University of Georgia
Extension Agronomist-Tobacco

Topics for this week include:

After the 7th meeting of the group since December 20, 1999, the Tobacco Industry Leadership Group (TILG) has agreed in concept to a proposed funding program to assist growers with the costs of purchasing and installing heat exchangers in curing barns to reduce the levels of tobacco specific nitrosamines (TSNA), and have agreed to a set of recommendations (standards) for heat exchanger construction and installation.

Included is the idea of a Certification program to start July 1, 2001 which would certify the use curing systems which do not introduce the products of combustion into the curing barn in order to receive price support. The final version of the proposal will take shape over the next few weeks and final signatures of all participating parties are yet to be obtained. While $85 million sounds like a large pot of money, in order to receive any of the money growers will have to commit to retrofitting their barns with orders for heat exchangers before equipment companies will produce them.

Heat exchangers will have to be manufactured, installed, and certified as performing according to specs by the manufacturer/installer and the grower will have to submit receipts in order for the check to be processed to reimburse him for approximately half the incurred expenses. In order to receive the $3,000 per barn amount, growers will have to act quickly to make these updates prior to August 1, 2000.

Production of heat exchangers will start slowly, with possible improvements in design and heat efficiency as later models are produced. Most equipment manufacturers agree that production of between 2,000 and 3,000 heat exchangers from each manufacturer during the first 5 to 6 months of production will be a best case scenario. Estimates are that 30,000 to 40,000 barns will need to be retrofitted or replaced.

The TILG Sub-committee has discussed the importance of not identifying tobacco cured with heat exchangers from that cured in conventional barns until a Certification Program is put into place and requires it. However, unofficial knowledge of tobacco from retrofitted barns will likely make a difference in the demand for this tobacco. Possible random sampling of tobacco offered for sale for TSNA levels has been discussed as a means to gauge the extent of the retrofitting process.

If the Certification program is to start July 1, 2001, growers will have to begin to install early production models of the heat exchangers to insure production and installation of an adequate number to cure the crop for the 2001 season.

The following was compiled by: Dr. Michael D. Boyette, P.E. Department of Biological and Agricultural Engineering North Carolina State University

Subject: Tobacco Industry Proposal The Flue-Cured Tobacco Industry Leadership Group met this afternoon (2/29/2000) at the NC Farm Bureau offices in Raleigh to further discuss funding of flue cured barn conversions. Immediately following the meeting, a news conference was called by Farm Bureau and others as reported by the Associated Press below:
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Retrofit Tobacco Barns Raleigh-AP -- Tobacco industry groups today announced a pool of 85 million dollars to help farmers pay for refitting curing barns to eliminate a cancer-causing chemical from tobacco.

A coalition including Phiip Morris Inc., the five-state flue cured stabilization cooperative and the farm bureau announced the funding. Farmers this year will be eligible for up to three thousand dollars in grants per barn to change old heating systems to newer heat exchange systems.

A Philip Morris official said the program means his company won't contract individually with farmers this year to grow tobacco. At issue is a compound known as tobacco specific nitrosamines. The chemical compound has been identified as a leading cause of cancer from tobacco smoking.

The chemical is created when heater exhaust is vented through the barn instead of outside it. Farmers in all five flue-cured states will be eligible to apply to the farmers' cooperative for grants. The estimated cost per barn conversion is between five and six thousand dollars.
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The following is the text of a proposal presented to the group by Flue Cured Stabilization. Please note that this proposal was agreed to in principle but may still be subject to minor changes.

Industry Proposal for Cost Sharing the Equipping, Conversion or Purchase of Tobacco Curing Barns to Prevent Combustion Gases from Entering the Curing Chamber

1. This program is designed to provide financial assistance to curing barn operators/owners of up to $3,000 or actual costs, whichever is less who equip curing barns to prevent combustion gases from entering the curing chamber. This conversion must be complete between December 20, 1999 and August 1, 2000. Financial assistance of up to $2,600 or actual costs, whichever is less, will be available to those barn operators/owners who equip or convert barns from August 2, 2000 to June 30, 2001. Payments may be applied toward the purchase of new or used curing barns as to which no payment has been approved or applied for. Notwithstanding the forgoing, the financial assistance to be provided under this agreement shall be limited to barn owner/operator's effective quota (owned or leased) for the 2000 marketing year multiplied by 15› cents per pound.

