Document VKj6eEkYbmDkJRjKR749kdo0j

___ ____________ P*OOUCTDIVK**^ ;j: -' --T ' * ' ?-,Triy-~^g_,3 -iStV-*-^ ."** ^ '-"- - ~ CORRESPONDENCE* ^4683 WRG-7C PlantFHenagers All Sales Personnel From:. C. H. Wendel cc: R. M. Vlnlng H. A. Brown datr. March 28, 1973 subject: Vermicullte Fireproofing WRG 0009?. i Walt Ptckthall was asked to prepare an article on Vermicullte Fireproofing for the Western Plasterer magazine. Attached Is a copy of his article which should prove educational for all of us. Walt Ptckthall's new title Is "Doctor Of History** and he Is n< the official historian for the Pacific Region. $ CHW:me :~~ i; t. PACIFIC REGION GRACE 20185561 I 39s* " '. > ^SL VERHICULITE F lREPROOF f-Wfc'; 7r- Past and Present *r**" . 4r. v. -C^-V The old prospector poked sleepily at the remains of the previous evening's fire. He had banked it carefully and here and there tongues of flame flickered in the hot bed of coals. As the first rays of sunlight shot down from the ridge to the east his eye caught the glint of gold in the bankings he had used. His disappointment was considerable when he discovered that what at first appeared to be pea sized nuggets of the precious metal were only granules of an almost weightless\ laminated golden mineral. X- Whether this or other equally plausible stories of the discovery are the real truth is relatively unimportant but this- ' one serves well to point up the principal physical properties i of the mineral vermiculite and the industry which developed from its discovery. I^ ' The time would have been shortly after the end of World War I. The place, the Rocky Mountain area in Montana near the Canadian border- Present day maps show the site as Libby, Montana, where the townspeople will tell you with unabashed pride that they have the largest vermiculite deposit and mining operation in. the world and that the nearly seven million dollars Zonolite is presently spending on new facilities will triple the capacity 'i of the operation by 1?74. * 20185562 94683 rprospectai^ banked ftl* ToneTy firm.that n Fgl some f!fcjpfd.^ears ago the presence of the small brown mica* like flakes in the earth he used probably went unnoticed. Certainly he would have had no way of knowing that these flakes were composed of microscopically thin laminates, between which were entrapped water cells. As the flakes grew hot frpm contact with the coals the water cells turned to steam forcing the laminates to separate. At the same time oxidization was occurring and the color changed from dark brown to a highly reflective goldi The result was a granular material roughly ten times' the original..'^- . r size, impervious to fire, and an excellent insulator** Early marketing of it he new discovery concentrated' on^the i insulation field. High iresistance to fire, permanence^lightweight ; ' ' -jte- and ease of installation found ready acceptance in the marketplace. The remarkable ability to ship ore in concentrated form and expand i it at strategically locaited plants made the new product an economic success from the start. ft was World War I Ij however, that gave the fledgling business entree to the Construction Industry and the uses which are so common today. j The first major job was the Mercantile National Bank Building in Dallas, Texas. As was common practice the steel was to have been encased in Concrete for fire protection. At the last minute however the government cut the steel tonnage allocation and it was 20185563 *t - ""I'!* 7194684 mandatoryanother fire protection method be devised ta' eliminate the dead load factor of tkvhe concrete. A fire test of vermiculite-portland cement was run at the National Bureau of Standards and passed. The steel was redesigned and the project was built with the same usable space, but with only 2/3 of the steel required in the original design. The high fire resistance of the vermIcullte-portland, cement combination came to the attention of the military and with the impending threat of bombing attacks on our military Installations -V- thousands of cubic yards were poured on roofs of defense facllfttle Y. '5 y-O The Pentagon Building alone required 275 carToadsT of expande<fi^;..4.^'- vermicul ite to complete the installation- I 0 -iv' . jt- . 4 . The use of vermiculite concrete has continued to'gross and ^ today a national group of over 100 Certified Roof Deck Applicators pour an estimatedJmillion square feet of Insulating i concrete dhnually. A wide range of systems is available for I installation over structural concrete or steel decks providing i high insulation values, permanence, proper drainage and maximum ffifre resi.stance. 1 i The end of World War II was marked by an immediate revival j of the private sector of the Construction Industry. All materials were in short supply and steel was one of the most critical. If the needs of the country were to be met Architects4and Engineers- were going to have to utilize every tori to the ijiaximum. Again 20185564 vermiculite played a major role. Research and testing had continued^ and a number of assemblies had successfully passed Fire Tests at Underwriters' Laboratories. Gypsum had replaced portland cement as the binder with resulting reduction in thickness requirements and application time. The West Coast led the way in acceptance of the new concept. Two major projects in Los Angeles, the Richfield Oil Building and the Prudential Insurance Building amazed old timers in the construction field with major reductions in stee\ tonnage and completion