can be achieved generally only at well equipped repair depots.
The Effect of Temperature and Humidity on the Fatigue Behaviour of Composite Bonded Joints
Authors: Gilmore RB , Shaw SJ
Published: March 2009

Simulated aircraft structural joints using CFRP adherends and a supported (for bond thickness control) and an unsupported version of a 120°C epoxy adhesive were fatigued at five different combinations of temperature and humidity. These combinations were: ambient dry, and at 85%RH, 90°C dry, and at 65%RH, and -50°C. The high humidity fatiguing made use of a saturated salt humidity chamber specially developed for the purpose.

The joint geometry used was a variation of a cracked-lap shear joint chosen because it simulated actual joints, allowed the progress of fatigue damage to be observed, and was simple to manufacture.

Fatigue damage was monitored and assessed via a combination of microscopy, ultrasonic inspection and radiography.

The results obtained showed that the fatigue behaviour of adhesive joints was considerably affected by temperature, humidity, and support medium. Cohesive failure of adhesive, interfacial failure, and interlaminar failure of adherends were all observed, such that predictions of structural integrity would be difficult to make. In addition, failure modes observed could be aggravated by, or themselves exaggerate, gross defects or inconsistencies already present in a structure, e.g. impact damage. Optimum static performance may not give acceptable fatigue behaviour.
Fractographic Analysis of Surface Preparations on Graphite/Epoxy Composites Used in Adhesive Bonding
Authors: Pinnell WB , Kuhbander RJ , Behme AK
Published: March 2009

Surface preparations of graphite/epoxy composites for adhesive bonding were mechanically tested and fractographically examined. Two adhesives (FM73 and FM300), two peel plies (porous teflon and Release E), and three surface preparations (peel ply, sanding, and an application of a release agent) were considered. Mechanical tests included a standard, single-lap shear specimen and a slightly modified flatwise tensile specimen. Fractographic examinations of the peel plies, prepared surfaces and fracture surfaces were conducted and compared to the mechanical strengths. Results from this investigation showed that the type of peel ply, the surface preparation and the mechanical testing all have an effect on the apparent strength and fracture characteristics of the composite/adhesive bond.
Spectroscopic Study of Sulfate Reducing Bacteria-Metal Ion Interactions Related to Microbiologically Influenced Corrosion (MIC)
Authors: Clayton CR , Halada GP , Kearns JR , Gillow JB , Francis AJ
Published: March 2009

It has long been recognized that sulfate reducing bacteria (SRB) found in natural and industrial waste waters promote microbiologically influenced corrosion (MIC) of certain metals and alloys. Corrosion may be enhanced biologically, through direct enzymatic action of the bacteria, or abiotically, as a result of reaction with metabolic byproducts or changes in local conditions (for example, pH) brought about by bacterial activity. In this study, X-ray photoelectron spectroscopy (XPS) is utilized in conjunction with conventional microbiological and quantitative chemical analytical techniques to analyze the effects of localized environmental conditions similar to those found near the surface of a passive stainless steel on the behavior of SRB, and to determine the ability of these bacteria to alter local environmental conditions in such a way as to create conditions that accelerate corrosion. Specifically, the interactions of Fe, Cr, Ni and Mo ions with Desulfovibrio sp. under anoxic conditions were studied in order to determine the influence of passive dissociation products on the extent of sulfate reduction and to determine the resulting speciation of the metal ions and sulfur. In all cases, XPS revealed the presence of multiple reduced sulfur species (SC2-3, elemental S and S2), as well as reduction of both the molybdate and ferric ions. Localized reduction in pH due to SRB metabolic activity was presumed to play a role in the formation of stable molybdenum disulfide and ferrous species.
Simulation of Microbiologically and Chemically Influenced Corrosion of Natural Sandstone
Authors: Mansch R , Bock E
Published: March 2009

A test system for the simulation of a combined chemically (gaseous pollutants) and microbiologically (nitrifying bacteria) influenced corrosion on natural sandstone is presented. A high stone moisture was essential for the growth of nitrifying bacteria on test stones. Under optimum conditions, a nitrifying biofilm developed on the calcareous Ihrlersteiner green sandstone, reducing the evaporation from the stone surface. Biofilm cells adapted well to high concentrations of gaseous pollutants.

The mean metabolic activities of ammonia oxidizers were 11 and those of nitrite oxidizers 30 times higher than mean values of samples from historical buildings.

