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Runoff water is an important medium transporting various types of pollution originating from the atmosphere and washed out from roofing materials. The study presents a quality assessment of runoff from different roofs in the context of trace metal concentrations. The analysed rooftops were covered with copper, tar paper and ceramic tile. The quality of the rain water collected at the same time satisfies the demands of the first grade of cleanliness according to (Journal of Laws, 2016 item1187). The highest content of copper was leached from the copper roof, containing 10.23 mg∙dm-3. In the case of zinc, the highest concentration of 15.52 mg∙dm-3 was present in the runoff from the roof covered with thermally bonded tar paper. The amount of trace metals in the ceramic roof runoff was the lowest and only for zinc slightly exceeded 1.47 mg∙dm-3 – the value determined for II class of purity. In the paper, the different levels of heavy metals leaching from different roofing materials have been confirmed.

Firebrand production from real-scale building components under well-controlled laboratory conditions was investigated. Re-entrant corner assemblies were ignited and during the combustion process, firebrands were collected to determine the size/mass distribution generated from such real-scale building components under varying wind speed. In prior work, a unique ignition methodology was developed to generate firebrands from re-entrant corner assemblies constructed of wood studs and oriented strand board (OSB). In this study, this ignition methodology was applied to re-entrant corners constructed from wood studs/OSB but fitted with actual siding treatments (tar paper and cedar siding) to determine the influence of siding treatments on firebrand generation from wall assemblies. Firebrands were collected with pans filled with water, and then the size and mass of firebrands were measured after drying. The size and mass distributions of firebrands collected in this study were compared with the data from prior component tests as well as the limited studies available in the literature on this topic. Some firebrands were found to be lighter for a given projected area than others, likely produced from cedar siding or tar paper. The effects of applied siding treatments on firebrand production are discussed in detail.

A unique experimental apparatus, known as the Firebrand Generator, was used to generate a controlled and repeatable size and mass distribution of glowing firebrands. The size and mass distribution of firebrands produced from the generator was selected to be representative of firebrands produced from burning vegetation. The vulnerability of roofing materials to firebrand attack was ascertained using fluxes of firebrands produced using this device. The experiments were performed at the Fire Research Wind Tunnel Facility (FRWTF) at the Building Research Institute (BRI) in Tsukuba, Japan. A custom mounting assembly was constructed to support full scale sections of common roofing materials inside the FRWTF. The sections constructed for testing included full roofing assemblies (base layer, tar paper, and shingles) as well as only the base layer material, such as oriented strand board (OSB). The custom mounting assembly allowed for the construction of flat roofs as well as the construction of angled roofs (valleys). Results of this study are presented and discussed.

Satellite settlements, which frequently bordered model company towns, were usually explained as havens for prostitutes, gamblers, bootleggers, and social misfits. A study of Steptoe City, Nevada, revealed more complex social and economic realities and suggested that the phenomenon was not unique to company towns. Such settlements could better be understood as special case manifestations of the shantytowns or “wrong side of the tracks” neighborhoods, which plagued most towns throughout America.

Portland cement concrete (PCC) began to be used as a surface or wearing course for pavements in the United States in the early 1900s. The joint sealant or filler materials used during this early construction period were typically sand, tar paper, coal-tar pitch, asphaltic compounds, or wooden blocks. Material specifications for these early joint filler materials were nonexistent. The main emphasis of pavement construction during this period was to "get the country out of the mud" [1], not to provide a long lasting flexible joint sealant material to protect the pavement structure. In the early 1940s, pavement engineers began to concentrate on the construction of the joints in rigid pavements and the materials used to seal those joints. It was during this time period that elastomeric materials (generally an asphalt-based material modified with crumb rubber) began to be developed for use in pavement joints and the first material specifications were developed to provide a means of quality control. As user requirements changed (i.e., materials resistant to fuel spill-age, etc.), new materials (typically polymer modified and/or extended coal-tar materials) were introduced and new material specifications were developed. New formulations have continued to be introduced with individual material specifications eventually being developed for each sealant. Typical base materials used today for pavement joint sealing include asphalt-rubber, modified coal-tar, polysulfide, polyurethane, silicone, and polychloroprene. Improvements have been made to the sealant formulations but the current material specifications have hindered innovation because they are typically material specific and generally do not directly correlate to sealant field performance. A review of the history of joint sealant material specifications, current specifications, and potential techniques that may be included in material specifications of the future to provide a more direct correlation between laboratory evaluation and field performance is presented.