schedule. Metal lath and vermiCulite gypsum plaster for colunns an vermicullte plaster suspended ceilings had permanently replaced the old slow cumbersome and expensive procedure of erecting wood forms around every member of the steel frame and then tediously filling each form with concrete. Metal lath and plaster fire protection continued as the standard i through the rest of the 40's and into the mid fifties. Other forces were at work however which were destined to replace the new concept by the end of that decade. In England laboratory work was being done with directly applied asbestos fiber encasement of structural steel. Reports reaching the United States indicated that the method had considerable promise. Not to be outdone by their European counterparts work was started on direct application of vermiculite. Introduction and widespread use of the piaster pump accelerated interest in the idea and in 1958 the first formulations were ready for testing. Old timers in the plastering business will recall that one of the major breakthroughs in membrane fireproofing was a vermiculite acoustical plaster ceiling. The system had passed the fire test with a 4 hour rating and gave the plastering industry its first fire rated acoustical ceiling. ,The basic formula for that acoustical plaster was modified \ and became the first vermiculite based material to pass the fi^e test for direct application on steel. j? t The new system was readily accepted by the design profession. Heating, air conditioning and lighting of major structures had become exceedingly complex and the necessity to maintain the integrity of membrane fire resistant ceilings made proper design even more difficult. The new fireproofing system,because it was directly on the steel and out of the way, provided complete flexibility and a much wider choice in finished ceilings. It was obvious too,, that the new approach was faster and more economical than metal lath and plaster. Elimination of the time and expense of lathing accounted for most of the savings. A number of West Coast buildings were fire protected with the new system during the next few years. Among the first were the Zellerbach Building in San Francisco, a California State Office Building in Oakland and ano-ther in Los Angeles. 20185566 J171 4oP~ 6* - Th* njN^material was difficult to handle in the field. Improvement in application and reduction in thickness was needed. MONO-KOT^ fi reproofing was the result, and it became the Vermicuiite Industry standard. In 196? rumblings were heard of a possible health hazard in the use of directly applied fireproofing materials, which contained asbestos. The percentage of asbestos in the M0N0-K0TE fireproofing formulation was low and it was not believed that its use constituted a health hazard. To confirm this belief job site air sampling was done on projects in all parts of the country. The studies showed that because M0N0-K0TE was low in asbestos content and was premixed with water and applied in a wet state the asbestos particulate matter at job sites was well below government established Threshold Limi-t Values. The consistent clamor of the Environmentalists continued and it was decided that an asbestos free product was advisable. MONO-KOTE Type IV Asbestos Free Fireproofing was fire tested in 1971 and is now available for use when required. While the asbestos controversy was raging a more subdued 1 change but one with far greater effects on the industry was slowly working its way through the E5 Committee of the American Society for Testing Materials. This Committee is responsible for writing the test procedure to determine the Fire Resistance provided by building materials and construction assemblies. The test procedure in use until January 1, 1972, had been adopted originally in 190S. It is designated as ASTM Test Method E-119. v Assemblies were not performing in Fire Tests in the manner indicated by the known performance characteristics of the materials. it Is known that the tensile strength of steel falls off sharply oo at temperatures between 1000 F. and 1200 F. Contrary to this, steel beams were passing the fire tests with temperatures which sometimes reached 1800 F. to 2000 F. Fire tests are conducted in a massive reinforced concrete cell which res ists.the?expans Ton \ - / - of the specimen as the temperatures rise.' The forcesT developed-; -- . Mr puts the assembly in compression with a resultant Increase in at*'*" * load carrying capacity. Failure only occurs then at temperatures exceeding those which would cause failure in an actuate butTding^. !>- fire where the regaining forces are not present.- r\ -: - Several years ago San Francisco, Los Angeles and Uniform- Building Code officials recognized this deficiency in the fire test procedure and had established their own criteria for acceptance l based solely on temperature. Failure point was established at i 1000O F. average at any * quarter section or 1200O F. at any single point. " i. ii The ASTM E-5 Committee worked for 10 years trying to develop a new test but it wasn't until 1970 that a compromise solution was finally reached. The revisions are complicated and confusing and there are those who believe that the problem has been compounded rather than solved. 