The microbiologically influenced nitric acid corrosion alone was stronger than the chemically influenced corrosion by a smog atmosphere (1065-μg/m3 sulphur dioxide, 850-μg/m3 nitric oxide, and about 450-μg/m3 nitrogen dioxide). While 72 μmol of calcium were solubilized per week of exposure to the smog atmosphere, 161 μmol of calcium per week were solubilized by the nitric acid produced by nitrifying bacteria.

If gaseous pollutants were added, the microbiologically produced nitrite and nitrate were removed by the action of sulphur dioxide. Thus, the combined attack of nitrifying bacteria and gaseous pollutants did not result in increased corrosion.
Accelerated Biogenic Sulfuric-Acid Corrosion Test for Evaluating the Performance of Calcium-Aluminate Based Concrete in Sewage Applications
Authors: Sand W , Dumas T , Marcdargent S
Published: March 2009

The corrosion of concrete structures in sewage environments is a major problem in some areas. The phenomena leading to formation and stripping of H2S are now reasonably well understood. By a biologically-influenced process, the metabolism of thiobacilli, hydrogen sulfide is converted into sulfuric acid. This acid reacts with concrete and causes deterioration.

For the purpose of testing materials, this environment is often simulated by laboratory tests with concentrated acid solutions. Such tests, however, do not consider the bacterial aspect of the reality, and therefore, can lead to irrelevant conclusions.

For a reliable result, the interactions between living organisms and their substratum are essential and need to be taken into account. This task is achieved by the use of our simulation chamber for biogenic sulfuric-acid corrosion. The biologically-influenced corrosion is remodeled under conditions favoring the relevant microorganisms. Thus, an acceleration of the natural process is achieved.

Recent investigations conducted on calcium-aluminate-based mortars in the bacterial-corrosion chamber of Hamburg University demonstrated for these materials a good resistance against biogenic sulfuric-acid attack. These results are confirmed by on-site observations of sewer pipelines made of calcium-aluminate-based concrete inspected after up to 35 years of service in harsh environments.
Correlation of Field and Laboratory Microbiologically Influenced Corrosion (MIC) Data for a Copper Potable Water Installation
Authors: Wagner DHJ , Fischer WR , Paradies HH
Published: March 2009

A copper-corrosion process of unknown origin was observed in the cold and warm water supplies shortly after commissioning a county hospital in Germany. The cause of the damage could be attributed to microbial-influenced corrosion (MIC). An evaluation of the damage showed that corrosion is most likely to occur in intensively branched, horizontal pipework during prolonged periods of stagnation. The influences of operating conditions and design installation on the corrosion process could not be separated.

The operating conditions and design installation can be separated in test rigs using the occurrence manifestation characteristics for this corrosion process as a measure for the likelihood of corrosion. After an induction period of 200 days the corrosion is most often found under intermittent and stagnant conditions in the test rigs. Furthermore, a seasonal influence can be observed. It was shown in experiments performed in the laboratory that it should be possible to considerably minimize this induction period found in the test rigs.
An Evaluation of Countermeasures to Microbiologically Influenced Corrosion (MIC) in Copper Potable Water Supplies
Authors: Fischer WR , Wagner DHJ , Paradies HH
Published: March 2009

Unexpected pitting of copper pipes in drinking water installations has appeared mainly in public buildings (often in hospitals) at a small number of places around the world (for example, Germany, Scotland, Saudi-Arabia). Experience and scientific based knowledge about pitting corrosion of copper does not indicate a remarkable susceptibility in the respective drinking water installations. Because substances of biological origin were mixed with the solid corrosion products, the following hypothesis was generally accepted: microbiologically influenced corrosion (MIC).

Though the mechanism of MIC is by no means clear in detail, promising countermeasures have to be developed, substantiated and introduced into practice to protect existing installations. In this paper, the arguments for qualified actions are described and, when available, the success of these measures are mentioned. It can be stated that the likelihood of MIC in copper can be reduced to technically acceptable or even to negligible values by a combination of some well-known methods of corrosion protection.
Concepts Behind ASTM E 931-85: Empirical Practice for Classification of Occupancies for Their Relative Fire Hazard to Life
Authors: Hirschler MM
Published: March 2009

After the ASTM fire policy was first adopted in 1973, it was established that committee E5 would be responsible for developing fire hazard assessment and fire risk as- sessment standards. Since fire hazard is directly related to the type of occupancy involved, it was quickly recognized that a practice needed to use different criteria depending on the occupancy. Thus, a set of 23 occupancies was developed. The associated hazards were weighted based on empirical hazard ratings associated with issues such as (1) presence or absence of detection or suppression systems or both; (2) factors based on the fire, the occupants, or the type of ignition; and (3) the area available per occupant. A modified Delphi approach was used, based on ASTM committee members, to develop the numerical output. The result was a standard practice originally entitled “Assessment of Fire Risk by Occupancy Classification,” which was published as ASTM E 931, in 1985.