1.1 Equipment for which payment is received will conform to the guidelines and specifications set forth by the Tobacco Industry Leadership Group under the document known as "Advisory Recommendations for Indirect-Fired Heating Systems for Tobacco Bulk Curing Barns" dated February 14, 2000.

1.2 Definition: Equip, retrofit and convert shall all mean the installation of heating systems in bulk tobacco curing barns which are designed to prevent combustion gases from entering the curing chamber of the barn.

2. The proposed financing program is a fund of $85 million on a contractual cost share basis with the following parties sharing the cost.

2.1 Domestic cigarette manufacturers 2.2 US leaf dealers and exporters

2.3 Stabilization

2.4 Tobacco farmers through additional production costs (fixed and variable)

3. Payments to barn operators/owners who equip barns to prevent combustion gases from entering the curing chamber.

3.1 Owner/operators shall provide receipts, bills etc. as proof of installation for payment and make application for reimbursement upon a form provided by Stabilization and provide producer/owner's total effective quota pounds for the current year.

3.1.1 The qualified equipment installer shall certify upon a form provided by Stabilization that equipment is correctly installed.

3.1.2 Barn operators/owners who install equipment themselves shall certify upon a form provided by Stabilization that any installed equipment will prevent combustion gases from entering the curing chamber.

3.1.3 Any barn operator/owner who accepts payments for barn conversion shall agree to inspection of their barns and installed equipment.

3.1.4 The barn operator/owner shall refund the total payment paid to convert a barn if the tobacco cured in such barn is sold non-auction to a non-participating purchaser within seven years.

3.1.5 The barn operator/owner who submits a false certification to receive funds from this program shall be subject to legal action.

3.2 Upon documentation acceptable to Stabilization, barn operators/owners shall receive payments outlined in 1. Any barn operator/owner who accepts payments for barn conversion(s) shall also agree to the following:

3.2.1 Tobacco shall be cured under approved standards for preventing combustion gases from entering the curing chamber.

3.2.2 All certification for price support eligibility shall be met.

3.3 July 1, 2001 is the proposed FSA certification date for price support eligibility for tobacco cured without exposure to combustion gases. Installation must be complete by this date to receive payments.

4. The parties agree to make no representation or warranties regarding any beneficial effects which may be associated with curing tobacco in barns equipped with devices designed to prevent combustion gases from entering the curing chamber and make no recommendations as to the type of device which a producer/owner may elect to purchase or the method of installation thereof. ***********************************************************************

The Following Report was Compiled by
Mike Boyette and Gerald Peedin - N.C. State University

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The Tobacco Industry Leadership Group subcommittee working on the financing of and standards for retrofitting direct-fired barns with heat exchangers met for the 4th time on the morning of Feb. 14, at the offices of the North Carolina Farm Bureau in Raleigh. After much discussion, the subcommittee agreed on a draft of the "Advisory Recommendations for Indirect-Fired Heating Systems for Tobacco Bulk Curing Barns". The subcommittee subsequently submitted the draft to the full Tobacco Leadership Group at its scheduled meeting on the afternoon of Feb. 14 at the NC Farm Bureau. The full group voted to accept the recommendations as written. The full text of these recommendations is shown below.
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Introduction

Present and ongoing research concerning the production of tobacco specific nitrosamines (TSNAs) in flue-cured tobacco recognize that TSNAs are developed by a multitude of factors during the curing and handling process

(1). This research suggests that one of the most significant factors in the development of TSNAs is the chemical reaction occurring during the curing process between nicotine, contained in the uncured leaf, and various oxides of nitrogen (NOx), which are found in all combustion gases regardless of fuels. The significant reduction or elimination of these nitrogen compounds in the curing air has been shown to substantially reduce TSNAs in cured tobacco

(2). In response to this research, the Flue-Cured Tobacco Leadership Committee has developed these Advisory Recommendations for heating and air handling equipment that may be installed as retrofitted equipment in existing curing barns and as original equipment in new barns. The curing of bright-leaf tobacco by the controlled application of supplemental heat was first developed over 160 years ago. Prior to 40 years ago, tobacco was cured in grower built structures that were heated either with direct-fired (products of combustion freely in contact with the curing leaf) or with some type of indirect-fired (utilizing a heat exchanger or flue) that conducted the products of combustion away from the curing leaf.