20185568 ratings RESTRAINED and UNRESTRAINED. Under its provisions portions of a building can be consfdered restrained while other portions of the same building could be unrestrained. Temperature limitations have been established for all beams and floor assemblies but a time factor has been introduced which provides that in the testing of beams in the restrained condition the temperature of the steel shall not exceed UOO_F. average or 1300 F. maximum at any point for at least on^ hour or for -...... one half of the classification period. A Restrained"beam the could be rated at A hours if it sustained its design load for j,- - --"I. k hours and the limiting temperatures were not exceeded for Z hours. In the case of Unrestrained beams the temperature.' 1 Imi tat ions cannot be exceeded during the entire classification period. A A hour Unrestrained beam then would have to be protected with suf ficient material to prevent a temperature rise exceeding the 1100 F. average or 1300 F. maximum at any point for the full k hours. Obviously the Unrestrained beam-requirements are much more i_ severe, and except for a 100 difference in temperature are similar to the present San Francisco, Los Angeles and the Uniform Building Code requirements. Floor and Roof Assembly Tests have also been revised. They must be fully loaded and carry the load for the full time period. Temperature transmission through the floor or roof cannot exceed _o o 250 F. average or more than 325 F. at any point. Cotton waste 20185569 h 7194692 _____ cannot flame. TfmEportion of the test procedure change but a new element has been added. The beam supporting the floor or roof assembly is now considered an integral part of the assembly. The requirements for the beams in restrained or unrestrained floors or roofs is identical to those outlined previously for beams only. In unrestrained floors or roofs one other provision has been ; added. The temperature of the steel from which the deck ls> fabricated cannot exceed 1100 F. during the entire class iff cat lon**per io " V - ^ 36- Column tests have not been changed. Failure la based 01 Of* " ^ temperature and occurs when temperatures exceed 100(V F at a quarter section of the member or 1200 F. at any^srn^e^o same, test procedure and temperature limitations are appllcab both steel and concrete construction.. ?. , ' *r' $&' The whole test procedure has been further complicatedby i . of the E-5 Committee to define RESTRAINT in realistic terms.. It reads as follows "Floor and Roof Assemblies arid individual beams in buildings shall be considered restrained when the surrounding ! or supporting structure is capable of resisting substantial thermal expansion throughout the range of anticipated elevated temperatures. Constructions not complying with this definition are assumed to be free to rotate and expand and shall, therefore, be considered as unrestrained." 2O10'*70 ThFM&^Rquagc is sc* broadrarwt so vaguo^that many feeK that only the structural engineer who designed the building can i determine what is restrained or unrestrained. There are even those who insist that such a determination cannot be made realistically^ that fire loading changes in structures and who can say what is "substantial thermal expansion" or "anticipated elevated temperatures". It is this group who have for practical purposes rejected the "RESTRAINED" criteria and wilt use the more practical "UNRESTRAINED" condition.;, ' ;'V Jri' Vr The next few years will be difficult and risky for.everyoi , - A_ _,s. concerned but it will be; particularly so for those who are biMfng^^ and are doing the field application. . There is reason to believe that there wOT notr oe agreement among Code Authorities on the subjectT* Some wlli" adopt the new criteria others will reject it. There will be varying time schedules for adoption or rejection even by communities operating under the same basic code. Extreme caution plus reliance on qualified material manufacturers representatives will be necessary until some of the unresolved issues are settled. I 20l'571 All Sates Personnel From:. C. H. Wendel cc: R. M. Vintng H-A-erow" subject: Vermlcullte Ft reproof iny- WRG 000814 Watt Ptckthall was asked to prepare an article on Vermicut!te Fireproofing for the Western Plasterer magazine. Attached is a copy of his article which should prove educational for alt of us. Walt Pickthall's new title Is "Doctor Of History** akd he is now the official historian for the Pacific Region. i. CHW:me PACIFIC REGION GRACE 20185561 VERM ICULITE F IREPROOFI Past and Present ' 3.' 7194684 The old prospector poked sleepily at the remains of the previous evening's fire. He had banked it carefully and here and there tongues of flame flickered in the hot bed of coals. As the first rays of sunlight shot down from the ridge to the east his eye caught the glint of gold in the bankings he had used. His disappointment was considerable when he discovered that what at first appeared to be pea sized nuggets of the precious metal were only granules of an almost weightless\ laminated golden mineral. ~ ... Whether this or other equally plausible stories of the discovery are the real truth is relatively unimportant blit thts^' * one serves well to point up the principal physical"properties of the mineral vermiculite and the industry which developed fronr its discovery. The time would have been shortly after the end of World War I. The place, the Rocky Mountain area in Montana near the Canadian border. Present day maps show the site as Libby, Montana, where the townspeople will tell you with unabashed pride that they have the largest vermiculite deposit and mining operation in. the world and that the nearly seven million dollars Zonolite is presently spending on new facilities will