This standard was generated well before proper techniques existed to carry out fire hazard or fire risk assessments. The technology of fire hazard and fire risk assessment has since become more quantitative, and subjective assessments now have insufficient validity. ASTM E5 has also now developed a standard guide for development of fire hazard assessment stan- dards, ASTM E 1546. The definitions of fire hazard and fire risk used by the fire science community have been improved, so that the real focus of the standard was discovered to have been fire hazard, rather than fire risk. Finally, it was discovered that there had been some transcription errors between the values calculated for ASTM E 931 and those actually printed in the standard. An attempt was made to correct the mislabeling (by replacing fire hazard for fire risk) to include the corrected tables and figures and thus develop a modified standard. This was rejected in June 1992 by ASTM subcommittee E5.15, even as an interim measure. A new standard practice, bearing the number ASTM E 931 and entitled “Classification of Occupancies for Their Relative Fire Hazard” will soon be published excluding all numerical values.

Building codes and insurance companies often use occupancy classifications in order to compare the different threats to life or property inherent in the occupancy itself. Such codes control the use of materials, products, or assemblies in buildings. However, they often do not specifically address the potential threat posed by those furnishings or contents brought in by the consumer. The empirical practice described contains guidelines for rating the response of occupancies to a fire on the basis of the predicted threat to life. Thus, this paper was written to aid such potential users by ensuring ASTM archival maintenance of the correct results of the original work, which has had wide empirical use, rather than because the numbers have rigorous validity.
Using California Technical Bulletin 133 to Measure Heat Release Rate Tests of Seating Furniture
Authors: Damant GH , Nurbakhsh S
Published: March 2009

California Technical Bulletin 133 is a fire test for seating furniture manufactured for use in public buildings. The test criteria of TB 133 have been modified to require mea- surement of peak rate of heat release and total heat release in the first 10 min of the test. This paper has summarized the history of TB 133, the test protocol, and test data from several hundred product evaluations. In addition, the effect of fire blocking materials, upholstery fabrics, filling or stuffing materials, and furniture style on heat release and other test criteria is discussed.
Quantitative Large-Scale Tests of Furnishings in Europe
Authors: Sundström BE
Published: March 2009

In Europe, the harmonization of fire testing of upholstered furniture burning behavior is expected to be based on modern test technology. One approach is to define a design fire scenario of special importance and seek test methods that can predict fire conditions. Such a scenario is a room where a piece of upholstered furniture is on fire. That scenario is defined in the draft furniture directive by the Commission of the European Communities (CEC). The draft directive says that the atmosphere in such a room must remain for a reasonable period of time after ignition such that it does not endanger the lives or physical well being of exposed persons. This will be achieved by controlling the rates of heat release, smoke, and toxic gas production. The only test methods that measure these parameters are, for example, oxygen consumption calorimeters, the cone calorimeter, and the furniture calorimeter. The furniture calorimeter is a test method for full-sized items. The test output is useful for predicting the design scenario fire conditions. However, because it is large scale it becomes too expensive for routine testing of large quantities of furniture. A small-scale test is required that can model the large-scale furniture calorimeter output. The candidate test is the cone calorimeter.
Consumer Protection from Home Drapery and Drapery Liner Flammability
Authors: Nelson CN , Burns DJ
Published: March 2009

Despite a perception that consumers know by education, experience, or even common sense that textile products will burn, the NFPA data on incidents in which curtains and draperies fueled dwelling fires disproves this belief. This study addresses the potential for increased fire risk from draperies in combination with separate drapery linings. The results raise the question of how best to protect the consumer from unnecessary fire risk with home draperies and drapery liners.
1983 to 1990 Fire Losses in Ontario: A Focus on Furnishings and Contents of Buildings as Ignition Sources and Items to First Ignite in Fires
Authors: Crawford D , Prencipe M
Published: March 2009

Fire loss statistics play a vital role in the identification of fire loss trends; in the legislative and standard development process; and in promoting the reduction of loss of life and property from fire. To fulfill the need for fire loss data, the Office of the Ontario Fire Marshal has been recording detailed information on all fires occurring in the province since 1983.

