The absorption cross sections of nitric acid have been measured in the 1100-1900 Å region. The process HONO,h OH(2)+NO2 occurs below 1475 Å, much shorter than the thermochemical threshold at 2040 Å. The OH(Σ) fluorescence yield is less than 2%. The vibrational and rotational distributions of OH(E) from HONO2 photolysis at 1236 Å have been measured and compared with those from H2O and H2O2 photolysis. The excess energy beyond that required to dissociate the molecule and to excite ground state OH to OH(22) is converted to rotation and much less to vibration of OH(2E) in contrast with linear cyanogen molecules where the excess energy appears as vibration and much less as rotation of a CN product. The results of internal energy partitioning have been compared with calculations based on a simple quasidiatomic impulsive model. The deviation from the model is attributed to either a process involving a large change in bond angle or in bond length. The rotational distributions of OH(E) at v'=0 show a narrow peak at N'=20 for H2O photolysis and a broad peak at N'10 for HONO, photolysis both at 1236 Å. The extent of rotational excitation is expressed in terms of an impact parameter. The large impact parameter is found for H2O and H2O, photolysis while for HONO2 photolysis the impact parameter is small. The rotational distributions of OH(22) from H2O and H2O2 photolysis at 1236 Å deviate completely from Boltzmann behavior while that from HONO, approaches the Boltzmann distribution. The process to yield the electronically excited NO2 from HONO, photolysis at 1236 Å is less than 0.5%.

20088. Todd, T. R.; Olson, W. B. The infrared spectra of 12C32S, 12C34, 13C32S, and 12C3S, J. Mol. Spectrosc. 74, 190-202 (1979).

Key words: carbon sulfur; diode laser; free radical; infrared absorption; vibration-rotation spectra.

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Using a tunable diode laser spectrometer, the infrared absorption spectra of four isotopic species of carbon monosulfide have been observed in the positive column of a dc discharge of CS2 and Ar. The wavenumbers of 115 vibration-rotation transitions between 1180.5 and 1266.1 cm have been measured. These lines were assigned to the 1-0, 2-1, 3-2, and 4-3 bands of 12C32S, the 1-0 and 2-1 bands of 12C34S and 13C32S, and the 1-0 band of 2C33S. These new data have been combined with the previous infrared and microwave results to determine Dunham coefficients (Y), the Dunham potential expansion constants (ao,a,a,a,, and a1), and the classical turning points by the RKR method.

20095. Akins, D. L.; King, D. S.; Stephenson, J. C. Vibrational relaxation of à CF2 (v2=1–6) in non-reactive collisions, Chem. Phys. Lett. 65, No. 2, 257-260 (Aug. 15, 1979).

Key words: energy transfer; laser excited fluorescence; multiphoton dissociation; vibrational relaxation.

Rate constants have been measured for collisional energy transfer as a function of vibrational quantum number in the first excited singlet state of the CF2 radical. Total vibrational deactivation rates at T=295 K are reported for the bending mode, à CF, (2′′), for 1<n<6 in collisions with He, Ne, N2 and SF, which do not electronically quench the à CF2. The predominant pathway of vibrational deactivation is the singlequantum change A CF2 (2′′)+M→à CF2 (2′′1)+M+AE=494 m'. However, as n increases, rates for two- and three-quantum changes become increasingly important. These results are generally consistent with the principles of vibrational energy transfer found previously for ground electronic state molecules.

cm

20099. Hougen, J. T. Double group considerations, Jahn-Teller induced rovibronic effects, and the nuclear spin-electron spin hyperfine Hamiltonian for a molecule of symmetry C3, in an electronic 'E state, J. Mol. Spectrosc. 81, 73-92 (1980).

Key words: degenerate electronic state; double groups; Hamiltonian; hyperfine; Jahn-Teller effect; methoxy; rotational levels.