triple the capacity of the operation by 1974. ' 20185562 some fift'gjPrid^years ago- the presence of the small' brown mica* like flakes in the earth he used probably went unnoticed. Certainly he would have had no way of knowing that these flakes were composed of microscopically thin laminates, between which were entrapped water cells. As the flakes grew hot frpm contact with the coals the water cells turned to steam forcing the laminates to separate. At the same time oxidization was. occurring an<i the color changed from dark brown to a highly reflective gold! The result was a granular material roughly ten times the. original size, impervious to firej, and an excellent insu?ato**t,.._ 53 Early marketing of the new discovery conceatrated'bifcthaejRime^ I * .. * *. insulation field. High resistance to fire, permanence.,?lightweight and ease of installation found ready acceptance in the marketplace. The remarkable ability to ship ore in concentrated form and expand i it at strategically located plants made the new product an economic success from the start. It was World War I lj however, that gave the fledgling business entree to the Construction Industry and the uses which are so common today. The first major job was the Mercantile National Bank Building in Dallas, Texas. As was common practice the steel was to have been encased in Concrete for fire protection. At the last minute however the government cut the steel tonnage allocation and it was 20185563 7194686 mandatory^Jl^t another fire protect lorr method be devised1 tar eliminate the dead load factor of the concrete. A fire test of vermiculite-portland cement was run at the National Bureau of Standards and passed. The steel was redesigned and the project was built with the same usable space, but with only 2/3 of the steel required in the original design. The high fire resistance of the vermicul!te-portland cement combination came to the attention of the military and with the . . -V ^ impending threat of bombing attacks on our*military' Installations thousands of cubic yards were poured on'roofs of defense fact ,v.-. vi. *- The Pentagon Building alone required 27& carToadst of; expande vermicul ite to complete jthe installations ~- The use of vermicul!te concrete has continued-to*grow and i- - - t v.-;-. . today a national group of over 100 Certified Roof Deck Applicators pour an estimated million square feet of insulating concrete dhnually. A wide range of systems is available for I installation over structural concrete or steel decks providing j high insulation values, permanence, proper drainage and maximum fire resistance. ^ i The end of World War II was marked by an immediate revival of the private sector of the Construction Industry. All materials were in short supply and steel was one of the most critical. If the needs of the country were to be met Arch i tects* and Engineers- * were going to have to utilize every tori to the ipaximum. Again 20185564 vermicul itlTplayed a major role. Research and testing had continued and a number of assemblies had successfully passed Fire Tests at Underwriters' Laboratories. Gypsum had replaced portland cement as the binder with resulting reduction in thickness requirements and application time. The West Coast led the way in acceptance of the new concept. Two major projects in Los Angeles, the Richfield Oil Building and the Prudential Insurance Building amazed old timers in the construction field with major reductions in stee\ tonnage and completion schedule. Metal lath and vermiculite gypsum plaster for columns an r vermiculite plaster suspended ceilings had permanently replaced the old slow cumbersome and expensive procedure of erecting wood forms around every member of the steel frame and then tedlousTy filling each form with concrete. Metal lath and piaster fire protection continued as the standard iI through the rest of the kO's and into the mid fifties. Other forces were at work however which were destined to replace the new concept by the end of that decade. In England laboratory work was being done with directly applied asbestos fiber encasement of structural steel. Reports reaching the United States indicated that the method had considerable promise. Not to be outdone by their European counterparts work was started on direct application of vermiculite. 20185565 Introduction and widespread use of the plaster punp accelerated : interest in the idea and in 1958 the first formulations were ready for testing. Old timers in the plastering business will recall that one of the major breakthroughs in membrane fireproofing was a vermiculite acoustical plaster ceiling. The system had passed the fire test with a 4 hour rating and gave the plastering industry its first fire rated acoustical ceiling. The basic formula for that acoustical plaster was modified and became the first vermiculite based material to pass the fife .. test for direct application on steel. ? The new system was readily accepted by the desTgn profess . /* Heating, air conditioning and lighting of major structures had become exceedingly complex and the necessity to maintain the integrity of membrane fire resistant ceilings made proper design even more difficult. The new fireproofing system,because it was directly on the steel and out of the way, provided complete flexibility and a much wider choice in finished ceilings. i It was obvious too,, that the new approach was faster and more economical than metal lath and plaster. Elimination of the time and expense of lathing accounted for most of the savings. A number of West Coast buildings were fire protected with the new system during the next few years. Among the first were the Zellerbach Building in San Francisco, a California State Office Building in Oakland and ano-ther in Los Angeles. 