Free Encyclopedia of Building & Environmental Inspection, Testing, Diagnosis, Repair

Ask a Question or Search InspectAPedia

• HOME
• AIR CONDITIONING
• ELECTRICAL
• EXTERIORS
• HEATING
• HOME INSPECTION
• INTERIORS
• PLUMBING
• ROOFING
• SEPTIC SYSTEMS
• STRUCTURE
• WATER SUPPLY

• ENERGY SAVINGS
• ENVIRONMENT
• INDOOR AIR IAQ
• INSULATION
• MOLD INSPECT TEST REMOVE
• NOISE
• ODORS
• SOLAR ENERGY
• VENTILATION
• EXPERTS DIRECTORY
• CONTACT US

This article assists in the recognition of transite pipe used for chimneys or heating flues and discusses potential hazards of this material when it is found in buildings. Transite pipe is an asbestos-cement product which was used for both HVAC ducts and for chimney or flue material to vent gas-fired appliances. This document assists building buyers, owners or inspectors who need to identify asbestos materials (or probable-asbestos) in buildings by simple visual inspection. We provide photographs and descriptive text of asbestos insulation and other asbestos-containing products to permit identification of definite, probable, or possible asbestos materials in buildings.

Cement-asbestos transite pipe was also used for water piping in some communities, as we discuss at Transite Pipe Water Supply Piping.

Because asbestos cement transite pipe chimneys may have operating and safety problems, concerns completely separate from asbestos handling questions, readers should see our chimney inspection suggestions at CHIMNEY INSPECTION DIAGNOSIS REPAIR.

While an expert lab test using polarized light microscopy may be needed to identify the specific type of asbestos fiber, or to identify the presence of asbestos in air, dust or drinking water samples, many asbestos-containing building products not only are obvious and easy to recognize, but since there were not other look-alike products that were not asbestos, a visual identification of this material can be virtually a certainty in many cases.

Contact us to suggest text changes and additions and, if you wish, to receive online listing and credit for that contribution.

© Copyright 2012 InspectAPedia.com, All Rights Reserved. Information Accuracy & Bias Pledge is at below-left. Use page top links to major topics or use links at the left of each page to navigate within topics and documents at this website. Green links show where you are in a document series or at this website.

TRANSITE PIPES OR DUCTS - Transite Chimney and Duct Material Warnings

Unsafe transite pipe heating flue vents may only be noticed by a careful building inspection such as shown in these rooftop photographs of a transite flue vent pipe which deteriorated, became swollen, and risk becoming blocked. In cold climates with these vents from the 1950's era, the real hazard is not so much asbestos fibers as the dangerous obstruction of the vent/flue by the deterioration of the interior of the pipe. [Photographs above and text just above on transite flue deterioration were provided courtesy of Roger Hankey].

In the transite chimney vent photo at above right we note that the exterior has been painted black. We don't know why, possibly the naturally gray-white transite flue was painted black for cosmetic reasons, or perhaps in an effort to slow down its surface deterioration.

Fire Clearance Requirements for & Label Descriptions of Asbestos Cement or Transite Heating Flues & Chimneys

In use as a gas-fired appliance chimney/vent transite pipe may have been classed as a type "B" flue vent which required 1" clearance from combustibles in some jurisdictions. But as we indicate below, the fire clearance required for transite pipe or cement-asbestos pipe flues and chimneys varied from 1" to 3" and limited temperatures to 330 to 550 F depending on the clearance.

Ervin McKinney kindly provided a copy of a November 1948/1949 Underwriters Laboratories UL List of Inspected Gas, Oil, and Miscellaneous Appliances that includes specifications for Outlet and Vent Piping (540 116). That document indicates that

Vent piping of noncombustible, corrosion resistant material of adequate strength and heat-insulating value is acceptable according to Section 1006 of the Building Code Recommended by the National Board of Fire Underwriters (1949 Edition.) This piping is intended for use only with gas-burning appliances which produce flue gas temperatures not in excess of 550 F.

Unless otherwise indicated in specific listings, spacing to combustible material shall be not less than 1 in. provided that for vents of floor furnaces spacing shall be not less than 3 in. for a distance of not less than 3 ft. from the outlet of the draft hood.

Asbestos Cement Chimney & Flue Venting Products described in this 1948-1949 document include

Enderle, Inc., Ltd., Frank X., Los Angeles Calif.