Two different double groups of the point group C, are compared. These double groups arise for molecules in a 'E state, and are associated with the half-integral electron spin, and with a half-integral vibronic quantum number, respectively. For many aspects of molecular energy level calculations, the use of these double groups can be avoided if desired. Contributions to the effective rotational Hamiltonian for a C1, molecule in a 1E electronic state are derived. These contributions correspond to large "l-type doubling" and "(2, -1) resonance" terms, and arise because of the Jahn-Teller distortion tendencies of the molecule. Similar contributions to the effective rotational Hamiltonian, which arise from interactions with other electronic states, are also briefly considered. A hyperfine Hamiltonian is derived, which describes the interaction of the three proton nuclear spins in a C1, molecule of the type CH,O with the odd electron spin in a E electronic state. A prescription for determining hyperfine matrix elements in a Hund's case (a) basis set is given.

20102. Krauss, M.; Stevens, W. J.; Neumann, D. B. The dispersion damping functions and interaction energy curves for Xe-Xe, Chem. Phys. Lett. 71, No. 3, 500-502 (May 1, 1980).

Key words: dipole; dispersion; interaction energy; octupole; polarizabilities; quadrupole; Xe-Xe.

Ab initio potential energy curves have been calculated for the ground state of Xe, including dispersion interactions. The total interaction energy has been approximated by a sum of the repulsive Hartree-Fock interaction plus the attractive dispersion interaction which is appropriately damped to take account of charge overlap.

20105. Faulkner, D. J.; Freeman, K. C. Gas in globular clusters. I. Time-independent flow models, Astrophys. J. 211, No. 1, 77-90 (Jan. 1, 1977).

Key words: globular clusters; hydrodynamics; interstellar matter; mass loss, stars; radiation radio sources; 21-cm.

A search for Ha emission in five globular clusters has yielded upper-limit ionized hydrogen masses within the core radii of MH+<0.1-0.7 M.. This augments the findings of previous searches for ionized hydrogen (both radio and optical) that clusters are gas deficient with respect to the mass loss predictions of evolutionary theory, if the gas remains in the cluster.

Time-independent gas flow models have been constructed for globular clusters of 105 M. and 106 M., with physical assumptions chosen to maximize the predicted gas content. Ionization by electron impact was assumed, and the ionization state of both hydrogen and helium was calculated throughout the flow; the radiative cooling of the gas under these conditions was treated with considerable care. For the 103 M。 cluster, steady-state flows were obtained for all gas input energies, B, down to (2ẞ)12 = 17 km s1, and it seems certain that gas outflow will occur for all plausible stellar mass loss mechanisms. For the 10° M. cluster, radiative cooling prevented gas outflows for input energies less than (2B)/2 <120 km s', and it appears that red-giant-branch mass loss will result in the gradual

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accumulation of gas. Integrated surface brightness and flux values for the flow models showed no clear conflict with the presently observed

upper limits for the 21 cm line, the radio free-free, and Ha. In the 21 cm line case, however, the observations are on the threshold of the predicted emission for 10 M. cluster flow models with no photoionization and with very low gas ejection energy, and further attempts to detect neutral hydrogen seem well worthwhile.

20108. Chanmugam, G. Cyclotron absorption in accreting magnetic white dwarfs, Astrophys. J. 241, No. 3, 1122-1130 (Nov. 1, 1980).

Key words: binary stars; magnetic stars; ultraviolet sources; white dwarfs.

The cyclotron absorption coefficient is calculated using a three-dimensional Maxwellian distribution for the electrons for a wide range of temperatures and frequencies. Numerical fits of the form a(w, 0)=exp[-(a+a,n2+a,n)], where n=[(π/2)−0] are presented and compared with previous results, whose range of validity is clarified. The results are applied to a plasma slab which is perpendicular to the magnetic field, and it is shown that there are deviations from the Rayleigh-Jeans spectrum predicted in earlier works. Comparison with observations for AM Herculis suggests that its magnetic field is about 5× 10' gauss (or less). 20110. Reader, J.; Luther, G.; Acquista, N. Revised 6p 2P/2 level of Mo XIV, J. Opt. Soc. Am. 71, No. 2, p. 204 (Feb. 1981).