20185566 Th* njp*material was difficult to handle in the field. Improvement in application and reduction in thickness was needed. fireproofing was the result, and it became the Vermiculite Industry standard. In 196? rumblings were heard of a possible health hazard in the use of directly applied fireproofing materials, which contained asbestos. The percentage of asbestos in the MONO-KOTE fireproofing formulation was low and it was not believed that its use constituted a health hazard. To confirm this belief job site air sampling was done on projects in all parts of the country. The studies showed that because M0N0-K0TE was low in asbestos I content and was premixed with water and applied in a wet stated the asbestos particulate matter at job sites was well below government establ ished Threshold Limi.t Values. The consistent clamor of the Environmentalists continued and* it was decided that an asbestos free product was advisable. * < M0N0-K0TE Type IV Asbestos Free Fireproofirig was firetested . in 1971 and is now available for use when required. - While the asbestos controversy was raging a more subdued 1 change but one with far greater effects on the industry was slowly working its way through the E5 Committee of the American Society for Testing Materials. This Committee is responsible for writing the test procedure to determine the Fire Resistance provided by building materials and construction assemblies. The tesf procedure in use until January 1, 1972, had been adopted originally in 1908. It is designated as ASTM Test Method E-119. 2018556? Assemblies were not performing in Fire Tests in the manner indicated by the known performance characteristics of the materials. It is known that the tensile strength of steel falls off sharply oo at temperatures between 1000 F. and 1200 F. Contrary to this, steel beams were passing the fire tests with temperatures which sometimes reached 1800 F. to 2000 F. Fire tests are conducted in a massive reinforced concrete celt which resists fhe?axpansTonV ' -r' of the specimen as the temperatures rise. ' The forces^ deveioped: puts the assembly in compress ion with a resultant increase in , load carrying capacity. Failure only occurs then atteraperatures exceeding those which would cause failure in an actuet- bulTdingL fire where the regaining forces are not present.- ,, r~' * Several years ago San Francisco, Los Angeles ancfcUniforms Building Code officials recognized this deficiency in the fire test procedure and had established their own criteria for acceptance j based solely on temperature. Failure point was established at I O' o 1000 F. average at any quarter section or 1200 F. at any single point. i. i | The ASTM E-5 Committee worked for 10 years trying to develop a new test but it wasn't until 1970 that a compromise solution was finally reached. The revisions are complicated and confusing and there are those who believe that the problem has been compounded rather than solved. 20185568 In fta^simpfest form the new fire, test provides for two ratings RESTRAINED and UNRESTRAINED* Under its provisions portions of a building can be considered restrained while other portions of the same building could be unrestrained. Temperature limitations have been established for all beams and floor assemblies but a time factor has been introduced which provides that in the testing of beams in the restrained condition the temperature of the steel shall not exceed 1100_F. average * * ;*** or 1300 F. maximum at any point for at least oni> hour or for one half of the classification period* A Restraine could be rated at 4 hours if it sustained Itsdesig 4 hours and the limiting temperatures were not exce In the case of Unrestrained beams the temperature; 1 imitations cannot be exceeded during the entire classification period. A4 hour Unrestrained beam then would have to be protected with suf- i ficient material to prevent a temperature rise exceeding the 1100 F. average or 1300 F. maximum at any point for the full 4 hours. Obviously the Unrestrained beam requirements are much more severe, and except for a 100 difference in temperature are similar to the present San Francisco, Los Angeles and the Uniform Building Code requirements. Floor and Roof Assembly Tests have also been revised. They must be fully loaded and carry the load for the full time period. Temperature transmission through the floor or roof cannot exceed oo 250 F. average or more than 325 F. at any point. Cotton waste 20185569 but a new element has been added. The beam supporting the floor or roof assembly Is now considered an integral part of the assembly. The requirements for the beams In restrained or unrestrained floors or roofs is identical to those outlined previously for beams only.. In unrestrained floors or roofs one other provision has been added. The temperature of the steel from which the deck- Is- fabricated ~ .