The structural collapse of the Twin Towers of the World Trade Center occurred in a time period far shorter than its statutory Fire Code rating. Speculation gave rise to theories that the steel had buckled because of the substitution of the original asbestos-containing fireproofing with a non-asbestos-containing vitreous fibre formulation. The substitution was thought to have come about due to New York City’s 1972 ban of such materials in construction. The use of substitute material in the Towers actually pre-dated the New York City ban by almost 2 years. Although, the substitute material may have had the same thermal rating for fire, its characteristics concerning durability during service are now known to have been inferior. At the time of application and construction, no performance criteria were available concerning application thickness, adherence character, compressive strength, or density. These factors are now thought to have played a major role in the heating of the structural steel and its subsequent failure. The ban of asbestos-containing spray fireproofing was probably a reasonable conclusion for the time, only if the substitute material performed as well as the material which it replaced. However it did not. The issues today focus on the necessity to re-inspect buildings sprayed with asbestos substitutes during the time period 1972–1977, especially those structures that employed the same light-weight floor truss design, and measure their serviceability according to now established standards.

Copyright / Drug Dosage / Disclaimer
Copyright: All rights reserved. No part of this publication may be translated into other languages, reproduced or utilized in any form or by any means, electronic or mechanical, including photocopying, recording, microcopying, or by any information storage and retrieval system, without permission in writing from the publisher.
Drug Dosage: The authors and the publisher have exerted every effort to ensure that drug selection and dosage set forth in this text are in accord with current recommendations and practice at the time of publication. However, in view of ongoing research, changes in government regulations, and the constant flow of information relating to drug therapy and drug reactions, the reader is urged to check the package insert for each drug for any changes in indications and dosage and for added warnings and precautions. This is particularly important when the recommended agent is a new and/or infrequently employed drug.
Disclaimer: The statements, opinions and data contained in this publication are solely those of the individual authors and contributors and not of the publishers and the editor(s). The appearance of advertisements or/and product references in the publication is not a warranty, endorsement, or approval of the products or services advertised or of their effectiveness, quality or safety. The publisher and the editor(s) disclaim responsibility for any injury to persons or property resulting from any ideas, methods, instructions or products referred to in the content or advertisements.
You do not currently have access to this content.