Key words: ionized; molybdenum; spectrum; ultraviolet; vacuum; wavelengths.

New observations of the 4s-6p transitions of Mo XIV have led to a revised identification for the 4d 2D3/2-6p 2P1/2 transition and a revised value for the 6p 2P1/2 level.

20111. Maki, A. G.; Lovas, F. J. The infrared spectrum of "PN near 1300 cm', J. Mol. Spectrosc. 85, 368-374 (1981).

Key words: diode laser; high temperature; infrared spectrum; molecular constants; phosphorus nitride; rotationvibration spectrum.

The infrared absorption spectrum of the PN molecule has been measured at temperatures between 800 and 1050°C with a tunable diode laser. The transitions measured ranged from J′′ = 3 to J" = 53 and included the vibrational transitions v=1←0, 2←1, 3. 2, and 4-3. These measurements are combined with microwave measurements made by others to yield a consistent set of ten Dunham ro-vibrational constants and their

uncertainties.

20113. Linsky, J. L. Theory of stellar coronae: An interpretation of x-ray emission from non-degenerate stellar sources, (Proc. HEAD/AAS, Cambridge, MA, Jan. 28-30, 1980), Paper in Cool Stars, Stellar Systems, and the Sun, A. K. Dupree, ed., pp. 217-235 (Smithsonian Institute, Cambridge, MA, 1980).

Key words: stars, coronae; stars, winds; x rays, sources.

I present arguments to demonstrate that the acoustic wave heating theory of stellar coronae is inadequate to explain Einstein observations of stellar coronae as well as previous ultraviolet and X-ray observations of the Sun and other stars. I outline the various lines of evidence that imply that magnetic fields, stellar rotation rates, and to some extent convection zone parameters are the important quantities in determining coronal heating and thus X-ray emission. These general results and the recent Einstein Observatory stellar observations suggest a speculative scenario of stellar coronae which is described in detail.

20114. Nesbitt, D. J.; Leone, S. R. Br*(P, )+H2(v=0,1): Laser studies of the competition between reactive pathways and inelastic energy transfer channels, J. Chem. Phys. 73, No. 12, 6182-6190 (Dec. 15, 1980).

Key words: electronic excitation; excited states; laser, reaction dynamics; spin-orbit; vibrational excitation.

A systematic experimental study has been made on inelastic and reactive processes in the Br*(2P12)+H2(v=0,1) system. Laser photolysis and time-resolved infrared detection techniques allow direct observation of the previously unreported E-V equilibrium: Br*+H2(v=0)—Br+H2(v=1). A nonlinear kinetic analysis is presented that permits an estimate of the quantum efficiencies for the forward and reverse E-V processes, and provides an explanation for previous discrepancies in measured total Br* quenching rates with H2. In this work the quenching rate constant for Br* by H2 is determined at very low Br concentrations to be 6.3(+1)× 10-12 cm3 molecule1 sec1. At higher concentrations of Br*, second order processes involving collisions of Br* with H,(v=1) have been investigated. A substantial fraction of the Br*+H2(v=1) collisions react to form HBr(v=0)+H(S2). It is suggested that the resonant E-V transfer pathway in the entrance channel Br*+H2(v=1)→→Br+ H2(v=2) may provide an efficient mechanism for potential surface crossing thereby enhancing the reaction probability. 20115. Hougen, J. T.; Oka, T. Vibrationally induced nuclear quadrupole coupling in tetrahedral and octahedral molecules, J. Chem. Phys. 74, No. 3, 1830-1839 (Feb. 1, 1981).

Key words: degenerate vibrational effects; hyperfine energy levels; hyperfine Hamiltonian; quadrupole coupling theory; spherical top molecules; tetrahedral and octahedral molecules.