-*>V -+ vcannot exceed 1100 F. during the entire classIf|feat Ion Column tests have not been changed. Failure labased :*? * temperature and occurs when temperatures exceed 100QT '-i quarter section of the member or 1200 F. at any^sfn^ same, test procedure and temperature 1 imitations are app.lica61 both steel and concrete construction.. ' ! - ' ' The whole test procedure has been further complicatedfcby of the E*5 Committee to define RESTRAINT in realistic terms., ir reads as follows "Floor and Roof Assemblies arid individual beams in buildings shall be considered restrained when the surrounding ! or supporting structure is capable of resisting substantial thermal expansion throughout the range of anticipated elevated temperatures. Constructions not complying with this definition are assumed to be free to rotate and expand and shall, therefore, be considered as unrestrained." 20185*70 v je Is so broadband so vague* thar many fee only the structural engineer who designed the building can 1 determine what is restrained or unrestrained. There are even those who insist that such a determination cannot be made rea1is tica11 y; that fire loading changes in structures and who can say what is "substantial thermal expansion" or "anticipated elevated temperatures". It is this group who have for practical purposes rejected the "RESTRAINED" criteria and wilt use the more . Tvy. - ' ? practical "UNRESTRAINED" condition, . v ,^ I ^ r"'^ -V The next few years will be difficult and risky foreveryojMp^*' concerned but it will be particularly so far those who are blqflim and are doing the field application. . There is reason to believe that there wff^no^lie agreement I , ." -r* - X r" among Code Authorities on the subject,* Some wilt adopt the new criteria others will reject it. There will be varying time schedules for adoption or rejection even by communities operating under the same basic code. Extreme caution plus reliance on qualified material manufacturers representatives will be necessary until some of the unresolved issues are settled. I i 20185*71 |w\ 'Tv , * ** :`>iy - 'T--- ** _-'. ' yy. &:**: --- "^^i^'-v.:^-- --.W.. * ^ &* INTEROFFICE CORRESPONDENCE ;?/- ' TOr Managers* PlantFHsnagers All Sales Personnel datei March 28, 1973 subject: Vermicullte Fireproofing From:. C. H. Wendel cc: R. M. Vining H. A. Brown WRG 0009' 1 Walt PIckthall was asked to prepare an article on Vermicullte Fireproofing for the Western Plasterer magazine. Attached Is a copy of his article which should prove educational for alt of us. Walt PIckthall1s new title is "Doctor Of History** and he Is now the official historian for the Pacific Region. CHW:me ./ *C ,,:? *v. -***... " PACIFIC REGION 201855b! 4 "V* '** >--*<t*3* VERMICULITE Ft REPROOF IHp^^ 'IJjBv Past and Present The old prospector poked sleepily at the remains of the previous evening's fire. He had banked it carefully and here and there tongues of flame flickered in the hot bed of coals. As the first rays of sunlight shot down from the ridge to the east his eye caught the glint of gold in the bankings he had used. His disappointment was considerable when he discovered that what at first appeared to be pea sized nuggets of the precious metal were only granules of an almost weightTess\laminated golden mineral. Whether this or other equally plausible stories of the discovery are the real truth is relatively unimportant but this- ` one serves well to point up the principal physFeat properties of the mineral vermiculite and the industry which developed from j_' its discovery. The time would have been shortly after the end of World War i. The place, the Rocky Mountain area in Montana near the Canadian border. Present day maps show the site as Libby, Montana, where the townspeople will tell you with unabashed pride that they have the largest vermiculite deposit and mining operation in- the world and that the nearly seven million dollars Zonolite is presently spending on new facilities will triple the capacity of the operation by 1?74. '# 20185562 "prospectembanked hfsr lonely fl re^.thet some fircf^ptfdu.years ago= the presence of the small brown mica* like flakes in the earth he used probably went unnoticed. Certainly he would have had no way of knowing that these flakes were composed of microscopically thin laminates, between which were entrapped water cells. As the flakes grew hot frpm contact with the coals the water cells turned to steam forcing the laminates to separate. At the same time oxidization was occurring t?, -. * *- and the color changed from dark brown to a highly reflective gold^ The result was a granular material roughly ten times the. original size, impervious to firet, and an excel lent insulatoi*^.! basHEI*: Early marketing of the new discovery concent rated'on^thaiiome^ ,| *' ... -r. insulation field. High iresistance to fire, permanence ^lightweight : '' - - *'$* and ease of installation found ready acceptance in the market place. s The remarkable ability to ship ore in concentrated form and expand i it at strategically locaited plants made the new product an economic success from the start. It was World War I Ij however, that gave the fledgling business entree to the Construction industry and the uses which are so common today. The first major job was the Mercantile National Bank Building in Dallas, Texas. As was common practice the steel was to have been encased in Concrete for fire protection. At the last minute however the government cut the steel tonnage allocation and it was 20185563 v 7194686 -; mandatorytfiat another fire protection method be devised ta eliminate the dead load factor of the concrete. A fire test of v vermicul1te-portland cement was run at the National Bureau of Standards and passed. The steel was redesigned and the project was built with the same usable space, but with only 2/3 of the steel required in the original design. The high fire resistance of the vermIcuIIte-portland. cement combination came to the attention of the mil Itary and with the .. j V-'* *->> ** ` '1 Impending threat of bombing attacks on oup.flrfTttanr Installations i .