Cylindrical outlet and vent piping of asbestos, sand, and cement, bell and spigot type.

Markings: "Enderle Vent" stenciled on each length of pipe and fitting.

Cylindrical outlet and vent piping of cement and asbestos having a galvanized iron outer jacket.

Markings: "Enderle Cased Vent" stenciled on each length of pipe and fitting.

Johns-Manville Corp. New York, NY., [Transite or cement asbestos flue vent and chimney piping description]

Consists essentially of cement and asbestos fiber built up in cylindrical and oval form: supplied with couplings, elbows, tees, joint cement, etc.

Suitable for use with 1-in. clearance to combustibles when flue gas temperatures do not exceed 330 F, or with 1 1/2-in. ventilated clearance when flue gas temperatures do not exceed 550 F.

Authorities having jurisdiction should be consulted regarding installation.

Marking: "J-M Transite Flue Pipe for Gas Venting" on each section of piping and on each fitting.

This same document also describes several other flue gas vent piping products made of vitreous coated steel, asbestos, sand, and cement, sand and pumicite with aluminum collar joints, sheet aluminum tube and asbestos insulating or steel spring spacer with an outer shell of galvanized sheet metal, and other aluminum and galvanized sheet metal piping.

See this PDF copy of 1948/1949 Underwriters Laboratories UL List of Inspected Gas, Oil, and Miscellaneous Appliances.

Carbon monoxide hazards with transite asbestos cement chimneys

Where transite pipe (asbestos-cement pipe) has been used as a building chimney to vent combustion gases, if the chimney becomes blocked there could be a dangerous carbon monoxide hazard in the building.

The transite pipe chimney - carbon monoxide hazard occurs when the (usually above-roof outdoor portion) of a transite pipe chimney becomes soft with age and exposure to weather, leading to swollen chimney sides and even chimney internal collapse.

The swollen and collapsing transite pipe chimney blocks the venting of exhaust gases from the building heating equipment.

Blocking the venting of exhaust gases, particularly for natural gas or LP gas fired heating appliances, is very likely to interfere with proper combustion at the appliance itself. In turn, this condition results in the production of carbon monoxide at high levels.

1. Ultimately transite pipe cement asbestos chimney vent flue that becomes blocked creates a multiple safety hazard:
2. Increased production of carbon monoxide at the heating appliance
3. Failure to vent combustion gases fully outside the building
4. Leakage of carbon monoxide gases into the building

See CHIMNEY INSPECTION & REPAIR GUIDE and see CARBON MONOXIDE for more information.

Transite pipe, which contains significant percentage of asbestos fibers, was often used for heating ducts and on occasion heating and cooling ducts in older buildings.

The transite pipe was used in a buried-in-slab construction methods which placed the transite piping below or in a building floor slab, and asbestos-containing transite pipe ducts were also used in exposed areas such as shown in the crawl space photographs above. [Photo above showing transite duct material is provided courtesy of Thomas Hauswirth, a Connecticut home inspector.]

Our photo below shows a transite (asbestos cement) chimney on the exterior of an older home. This chimney may be too cold to perform safely, especially if venting a gas-fired appliance. At CHIMNEY INSPECTION DIAGNOSIS REPAIR we describe chimney inspections in detail.

A Brief Summary of Health Hazards from Handling Transite Pipe or Asbestos Cement Piping for Vents, Chimneys, or Air Ducts

Where are the chief health risks with cementious asbestos materials?

Transite pipe, whether it has been used as an air duct, flue vent, chimney, or water pipe, is still a cementious material that is unlikely to release high levels of airborne fibers when it is in good condition.

Touching transite pipe, or simply removing and disposing of an intact section of this material from a building by carrying it outside should not release a significant level of airborne asbestos fibers unless:

• The transite pipe was deteriorated, soft, friable - crumbly and easily made into powder and debris - this can happen where the material was exposed to weather such as the upper portion of a flue vent, plumbing vent, or chimney where it extends above a building roof or where transite air ducts were placed below a floor slab and exposed to water.
• The transite pipe was removed or attacked using power tools such as saws, grinders, or sanders, producing asbestos-containing dust
• The transite pipe was removed or attacked during demolition using hammers and similar implements

In summary, if it has become soft and friable, or if transite pipe is damaged or is cut mechanically (such as by using power equipment), friable, airborne asbestos fibers may be generated - a health and potentially a costly cleanup concern.