Hyperfine splittings arising from the presence of a quadrupolar nucleus at the center of a molecule belonging to the point group Ta or On (e.g., 189OsO or 235UF) are symmetry forbidden to a high degree of approximation. Nevertheless, quadrupole splittings can be induced by either vibrational or rotational distortions of the molecule, i.e., by distortions similar to those responsible for inducing electric dipole moments in T molecules. Such hyperfine splittings have recently been observed in several laboratories using laser saturation spectroscopy. In this paper we investigate theoretically the quadrupole splittings induced by excitation of doubly and triply degenerate vibrations in T, and O molecules. We find that much of the vibration-rotation formalism already present in the methane literature can be applied with only minor changes to the induced-quadrupolecoupling problem, and that rather simple theoretical relationships can be derived between the quadrupole splitting and the tetrahedral or octahedral vibration-rotation splitting of a given level. Values for the scalar and tensor contribution to the quadrupole coupling constant have been derived from the experimental data for 189OSO, reported by Bordé et al.

20123. Parr, A. C.; Ederer, D. L.; Cole, B. E.; West, J. B.; Stockbauer, R.; Codling, K.; Dehmer, J. L. Triply-differential photoelectron studies of molecular autoionization profiles: The 710-730 Å region of the N, spectrum, Phys. Rev. Lett. 46, No. 1, 22-25 (Jan. 5, 1981).

Key words: autoionization; Franck-Condon factors; ionization; nitrogen; Nz; photoelectron spectra; photoionization; synchrotron radiation; vibrational intensity distribution.

Photoelectron studies of molecular autoionization resolved into position within the resonance profile, photoelectron ejection angle, and final vibrational state are reported. By using the first members of prominent window and absorption series converging to N, BE as an example, striking variations of vibrational branching ratios and photoelectron asymmetry parameters within autoionizing profiles are demonstrated. Such triply differential data represent a very detailed characterization of the rovibronic interactions governing molecular autioionization.

20124. Haisch, B. M.; Linsky, J. L.; Harnden, F. R., Jr.; Rosner,

R.; Seward, F. D.; Vaiana, G. S. Einstein x-ray observations of
Proxima Centauri and the surrounding region, Astrophys. J. 242,
No. 2, L99-L103 (Dec. 1, 1980).

Key words: flare stars; stars, individual; stellar coronae;
X-ray sources; x rays, variable.

We report the first detection of both quiescent and flaring soft X-ray emission from a dMe flare star, Proxima Centauri (dM5e). The data are analyzed for temporal variability and spectral characteristics. The quiescent state is characterized by a mean X-ray luminosity of ~1.5× 1027 ergs s', corresponding to a mean surface flux of ~7x10 ergs cm s', and an inferred temperature of ~4× 10° K. The flare we have detected has a peak flux of ~7.4 × 1027 ergs s* and a peak temperature of ~ 17x10° K. We discuss implications of these data for models of the quiescent and flare coronae of dMe stars.

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20125. Shy, J. T.; Farley, J. W.; Lamb, W. E., Jr.; Wing, W. H. Observation of the infrared spectrum of the triatomic deuterium molecular ion D3*, Phys. Rev. Lett. 45, No. 7, 535-536 (Aug. 18, 1980).

Key words: infrared spectra; vibrational-rotational spectrum of D,*.

The infrared vibrational-rotational spectrum of the D3+ isotope of the simplest polyatomic molecule is observed. Eight intervals between 1750 and 1850 cm have been measured to an error of 0.0005 cm ̄1 or 0.3 ppm (at 70% confidence level). Four have been identified as members of the fundamental degenerate vibrational band. The rest apparently involve unidentified higher vibrational-rotational levels.

20133. Birnbaum, G.; Sutter, H. Collision-induced absorption in a highly symmetric molecule-SF, Mol. Phys. 42, No. 1, 21-32 (1981).

Key words: band shape; collision induced absorption; hexadecapolar moment; liquid spectra; SF6.