This study consists of an analysis of fire losses occurring in Ontario from 1983 to 1990 and focuses on furnishings and building contents as both ignition sources and as items to first ignite in fires. Property types targeted fall within a broad range of categories including places of assembly, institutional facilities, commercial establishments, and warehousing facilities; however, more emphasis is placed on residential properties which account for close to 70% of all structural fires and over 90% of all structural fire deaths. To better define the circumstances surrounding given incidents, some fires identified by object first ignited are further broken down by ignition source. In addition, several fire death scenarios are constructed for residential properties.

Findings reveal fire losses that could potentially be altered through public education, regulation, and the enhancement of fire and flammability properties of furnishings and building contents.
Critical Analysis of the OSU Room Fire Model for Simulating Corner Fires
Authors: Janssens ML
Published: March 2009

The OSU Room Fire Model was developed by Professor Smith and several graduate students at Ohio State University between 1980 and 1987. It is one of the few models available allowing for the prediction of the contribution by wall and ceiling linings to compartment fire growth. The scenario being considered is that of a fire in a single room with a single ventilation opening. Several walls or the ceiling are covered with a combustible lining material that is exposed to a (gas burner) ignition source. Flame spread over and heat and smoke release from the lining is obtained as a function of time on the basis of calculated thermal exposure in the room and ignition, flame spread and release rate properties of the lining measured in a bench-scale test, that is, the ASTM E 906 heat release calorimeter. The poor structure of the FORTRAN source code and the lack of comprehensive documentation make it very difficult to understand the physical basis for the model. To evaluate the accuracy of the model and identify areas where the underlying physics can be improved, a modified version of the model was developed as part of a joint research program between the American Forest & Paper Association (formerly the National Forest Products Association) and the USDA Forest Products Laboratory. This paper gives an overview of the physical basis for the original OSU room fire model and describes the modified model named MOSURF (Modified OSU Room Fire). The modifications in MOSURF include conversion of the computer code to BASIC, use of SI units instead of British units, restriction to the corner configuration with a noncombustible ceiling, input data from the Cone Calorimeter (ASTM E 1354), and LIFT apparatus (ASTM E 1321), and some changes to the physics and numerical solution procedures.
Fire Properties of Room Lining Materials Measured by the Cone Calorimeter, OSU, IMO, and Full-Scale Room/Corner Tests
Authors: Kim A
Published: March 2009

Thirteen typical construction materials were evaluated over a two-year period using three small-scale standard test methods; the ASTM E 906 method using the Ohio State University Calorimeter (OSU), the International Maritime Organization (IMO) test method using the Robertson (radiant panel) apparatus, and the ASTM E 1354 method using the Cone Calorimeter. The same lining materials were also evaluated in full-scale room burn tests.

Small-scale test data were compared with those of full-scale tests. Each small-scale test method was examined to evaluate its appropriateness for predicting full-scale fire performance of lining materials. The cone calorimeter and OSU methods were also evaluated to determine repeatability and reproducibility.

The data from all tests were examined to determine patterns of correlation between the small-scale and full-scale results. Based on the data provided by the OSU and the IMO methods, it seems possible to classify materials that flashover in the full-scale room burn using the PHR and THR from the small-scale tests. Materials with PHR values above 220 kW/m2 and THR values above 45 MJ/m2 in the OSU test (with 50 kW/m2 exposure) will likely reach flashover in the selected room fire scenario.

Cone calorimeter data were used to approximate flashover time in the full-scale test. Various combinations of sample density, thickness, ignition time, PHR, and THR were used to predict flashover time. The goal was not to correlate flashover times necessarily, which may depend on the ignition flame size, but to determine the fire hazard potential of materials by determining whether the material will flashover in a full-scale test. The small-scale methods were not always adequate in predicting full-scale performance for some materials, such as rigid polyurethane.
Emission of Volatile Organic Compounds from a Vinyl Floor Covering
Authors: Clausen PA , Laursen B , Wolkoff P , Rasmusen E , Nielsen PA
Published: March 2009

