A NATIONAL PLAN FOR AMERICAN FORESTRY 1369 



FIRE RETARDANTS 



The development of a complete, inexpensive fire-resistant treat- 

 ment would do much to regain immense markets for wood that are 

 now closed. Building code and underwriters' requirements limit the 

 use of wood for exterior walls in residential, industrial, and com- 

 mercial buildings in urban areas. To a less extent wood framing 

 is handicapped in competition with less combustible materials. 

 Fire-resistant treatments are now available but too expensive for 

 general use. Recent studies encourage hope for marked improve- 

 ment. Several highly effective chemicals are known, and combina- 

 tions of certain chemicals give promise of even better results in 

 respect to economy, noncorrosive effect, permanance, and other 

 advantages. A combined treatment ^ embodying fire resistance, 

 decay and insect resistance, and reduction of shrinking and swelling 

 properties is a major objective that may ultimately be attained. 



PREVENTION OF SHRINKAGE 



A successful treatment to prevent shrinking and swelling would 

 do more than any other single accomplishment to simplify and 

 cheapen the use of wood in doors, sash, trim, furniture, floors, and a 

 host of other wood products. It would also result in so much better 

 service and satisfaction that the popularity of wood for these pur- 

 poses would increase, and expanding markets would inevitably 

 result. Chemicals have already been found that reduce the shring- 

 age as much as 90 percent, but the wood so treated shows a decided 

 tendency to become wet and drip in a very damp atmosphere. The 

 problem is to find new chemicals of high effectiveness that are free 

 from this and other disqualifying objections or to find ways to change 

 the injected material to nonhygroscopic forms. Increasing knowl- 

 edge promises that the desired result is by no means impossible. 



PREVENTION OF DECAY 



Decay is a major menace to the permanence of wooden structures. 

 Unprotected wood in service is being lost through premature decay 

 at a rate comparable hi magnitude only % with the destruction caused 

 by forest fires. Research and experience have shown that decay 

 prevention is possible by the proper use of preservatives and often 

 by improvements in design and construction to avoid the conditions 

 that favor decay. Railroads and other public utilities annually treat 

 millions of cubic feet of ties, poles, piling, construction timber and 

 miscellaneous lumber with creosote, zinc chloride, and other preserva- 

 tives. The serviceable life of the wood is increased two to ten times, 

 and enormous financial savings result. Wood is thus enabled to re- 

 tain large markets which would be closed to it if only the relatively 

 short life of untreated wood under decay-producing conditions were 

 attainable. The sphere of research in the continued development of 

 wood preservatives and treating processes is very large, necessitating 

 the collaboration of the engineer, the physicist, the chemist, the en- 

 tomologist, the plant pathologist, and the toxicologist. 



The desirability of lower treating costs is obvious. The danger of 

 reducing the strength or causing unsightly defects during treatment is 

 very real. The total recognized loss in value from this source amounts 