The far-infrared absorption spectra of gaseous (298 K) and liquid (273 K, 233 K) SF, obtained by Rosenberg and Birnbaum are analysed in terms of recent theoretical developments. Analysis of the band shape in the gas and liquid phases indicates that hexadecapole-induced absorption accounts only for the low frequency portion of the collision-induced band. The major part of the absorption can be attributed to a much shorter range mechanism such as anisotropic overlap. The resulting induced dipole which varies very rapidly with intermolecular separation and is consistent with a (7-28) interaction energy gives a good description of the liquid spectra. Collision-induced absorption and depolarized light scattering in SF, are compared. From a decomposition of the collision-induced gaseous spectrum, the value of the hexadecapolar energy, 2/σ, is 2.7× 10-24 J (0.20 K) which yields a value of the hexadecapole moment, Þ, of 18x 10-60 Cm for σ=0.468 nm.

Building Technology

BSS132. Yokel, F. Y.; Yancey, C. W. C.; Mullen, C. L. A study of reaction forces on mobile home foundations caused by wind and flood loads. Nat. Bur. Stand. (U.S.) Bldg. Sci. Ser. 132; 1981 March. 84 p. SN003-003-02301-9, $4.00.

Key words: buoyancy forces; flood forces; foundations; hurricane forces; mobile home; soil anchors; standards; tiedown; wind forces.

Forces acting on the foundations of mobile homes subjected to wind and flood loads were calculated and are presented in a

series of computer-generated charts. The loading conditions considered are the two levels of wind loads presently stipulated in the Federal Mobile Home Construction and Safety Standard, a hurricane windload recommended by the National Bureau of Standards (NBSIR 77-1289), buoyancy forces, and draft forces resulting from flood water flow. The calculated forces are compared with present anchoring requirements in ANSI Standard 119.3 (NFPA No. 501 A). It is concluded that diagonal ties are instrumental in resisting wind forces, and that vertical ties are more effective than diagonal ties in resisting flood forces. TN1135. Rossiter, W. J., Jr.; Mathey, R. G.; Busching, H. W.; Cullen, W. C. Cooling of bitumen during construction of builtup roofing systems-A mathematical model. Nat. Bur. Stand. (U.S.) Tech. Note 1135; 1981 March. 76 p. SN003-003-02302-7, $4.00.

Key words: bitumen application temperatures; bituminous roofing; built-up roofing; cooling of roofing bitumens; mathematical model; roofing.

Construction of bituminous built-up roofing systems in the United States generally involves the application of hot bitumen to the roofing components, including deck, insulation, and felts, to adhere them to each other and to form a waterproof membrane. Adequate adhesion of the bitumen to the roofing component materials may be obtained only when the hot bitumen is applied at a viscosity sufficient to flow uniformly, to cover the component surfaces or substrate completely, and to provide the proper thickness. During construction, rapid cooling of hot bitumen increases its viscosity significantly. If the viscosity becomes too high, poor adhesion between components, voids within the bitumen, and an excessive and non-uniform thickness of the bitumen may result.

This report describes a mathematical model based on finitedifference equations for calculating transient heat flow to estimate the cooling time of hot roofing bitumen. Estimates of the time required for hot bitumen to cool from its application temperature to 300°F (149°C) were computed as a function of material and environmental factors including: quantity of applied bitumen, bitumen application or contact temperature, air temperature, wind speed, and thermal properties of the bitumen and of the roofing components. The model was used to predict cooling times expected for hot asphalt applied to typical substrates with thermal properties representative of those of polyurethane foam and glass fiber insulation boards, insulating concrete, plywood, concrete, and steel decks, and roofing felt on decks or insulations. In addition, the model was used to predict cooling times for hot coal tar pitch applied to concrete and to felt adhered to glass fiber insulation. The results of the calculations demonstrate the widely-varying bitumen cooling times which depend upon the component material to which the bitumen is applied and the environmental conditions during application. Under certain environmental conditions, hot bitumen applied to some substrates cools extremely rapidly. In these cases, sufficient time for proper application may not be available.

NBSIR 80-2081. Cooke, P. W. Comparison of selected codes and standards relating to existing residential buildings. 1980 July. 310 p. Available from: NTIS; PB 81-120842, $17.00.