-r thousands of cubic yards were poured orv roofs of defense facilmties^s- The Pentagon Building alone required 275 carloads of expandedP;^-.:' vermicul ite to complete the installation. -' The use of vermicul ite concrete has continue-d'to g` row and rv*- r~3n. today a national group of over 100 Certified Roof Deck Applicators I pour an estimated ___________ million square feet of insulating i concrete dhnuaily. A wide range of systems is available for I installation over structural concrete or steel decks providing high insulation values, permanence, proper drainage and maximum fire resistance. i p The end of World War II was marked by an immediate revival I of the private sector of the Construction Industry. All materials were in short supply and steel was one of the most critical. If the needs of the country were to be met Archi tects* and Engineers- were going to have to utilize every tori to the iTiaximum. Again 2018556* 7194687 vermiculite played a major role. Research and testing had continued! and a number of assemblies had successfully passed Fire Tests at Underwriters' Laboratories. Gypsum had replaced port land cement as the binder with resulting reduction in thickness requirements and application time. The West Coast led the way in acceptance of the new concept. Two major projects in Los Angeles* the Richfield Oil Building and the Prudential Insurance Building amazed old timers in the construction field with major reductions in stee\ tonnage and completion schedule. Metal lath and vermiculite gypsun plaster for columns an vermiculite plaster suspended ceilings had permanently replaced the old slow cumbersome and expensive procedure of erecting wood forms around every member of the steel frame and then tediously filling each form with concrete. Metal lath and piaster fire protection continued as the standard through the rest of the 40's and into the mid fifties. Other forces were at work however which were destined to replace the new concept by the end of that decade. In England laboratory work was being done with directly applied asbestos fiber encasement of structural steel. Reports reaching the United States indicated that the method had considerable promise. Not to be outdone by their European counterparts work was started on direct application of vermiculite. 2018556*5 Introraction and widespread use of the plaster pump accelerated interest in the idea and in 1958 the first formulations were ready for testing. Old timers in the plastering business will recall that one of the major breakthroughs in membrane fireproofing was a vermiculite acoustical plaster ceiling. The system had passed the fire test with a 4 hour rating and gave the plastering industry its first fire rated acoustical ceiling. ,The basic formula for that acoustical plaster was modified \ and became the first vermiculite based material to pass the fl{e test for direct application on steel. I The new system was readily accepted by the desfgn profession. Heating, air conditioning and lighting of major structures had become exceedingly complex and the necessity to maintain the integrity of membrane fire resistant ceilings made proper design even more difficult. The new fireproofing system,because it was directly on the steel and out of the way, provided complete flexibility and a much wider choice in finished ceilings. i It was obvious too,! that the new approach was faster and more economical than metal lath and plaster. Elimination of the time and expense of lathing accounted for most of the savings. A number of West Coast buildings were fire protected with the new system during the next few years. Among the first were the Zellerbach Building in San Francisco, a California State Office Building in Oakland and ano-ther in Los Angeles. 20185566 v V r* ,719468 *1* The rnWr'material was difficult to handle in the field. improvement in application and reduction in thickness was needed. M0N0-K0TE fireproofing was the result, and it became the Vermiculite industry standard. in 196? rumblings were heard of a possible health hazard in the use of directly applied fireproofing materials, which contained asbestos. The percentage of asbestos in the M0N0-K0TE fireproofing formulation was low and it was not believed that its use constituted a health hazard. To confirm this belief job site air sampling was done on projects in all parts of the country. The studies showed that because M0N0-K0TE was low in asbestos content and was premixed with water and applied in a wet state the asbestos particulate matter at job sites was well below government established Threshold Limi-t Values. The consistent clamor of the Environmentalists continued and it was decided that an asbestos free product was advisable. < MONO-KOTE Type IV Asbestos Free Fireproofing was fire-tested in 1971 and is now available for use when required. While the asbestos controversy was raging a more subdued 1 change but one with far greater effects on the industry was slowly working its way through the E5 Committee of the American Society for Testing Materials. This Committee is responsible for writing the test procedure to determine the Fire Resistance provided by building materials and construction assemblies. The tesf procedure in use until January 1, 1972, had been adopted originally in 1908. It is designated as ASTM Test Method E-119. 