Prior to recent research, barns utilizing either direct-fired or indirect-fired systems were considered to be capable of producing cured leaf of excellent and commercially indistinguishable quality. The first commercial tobacco bulk curing barn was sold in 1960. Since that time, it is estimated that more than 60,000 barns have been sold in the flue-cured tobacco producing region of the southeastern US. It is also estimated that no more than 50,000 of these units are still in operating condition.

From 1960 to the mid-1970's, a large portion of all barns manufactured employed oil- fueled, indirect fired heating systems. Many of these barns are still in use. After the mid-1970's, most new barns employed natural or LP gas, direct-fired systems. The reason for this change was the significant equipment cost and maintenance costs differentials between gas and oil fueled equipment. Further, the assumed future availability of gaseous versus liquid fuels and especially the relatively greater efficiency (20 to 40 percent) of direct-fired versus indirect-fired heating systems prompted most growers to purchase LP gas barns. _______________________________________________________

(1) Wahlberg, I., et al., 1999, Tobacco-Specific Nitrosamines: A Multi-Disciplinary Research Area, Agro-Food-Industry Hi-Tech, July/August, pp. 23-28.

Druckery, H. and R. Preussmann, 1962, The Formation of Carcinogenic Nitrosamines in Tobacco, Die Natur., vol. 49: 488-499.

Hecht, S.S., 1998, Biochemistry, Biology and Carcinogenicity of Tobacco Specific N-nitrosamines, Chem. Res. Toxicol., vol. 11(6): 559-603.

Brunnemann, K.D. and D. Hoffmann, 1991, Analytical Studies on N-nitrosamines in Tobacco and Tobacco Smoke, Rec. Adv. Tobacco Science, vol. 17:71-112.

Hecht, S.S. and D. Hoffmann, 1990, The Relevance of Tobacco Specific Nitrosamines to Human Cancer, Cancer Surveys, vol. 8(2): 273-294.

Risner, C.H. and F.N. Wendelboe, 1994, Quantification of Tobacco Specific Nitrosamines in Tobacco, Rec. Adv. Tobacco Science, vol. 38:1-6.

(2) Peele, D.M., D.A. Danehower and G.D. Goins, 1995, Chemical and Biochemical Changes During Flue-Curing, Rec. Adv. Tobacco Science, vol. 21: 82-133.

Peele, D.M., et al., 1999, Formation of Tobacco Specific Nitrosamines in Flue-Cured Tobacco, R.J. Reynolds Tobacco, Winston-Salem, N.C. 27102. ___________________________________________________________________

Recommendations

1. Definitions

1.1. Retrofit. The process and equipment whereby a tobacco curing barn is brought into compliance with these Recommendations.

1.2. Direct Combustion Curing System. A system where the combustion gases are introduced directly into the curing air stream and hence into contact with the curing leaf.

1.3. Indirect Combustion Curing System. A system where the combustion gases are prevented from entering the curing air stream by flues or pipes and the heat is extracted by conduction and forced-convection from a suitable heat exchange apparatus.

1.4. Curing System. The combination of heating and air handling system for curing tobacco including all auxiliary components and controls.

1.5 Heat Exchanger Assembly. Equipment including combustion chambers, flues, pipes, vents, radiators and other associated parts whose function is to contain a burning gas or heated fluid and efficiently transfer the heat to a moving stream of air.

2. General

2.1 These Recommendations are voluntary and are not intended to create an expressed or implied obligation that they be implemented by barn owners or vendors.

2.2 The accepted definitions of "shall" and "should," as included in these Recommendations, are:

2.2.1 "Shall" is intended to indicate actions that would be necessary to support a representation that a barn complies with these Recommendations.

2.2.2 "Should" is intended to indicate that which is advised, but not required, to support a representation that a barn complies with these Recommendations.

2.3 These Recommendations apply to all indirect-fired heating systems and components designed for curing flue-cured tobacco regardless of construction, fuel type or Btu output.

2.4 These Recommendations apply to existing as well as newly constructed barns.

2.5 These Recommendations apply to complete curing systems retrofitted into existing or new manufactured barns as well as heating and/or air handling equipment and components retrofitted into existing barns.