Key words: building rehabilitation; codes; comparative analysis; existing buildings; housing codes; maintenance; model codes; occupancy; performance levels; regulation; standards.

The performance levels of older residential buildings generally do not comply with the standards for safety or function that are required of new buildings. This report presents a comparative analysis of the specific provisions contained in seven codified

documents that have been promulgated to regulate the health and safety aspects of existing residential buildings. The study examines and presents information on: (1) The extent to which codes vary among each other in establishing minimum requirements for life, health and safety in existing dwellings. (2) The differing approaches provided by traditional housing codes in contrast to more recently developed rehabilitation guideline documents regarding performance levels. (3) The degree to which each code meets its intended goals of providing and maintaining human shelter, protection, and privacy. The code provisions are compared and analyzed in sixteen major code areas (e.g., structural requirements, light and illumination, plumbing requirements, etc.). Various inconsistencies among code documents with respect to uniformity and irrational approaches in the historical development of code provisions are indicated.

NBSIR 80-2111-1. Ellingwood, B. R. Review and refinement of ATC 3-06 tentative seismic provisions. Report of technical committee 1: Seismic risk maps. 1980 October. 30 p. Available from: NTIS; PB 81-187551, $6.50.

Key words: buildings; buildings (codes); buildings (design); earthquake; seismic risk maps; standards; structural engineering.

The Tentative Provisions for the Development of Seismic Regulations for Buildings were developed by the Applied Technology Council to present, in one comprehensive document, current state-of-knowledge pertaining to seismic engineering of buildings. The Tentative Provisions are in the process of being assessed by the building community. This report is one of a series of reports that documents the deliberations of a group of professionals jointly selected by the Building Seismic Safety Council and the National Bureau of Standards and charged with reviewing the Tentative Provisions prior to the conduct of trial designs. The report contains the recommendations and records of the committee charged with review of the seismic risk maps. The committee made 4 recommendations for revisions to the Tentative Provisions. These recommendations were made to the parent group, the Joint Committee on Review and Refinement, and their action on these recommendations is documented in a companion report. NBSIR 80-2111-3. Salomone, L. A. Review and refinement of ATC 3-06 tentative seismic provisions. Report of technical committee 3: Foundations. 1980 October. 57 p. Available from: NTIS; PB 81-187569, $8.00.

Key words: buildings; design; earthquakes; engineering; foundations; professional practice; provisions; soil structure interaction; standards.

The Tentative Provisions for the Development of Seismic Regulations for Buildings were developed by the Applied Technology Council to present, in one comprehensive document, current state-of-knowledge pertaining to seismic engineering of buildings. The Tentative Provisions are in the process of being assessed by the building community. This report is one of a series of reports that documents the deliberations of a group of professionals jointly selected by the Building Seismic Safety Council and the National Bureau of Standards and charged with reviewing the Tentative Provisions prior to conducting trial designs.

This report documents the activities of Technical Committee 3: Foundations. Other committee reports are similarly available. The task of Technical Committee 3 was to review and refine Chapter 6, Soil-Structure Interaction and Chapter 7, Foundation Design Requirements in the ATC report (NBS SP-510) entitled, "Tentative Provisions for the Development of Seismic Regulations for Buildings." Two meetings were held. The opening meeting of the group was on December 11, 1979, and

the concluding meeting was on February 5, 1980. The minutes of these meetings and the findings/recommendations of Technical Committee 3 are presented in this report. These recommendations were made to the parent group, the Joint Committee on Review and Refinement, and their action on these recommendations is documented in a companion report.

NBSIR 80-2111-6. Lew, H. S. Review and refinement of ATC 3-06 tentative seismic provisions. Report of technical committee 6: Steel. 1980 October. 37 p. Available from: NTIS; PB 81. 187577, $6.50.