201855&7 Assemblies were not performing in Fire Tests in the manner indicated by the known performance characteristics of the materials. It is known that the tensile strength of steel falls off sharply oo at temperatures between 1000 F, and 1200 F. Contrary to th!s steel beams were passing the fire tests with temperatures which sometimes reached 1800 F. to 2000 F. Fire tests are conducted in a massive reinforced concrete cel) which res is\\ts .-"thV-e'-*?**.--e7 xpans ion. of the specimen as the temperatures rise.' The forcer"developed^ V~ X-'" puts the assembly in compression with a resultant increase inTtr^ load carrying capacity. Failure only occurs then at temperatures exceeding those which would cause failure in- an actuej^butTding^^ i- . fire where the regaining forces are not present.- '.-Or'. ,, rv;' Several years ago San Francisco, Los Angeles and Uniform* Building Code officials recognized this deficiency In the fire test procedure and had established their own criteria for acceptance based solely on temperature. Failure point was established at i 1000O F. average at any *quarter section or 1200O F. at any single point. ii ' The ASTM E-5 Committee worked for 10 years trying to develop a new test but it wasn't until 1970 that a compromise solution was finally reached. The revisions are complicated and confusing and there are those who believe that the problem has been compounded rather than solved. 20185568 ratings RESTRAINED and UNRESTRAINED* Under Its provisions portions of a building can be consTdered restrained while other portions of the same building could be unrestrained. Temperature limitations have been established for all beams and floor assemblies but a time factor has been introduced which provides that in the testing of beams in the restrained condition the temperature of the steel shall not exceed lT00a_F. average * *** or 1300 F. maximum at any point for at least onfe hour or for * ' '-* ^. one half of the classification period. A Restrained beam then# could be rated at 4 hours if it sustained its design load for'jp;". 4 hours and the limiting temperatures were not exceeded for 2 hours, in the case of Unrestrained beams the temperature. 1imI tat ions j, *- cannot be exceeded during the entire classification period. A- 4 hour Unrestrained beam then would have to be protected with suf ficient material to prevent a temperature rise exceeding the 1100 F. average or 1300 F. maximum at any point for the full 4 hours. Obviously the Unrestrained beam'requirements are much more iQ severe, and except for a 100 difference in temperature are similar to the present San Francisco, Los Angeles and the Uniform Building Code requirements. Floor and Roof Assembly Tests have also been revised. They must be fully loaded and carry the load for the full time period. Temperature transmission through the floor or roof cannot exceed oo 250 F. average or more than 325 F. at any point. Cotton waste 20105569 * cannot, Fgrilta from passage flame.' TffflE port l on of the test procedure has no A! but a new element has been added. The beam supporting the floor or roof assembly Is now considered an integral part of the assembly. The requirements for the beams in restrained or unrestrained floors or roofs is identical to those out 1ined previously for beams only. In unrestrained floors or roofs one other provision has been ; added. The temperature of the steel from which the deck Is> fabricated cannot exceed 1100o F. during the entire class ifica-t longer I `V & Column tests have not been changed. Failure; la based ..Ti. .* temperature and occurs when temperatures exceed lOOO^Fw at '-r . quarter section of the member or 1200 F. at eny^slh^e^jo same, test procedure and temperature limitations ana appLicab both steel and concrete construction.. The whole test procedure has been further complicated-by i . of the E-5 Committee to define RESTRAINT in realistic terms.. It reads as fol lows "Floor and Roof Assemblies arid individual beams in buildings shall be considered restrained when the surrounding ! or supporting structure is capable of resisting substantial thermal expansion throughout the range of anticipated elevated temperatures. Constructions not complying with this definition are assumed to be free to rotate and expand and shall, therefore, be considered as unrestrained." 20ie5*70 * only the structural engineer who designed the building can i determine what is restrained or unrestrained. There are even those who insist that such a determination cannot be made realistical1 y; that fire loading changes in structures and who can say what is "substantial thermal expansion" or "anticipated elevated temperatures", it is this group who have for practical purposes rejected the "RESTRAINED" criteria and wilt, use the more practical "UNRESTRAINED" condition. S'-h 'T The next few years will be difficult and risky for,everyone -m.- concerned but it will be particularly so for those who are bidofnc Sii. and are doing the field application. . *' -- - -- k /&**!** ' r.` There is reason to believe that there wFli noirfce agreement i, .' . among Code Authorities on the subject.* Some wilt adopt the new j" criteria others will reject it. There will be varying time schedules for adoption or rejection even by communities operating under the same basic code. Extreme caution plus reliance on qualified material manufacturers representatives will be necessary until some of the unresolved issues are settled. I i * zo