Incorrect spellings of transite piping or transite duct material that we've seen include transit pipe, transit ducts, Transide pipe, transide ducts, tranisite pipe, and transight pipe. "Transite" is the correct spelling.

Questions & Answers regarding this article

.

Recommend / Share this Article            

...

Technical Reviewers & References

• InspectAPedia.com^® - Daniel Friedman - Publisher & Editor.
• InspectAPedia Bookstore lists recommended books, organized by topic & available for purchase. Most of our articles also include a list of recommended books for the specific article topic as well as other references, and information sources.
• Critique, contributions wanted: Contact Us to suggest corrections or additions to articles at this website, and if you wish, to receive online listing and credit as a contributor. Particular thanks are due to the many experts and also consumers who read and critique technical articles at InspectAPedia.com.
• Additional technical contributors & reference sources for this article are listed below.

Use links just below or at the left of each page to navigate this document or to view other topics at this website. Green links show where you are in our document or website.

• ASBESTOS HVAC DUCTS - Guide to Identification of Asbestos Materials On or In Heating and Cooling Duct Work: carbon monoxide hazards of transite chimneys and vents
• ENVIRONMENTAL HAZARDS - INSPECT, TEST, REMEDY - Environmental Hazard Detection, Testing, Repair, Illness, Symptoms, & Prevention in buildings
• IDENTIFICATION of ASBESTOS in buildings - Asbestos Identification in buildings: How to find & identify asbestos-containing materials
• TRANSITE PIPE AIR DUCTS - Hazards of Asbestos-containing Transite Pipe HVAC Ducts: duct collapse, mold, radon, asbestos fiber release
• Transite Pipe Chimneys & Flues - Guide to Identifying Asbestos Transite Chimneys & Flues & their Hazards in buildings
• Transite Pipe Water Supply Piping - Guide to Identifying Asbestos Cement Transite Water Pipes & their Hazards in buildings

ENVIRONMENTAL HAZARDS - INSPECT, TEST, REMEDY

ASBESTOS FLOORING HAZARD REDUCTION
ASBESTOS-FREE INSULATION MATERIALS
ASBESTOS IDENTIFICATION IN buildings
  ASBESTOS AIR DUCTS
  Asbestos Air Duct Vibration Dampers
  ASBESTOS in CARPETING, PADDING
  ASBESTOS CEILING TILES, Asbestos-Containing
  ASBESTOS DUCTS, HVAC
  ASBESTOS DUCT INSULATION, Asbestos Paper
  ASBESTOS DUCTS, Transite Pipe
  ASBESTOS FIREPROOFING SPRAY-On Coatings
  ASBESTOS FLOOR TILE IDENTIFICATION
  ASBESTOS FLOOR TILE Laboratory Procedures
  ASBESTOS FLOOR TILE PHOTO ID GUIDE
  ASBESTOS FLOORING HAZARD REDUCTION
  ASBESTOS FLOORING REMOVAL GUIDE
  Asbestos Foamed-Over
  ASBESTOS INSULATION
  ASBESTOS PAPER DUCT INSULATION
  ASBESTOS PIPE INSULATION
  ASBESTOS ROOFING, CEMENT & FIBER CEMENT
  ASBESTOS ROOFING / SIDING DUST
  ASBESTOS SIDING CEMENT & FIBER CEMENT
  Asbestos in unusual places
  Asphalt-asbestos Paints & sealants
  Carbon Nanotube Materials
  TRANSITE PIPE AIR DUCTS
  Transite Pipe Chimneys & Flues
  Transite Pipe Water Supply Piping
  VERMICULITE INSULATION
ASBESTOS FLOORING HAZARD REDUCTION
ASBESTOS FLOORING REMOVAL GUIDE
ASBESTOS List of Asbestos-Containing Products
ASBESTOS MATERIAL REGULATIONS
ASBESTOS MATERIAL REGULATIONS Update
ASBESTOS MATERIAL REGULATIONS, OSHA Roofing/Siding
ASBESTOS Photo Guide to Materials / Products
ASBESTOS RISK ASSESSMENT
ASBESTOS REMOVAL, Amateur, Incomplete
Asbestos Removal, Certification
ASBESTOS REMOVAL, Wetting Guidelines
Asbestos Under the Microscope