Key words: building; building codes; building design; earthquakes; engineering; standards; steel; structural engineering.

one

The Tentative Provisions for the Development of Seismic Regulations for Buildings were developed by the Applied Technology Council to present, in comprehensive document, current state-of-knowledge pertaining to seismic engineering of buildings. The Tentative Provisions are in the process of being assessed by the building community. This report is one of a series of reports that documents the deliberations of a group of professionals jointly selected by the Building Seismic Safety Council and the National Bureau of Standards and charged with reviewing the Tentative Provisions prior to the conduct of trial designs. The report contains the recommendations and records of the committee charged with review of the steel design provisions. The committee made 6 recommendations for revisions to the Tentative Provisions and three additional recommendations. These recommendations were made to the parent group, the Joint Committee on Review and Refinement, and their action on these recommendations is documented in a companion report.

NBSIR 80-2111-7. Yancey, C. W. C. Review and refinement of ATC 3-06 tentative seismic provisions. Report of technical committee 7: Wood. 1980 October. 41 p. Available from: NTIS; PB 81-187585, $6.50.

Key words: building; building codes; building design; earthquakes; engineering; standards; structural engineering; wood.

The Tentative Provisions for the Development of Seismic Regulations for Buildings were developed by the Applied Technology Council to

present, in one comprehensive document, current state-of-knowledge pertaining to seismic engineering of buildings. The Tentative Provisions are in the process of being assessed by the building community. This report is one of a series of reports that documents the deliberations of a group of professionals jointly selected by the Building Seismic Safety Council and the National Bureau of Standards and charged with reviewing the Tentative Provisions prior to the conduct of trial designs. The report contains the recommendations and records of the committee charged with review of the provisions for the design and detailing of wood structures. The committee made 14 recommendations for revision to the Tentative Provisions. These recommendations were made to the parent group, the Joint Committee on Review and Refinement, and their action on these recommendations is documented in a companion report.

NBSIR 80-2111-8. Faison, T. K. Review and refinement of ATC 3-06 tentative seismic provisions. Report of technical committee 8: Architectural, mechanical and electrical. 1980 October. 43 p. Available from: NTIS; PB 81-187593, $6.50.

Key words: architectural; electrical; elevators; mechanical; seismic coefficients.

The Tentative Provisions for the Development of Seismic Regulations for Buildings were developed by the Applied

Technology Council to present, in one comprehensive document, current state-of-knowledge pertaining to seismic engineering of buildings. The Tentative Provisions are in the process of being assessed by the building community. This report is one of a series of reports that document the deliberations of a group of professionals jointly selected by the Building Seismic Safety Council and the National Bureau of Standards and charged with reviewing the Tentative Provisions prior to the conduct of trial designs. The report contains recommendations and records of the committee charged with the review of the material related to architectural, mechanical and electrical provisions. The committee made seven general recommendations for revision and one recommendation for the addition of a new section on elevator design requirements. These recommendations by Committee 8 were made to the parent group, the Joint Committee on Review and Refinement, and their action on these recommendations is documented in a companion report.

NBSIR 80-2171. Lerchen, F. H.; Pielert, J. H.; Faison, T. K. Selected methods for condition assessment of structural, HVAC, plumbing and electrical systems in existing buildings. 1980 December. 111 p. Available from: NTIS; PB 81-186918, $11.00.

Key words: building rehabilitation; concrete; electrical; evaluation; HVAC; masonry; plumbing; steel; structural systems; test methods; wood.

This report was developed with the intent of assisting government officials, designers, builders, code officials, and others involved with making technical decisions relative to building rehabilitation to evaluate the condition of existing buildings.

The report describes evaluation methods available specifically for use with the structural materials of concrete, steel, masonry, and wood, as well as, for use with the supportive systems of heating/ventilating/air conditioning, plumbing, and electrical. Both commonly used methods and other possible (but more technically complex) laboratory methods are described for the reader. Comparative tables are provided, where possible, to aid the reader in making a quick selection of the evaluation method most appropriate for the particular parameter to be tested. Considerably more information is included in the area of structural systems than in the rest of the report because of the fact that this report supplements a previous effort to develop a technical manual on structural strength for rehabilitation of existing buildings.