The emission of volatile organic compounds (VOCs) from a vinyl floor covering has been evaluated in two small climatic chambers and a microchamber using different air exchange rates and loading factors. The concentration versus time emission curves for cyclohexanone and phenol were decreasing. Evaluation of the emission data showed that a first order decay model was insufficient to describe the emission adequately. However, in spite of the different air exchange rates and chamber concentrations, the first order rate constant could be reproduced when the model was fitted to simultaneous measurements in the three chambers. This indicated that the emission was controlled by internal diffusion. A simplified model for emission controlled by internal diffusion in the source was developed, applying a diffusion coefficient which depends exponentially on the concentration in the source. This model described the emission curves satisfactorily. However, the model parameters were not reproducible, probably because the samples were inhomogeneous with respect to VOC content and effective thickness. All results indicated that the concentrations of cyclohexanone and phenol were almost homogeneous at test start (because of the wrapping of the samples during storage prior to testing) and that the emission after a short initial period became controlled by internal diffusion in the source.
Simple Modeling to Determine Appropriate Operating Conditions for Emission Testing in Small Chambers
Authors: Girman JR
Published: March 2009

Much of the mass-balance modeling of concentrations produced by indoor sources has been based upon emission rates obtained from small chamber testing. The suitability of emission rates used as inputs to such models is important and can depend upon the operating conditions of small test chambers. However, these operating conditions to date have largely been established on the basis of intuitive choices, that is, what appears reasonable in simulating actual full-scale indoor environments, rather than a critical examination of factors that can affect emissions. In this paper, the consequences of these choices are examined, and this examination suggests that air in chambers, as currently operated, may be stagnant. This indicates the need to measure air velocities under current operating conditions. Suggestions for improving chamber operating conditions are presented that may produce more accurate emission rates.
Modeling of Indoor Air Quality for a Personal Computer
Authors: Yamamoto T , Ensor DS , Sparks LE
Published: March 2009

A menu-driven ventilation model for a personal computer was developed that is capable of determining the distributions of time-averaged, two-dimensional, steady-state flow fields and particulate or gaseous contaminants under isothermal conditions for a given particulate/gaseous diffusion coefficient. The model was written for a personal computer so that engineers can use it as a tool to evaluate a potential ventilation performance in indoor space yet to be designed.

The model's computational speed is extremely fast (a few minutes) with reasonable accuracy. This paper discusses the computational algorithm and user interactiveness for the use of this model. Case studies were performed for a simple indoor environment. Ventilation effectiveness in relation to the locations of the supply air duct and the contaminant source was investigated.
Theoretical Evaluation of Impact of return Air and Thermal Load on Air Quality in a Multizone Building
Authors: Klobut K
Published: March 2009

The computer programs published so far enabled the computation of airflows assuming constant temperatures or the calculation of air temperatures assuming constant airflows. Recently, a new microcomputer program was developed in which thermal conditions were considered when predicting the spread of contaminants in buildings. The program enabled simultaneous dynamic simulations of contaminant distribution, airflows, and temperatures in a multizone building. Using the new program, the dynamic distributions of contaminant concentration and air quality in an example building were determined with and without the recirculation of ventilation air, with different thermal loads and with several door positions. For comparison, some simulations were repeated in isothermal conditions. The results showed that a high thermal load increased the spread of contaminant. Recirculation of the ventilation air had a deteriorative impact on the air quality in the simulated building. There was a clear difference in the air qualities predicted by the respective simulations carried out with and without thermal analysis. It is believed that the inclusion of thermal analysis considerably improved the calculation method for the evalution of contaminant distribution in a building.
The Practical Application of Indoor Airflow Modeling
Authors: Jones P , Waters R
Published: March 2009

This paper discusses the application of three-dimensional computational airflow and smoke modeling to building environmental design. It is particularly concerned with the integration of modeling into the design process. The principles of airflow and smoke modeling techniques are discussed in terms of: • definition of building geometry and boundary conditions, • skills and resources required to carry out modeling, and • visualization of results.

The integration of modeling into the design process can be applied at two levels: • to assist in the development of design solutions at the early concept design stage and • to assess the design at detailed design stage.

During both stages, close liaison with the design team is essential. It is also necessary to be able to carry out the modeling work in “design time.” Results should be of a good visual quality in order to be easily understood by the design team and the client. This paper relates to a range of design projects. In each project, the use of modeling has had a significant impact on the design solution. This paper concludes that computational airflow modeling, if carried out by skilled personnel, can reduce the risk of building failure due to unsatisfactory environmental performance.