• Roger Hankey is principal of Hankey and Brown home inspectors, Eden Prairie, MN. Mr. Hankey is a past chairman of the ASHI Technical Committee and the ASHI Standards Committee. Mr. Hankey serves as co-chairman of ASHI legislative committee, and has served in other ASHI professional and leadership roles. Contact: 952 829-0044 - hankeybrown@comcast.net
• Ervin McKinney, a gas industry expert in Lorain OH, kindly provided this PDF copy of 1948/1949 Underwriters Laboratories UL List of Inspected Gas, Oil, and Miscellaneous Appliances. October 2010

Books & Articles on Building & Environmental Inspection, Testing, Diagnosis, & Repair

• Our recommended books about building & mechanical systems design, inspection, problem diagnosis, and repair, and about indoor environment and IAQ testing, diagnosis, and cleanup are at the InspectAPedia Bookstore. Also see our Book Reviews - InspectAPedia.

Asbestos Hazard, Testing, Removal, References & Products

• Environmental Health & Investigation Bibliography - our own technical library on indoor air quality inspection, testing, laboratory procedures, forensic microscopy, etc.
• ASBESTOS IDENTIFICATION IN buildings How to find and recognize asbestos in buildings - visual inspection methods, list of common asbestos-containing materials
• Asbestos Identification and Testing References
• Asbestos Identification, Walter C.McCrone, McCrone Research Institute, Chicago, IL.1987 ISBN 0-904962-11-3. Dr. McCrone literally "wrote the book" on asbestos identification procedures which formed the basis for current work by asbestos identification laboratories.
• Stanton, .F., et al., National Bureau of Standards Special Publication 506: 143-151
• Pott, F., Staub-Reinhalf Luft 38, 486-490 (1978) cited by McCrone
• Asbestos in Good Condition
• Asbestos in Good Condition
• Asbestos in Your Home U.S. EPA, Exposure Evaluation Division, Office of Toxic Substances, Office of Pesticides and Toxic Substances, U.S. Environmental Protection Agency, Washington,D.C. 20460
• Asbestos HVAC Ducts and Flues field identification photos and guide
• Asbestos NESHAP Adequately Wet Guidance, EPA340/1-90-019, December 1990, U.S. ENVIRONMENTAL PROTECTION AGENCY, Office of Air Quality Planning and Standards, Stationary Source Compliance Division, Washington, DC 20460,original web source: http://www.epa.gov/region04/air/asbestos/awet.htm
• Asbestos paper duct wrap
• Asbestos products and their history and use in various building materials such as asphalt and vinyl flooring includes discussion which draws on Asbestos, Its Industrial Applications, D.V. Rosato, engineering consultant, Newton, MA, Reinhold Publishing, 1959 Library of Congress Catalog Card No.: 59-12535 (out of print, text and images available at InspectAPedia.com).
• Asbestos Transite Chimneys, Flues, & Pipes in buildings
• Asbestos under the microscope
• Asbestos Vibration Dampers & Asbestos in the Air Handler
• Ceiling tiles: How to recognize ceiling tiles that may contain asbestos
• Examples of unusual uses of asbestos in buildings
• Fiberglass: Indoor Air Quality Investigations: Health Concerns About Airborne Fiberglass: Fiberglass in Indoor Air from HVAC ducts, and Building Insulation
• Enviro-Scare: Electric Power Lines, Electromagnetic Fields, Cancer Risk, & "Enviro-Scare" - The Normal Curve Cycle of Public Fear of Environmental Issues
• Dust from the World Trade Center collapse following the 9/11/01 attack: the lower floors of this building contained spray-on fire-proofing asbestos materials.
• Asbestos Information Links: Asbestos Detection, Testing, Recognition, Hazards, Field Photos, and Information Sources, including health-related links such as legal services and information about mesothelioma and other cancers.
• "Handling Asbestos-Containing roofing material - an update", Carl Good, NRCA Associate Executive Director, Professional Roofing, February 1992, p. 38-43
• EPA Guidance for Controlling Asbestos-Containing Materials in buildings, NIAST, National Institute on Abatement Sciences & Technology, [republishing EPA public documents] 1985 ed., Exposure Evaluation Division, Office of Toxic Substances, Office of Pesticides and Toxic Substances, U.S. Environmental Protection Agency, Washington,D.C. 20460