NBSIR 81-2231. Yonemura, G. T. Criteria for recommending lighting levels. 1981 March. 60 p. Available from: NTIS; PB 81-185126, $8.00.

Key words: conspicuity; contrast; illumination; lighting; lighting levels; superthreshold visibility; vision.

The effect of lighting on behavior ranges from allowing simple detection of objects to creating moods and impressions. Lighting standards and recommendations for general applications should be based on the visibility (seeing) requirements where differences between individuals are minimal. Furthermore, lighting criteria or standards must evaluate the seeing process under stimulus conditions approximating those encountered in the real space. It is recommended that conspicuity, defined as: "how well the detail stands out from the background," or ease of seeing be the metric for visibility. Subjective visual response criteria cannot be universally applied where significant differences in interpretations and evaluations between individuals and/or groups of individuals occur. Instead they should be treated as design options to be applied when they are important aspects of the intended function of the space. In discussing the above issues, the paper identifies the major categories of variables included in the perception of the visual environment and

organizes them logically with respect to their relationship in developing lighting criteria and standards. This analysis includes a breakdown of the visual processes into sensory and perceptual components.

NBSIR 81-2239. Frohnsdorff, G.; Clifton, J. R. Fly ashes in cements and concretes: Technical needs and opportunities. 1981 March. 34 p. Available from: NTIS; PB 81-183428, $6.50.

Key words: cement; concrete; fly ash.

Following a brief review of the nature of fly ashes and their levels of production and use in various countries, an estimate is made of the potentially achievable level of use of fly ash in cement and concrete in the United States. The estimate assumes that 20 percent of the mass of all the portland cement used in the United States could be replaced by the same mass of fly ash; it ignores possible competition from granulated blast-furnace slag as a finely-divided mineral admixture for concrete. It appears that about 16 million tonnes (18 million tons) per year of fly ash could be consumed in cement and concrete, provided there were sufficient ash of suitable quality and a general understanding of the technical requirements for satisfactory fly ash use. Present standards which affect the use of fly ashes are discussed. Steps which could be taken to improve knowledge of factors affecting fly ash performance in cement and concrete, and hence to improve standard test methods and specifications, are outlined. NBSIR 81-2245. Adler, S. C.; Pierman, B. C. Building accessibility for the disabled: A review of research needs. 1981 March. 46 p. Available from: NTIS; PB 81-184954, $6.50.

Key words: accessibility; building accessibility; building research; fire safety; handicapped; life safety.

This report traces the evaluation of public policy on accessible environments; discusses the need for development of a research basis for the design of accessible buildings including accessibility standards for both new and existing buildings, summarizes the results and research recommendations of both the Conference on Fire Safety for the Handicapped held at NBS on November 2629, 1979 and the joint ATBCB/NBS Conference on Accessibility Guidelines held in Bethesda, Maryland on October 31-November 1, 1979, and presents an overview of current NBS accessibility research plans.

NBS-GCR-80-249. Schultz, T. J. Impact noise testing and rating1980. 1981 January. 363 p. Available from: NTIS; PB 81158610, $26.00.

Key words: acoustics; building acoustics; impact noise; noise control; noise isolation; noise rating.

A state-of-the-art review of impact noise testing and rating is presented. A historical perspective of impact noise testing and rating covers the first efforts in the 1920's through the most recent research results. The current research is discussed, with the emphasis on the development of standardized test methods and impact noise rating methods. An outline for future research needs is presented in light of the current state-of-the-art. A bibliography containing over 200 references to impact noise testing and rating is included in the report.

NBS-GCR-80-280. Achenbach, P. R. Functional performance requirements for the environmental and service systems in detached housing and their impact on building energy use. 1981 January. 168 p. Available from: NTIS; PB 81-157893, $14.00.

Key words: building energy use; building service systems; energy budgets; housing research; housing standards; performance requirements; standards development.

The energy used for the environmental and service functions of space heating and cooling, domestic water heating,