Archaeological Consulting Services, Ltd. (ACS) conducted survey of 200 acres and limited testing of cultural resources on Fort McDowell Mohave-Apache Indian Community (FMIC) land at the request of Mr. Jon Czaplicki of the Bureau of Reclamation (Reclamation). The work was performed to define the boundaries of archaeological sites to be avoided by agricultural development. Eight sites were slated for preservation; however, only seven sites were relocated and flagged, and two new sites were defined. In most cases the sizes of the sites increased. This document includes lithic analyis by Ruth Rubenstein and ceramic analysis by Mac McDonnell.

During the last five years the authors have supervised 11 series of exposure tests, ranging from 6 to 25 months, of Japanese cedar samples tested in various ways to prevent attack by marine borers. Some of the new methods were applied to more than 20 ships sailing to the southern seas, but unfortunately most of them were lost or destroyed before ade_??_uate tests could be completed.Protective methods generally in use for saving wooden ships from borers are either chemical or mechanical. The chemical method kills the borers by painting or injecting preservatives or toxicants into the wood. The mechanical method prevents borers from reaching the timber by sheathing it with sheet metal or specially treated fabric. Observation of exposure tests on materials treated by these two methods have given the following results:1) Painting the exposed surface with a chemical substance harmful or disagreeable to marine borers such as copper paint, is commonly practiced as the most effective and practical method in use at present. This method is not permanent because the protective substance either gradually leaches out, or the coating itself is destroyed by abrasion in a very short time. Subsequently frequent docking and renewal are necessary.2) Sheathing the bottom with an outer board with an intervening layer of tar paper has been considered resistant, but their experiments show it quite ineffective against both shipworms and boring crustaceans over a two year period.3) Impregnating the wood with preservatives and toxicants is cons dered better than co ting, but the large amounts of impregnants necessary, and the increase of weight to the ship are undesirable.4) So far as the weight i concerned, sheathing the bottom of a ship with thin wood impregnated with creosote or copper hydroxide is better than injecting the hull itself. But the impregn ted boards lengthen the life of the ship only until the in ected tox cants leach out of the thin wood, which is usually within a year.No chemical method depending on toxicity lasts over one or two years.Next they tested various methods of applying soluble urine resin compounds, which may be so treated as to make a hard, unsoluble outside layer, giving mechanical as well as chemical protect on. Results were obtained as follows:1) Test pieces painted with urine resine compounds were not attacked by the borers after one and one half years. and after two years the test pieces were attacked slightly only at one corner where the coating abraded. The method is more effective than painting with copper.2) The two year tests of an intervening layer of urine resin compounds give complete protection against the borers. Veneer plates with two or three protective layers of urine resin compounds may be applicable for the outer protective boards of ship.3) Samples sheathed with thin boards injected with urine resin compounds lasted two years against borers.4) Another important result of this method is the waterproof quality imparted to the woodtself. The weight of samples after two years test in the sea showed only 10-20% increase remakably lower than that of the other methods which allow sometimes up to 120% increase in weight.

Case 1.— K. K., a 50 year old merchant, was examined on account of an indefinite fine vesiculoerythematous eruption which appeared on his legs and on the lower part of his thighs, an area left uncovered by his shorts and socks. The eruption caused intolerable itching, which was most pronounced during the day, especially when he was sitting. He first noticed it about the beginning of October 1939. It was apparent that this eruption had something to do with his trousers, but the exact cause remained undetermined. Wool, cleaning fluids and dyes were easily eliminated as factors. Topical application of calamine lotion containing 0.5 per cent of menthol caused amelioration of the symptoms, but recurrences of the eruption persisted until the end of December 1939, when they ceased without any determined reason. Early in October 1940 he returned presenting a similar eruption. The cause remained obscure until examination of another

A comparison was made between three types of plastic drain pipes and conventional earthen tile drains combined with cover materials of washed river sand, fibreglass, and tar paper. Rate of drawdown of a water table was measured for each combination of pipe and cover material over a period of 220 hours. Soil material that accumulated over three years in the observation pits and over four years in the pipes was measured. All combinations of pipes and cover materials provided satisfactory drainage and there were no differences of practical significance between them in terms of rate of drawdown. The river sand used in the experiment caused blockage of slot openings in corrugated plastic pipe, and one type of smooth walled plastic pipe was badly distorted by soil pressure leading to a widening of the slots, entry of soil material and breaking the fibreglass covering. Another type of plastic pipe was unsatisfactory because the perforation method left plastic material as hairs within the pipe. The fibreglass, 0.2 mm thick, was too thin to be entirely satisfactory, but was, under favourable conditions, a most effective cover material. Tar paper was quite unsatisfactory as material to prevent soil entry to pipes.