2.6 Portions of these Recommendations that do not relate to control of combustion products apply to tobacco curing systems employing external combustion such as hot water or steam systems as well as electric resistance or other types of systems where fuel combustion does not occur within the confines of the barn and the products of combustion are prevented from entering the barn.

2.7 Direct-fired curing systems of any design or fuel type do not comply with these Recommendations, except as provided under 5.1.

2.8 A curing system that otherwise complies with these Recommendations is not compliant if it has features that impair the results intended by these requirements (i.e., the significant reduction of TSNA's from cured leaf).

2.9 To comply with these Recommendations, equipment shall first comply with all applicable sections of ASAE Standard: ASAE S248.3, latest revision, "Construction and Rating of Equipment for Drying Farm Crops."

2.10 All curing systems, equipment or components complying with these Recommendations shall also comply with any other applicable recommendations, laws, rules, guidelines or codes. A partial list of potentially applicable standards are shown in Attachment A below. Standards other than those shown may also apply.

3. Construction

3.1 Each curing system or component should be constructed of entirely new unused parts and materials.

3.2 The Heat Exchanger Assembly shall be constructed of materials suitable for the intended purpose and of sufficient strength and durability to ensure reliable service for a minimum of three years.

3.3 All equipment shall have all shields, screens and other safety devices for the protection of life and property.

3.4 Provisions shall be made to permit ready observation of and reasonable access to all parts for assembly, maintenance and repair.

3.5 Curing systems shall be designed in such manner as to prevent the products of combustion from entering the curing air in any quantity and in any manner for the warranted life of the system. Means by which combustion gases may enter the curing air include, but are not limited to the following: heat exchanger cracks, weld voids, drafts, improper flue seals, corrosion openings, flame erosion openings and improper mountings.

3.6 Curing systems purporting to comply with these Recommendations shall be subject to tests and examinations by a cooperative tobacco state land grant university program for the levels of nitrous oxides and other combustion gases in the curing air. The same or additional tests of performance, efficiency, reliability and general fitness for the intended application may be conducted by application only from either the equipment manufacturer or barn owner or operator.

3.7 The full results of any test, in writing, will be provided by the testing agency to the persons who requested the test and the equipment owner. Additionally, these test results may be published or otherwise made available to the public through the proper channels of a cooperative tobacco state land grant university program.

4. Applicability

4.1 Barn owners or operators representing that their tobacco is cured in a manner satisfying these Recommendations are responsible for ensuring compliance with these Recommendations.

4.2 To the extent that a vendor of curing equipment, either new air handling and heating systems in new barns, new air handling and heating systems as retrofits to existing barns, or new components as retrofitted equipment to existing barns, represents that it is selling a package compliant with these Recommendations:

4.2.1 The vendor shall ensure that such equipment is compatible with the other components of the barn.

4.2.2 Where systems or components are retrofitted into an existing barn, the vendor shall ensure such equipment meets or exceeds the performance of the original equipment and that the heating and air handling system, in general, likewise meets or exceeds the performance of the original equipment in the original barn in terms of heat output, air handling capacity (i.e., static pressure and flow rate), electrical requirements and general suitability for its intended functions. In particular, and without limitation, a vendor of a retrofitted heat exchanger shall acknowledge and correct for the added air resistance of that heat exchanger if the added resistance reduces the static pressure and flow rate of the existing air handling system to a materially lower level for the proper curing of tobacco.

4.2.3 The vendor shall ensure that equipment complying with these Recommendations shall have little or no effect on the curing schedule in terms of time to complete the cure or the proper control of temperature and humidity as is customarily practiced by the grower with that particular model of barn and tobacco in terms of stalk position, loading capacity or other variables as they arise.

4.2.4 The vendor shall ensure that nothing in the design, installation, maintenance or operation of this equipment negatively impacts the merchantability of the cured leaf removed from these barns.

5. Alternative Systems

5.1 Any barn owner, operator or equipment vendor may nonetheless comply with these Recommendations if it can demonstrate to the satisfaction of (the Agency issuing these Advisory Recommendations) that its barn or process eliminates NOx products or otherwise reduces TSNAs commensurate with a level achieved through compliance with Sections 1-4 of these Recommendations. Attachment A Reference List of Applicable Recommendations The following is a partial list of reference specifications and recommendations pertaining to the design, manufacture, installation, maintenance, testing or use of equipment or potential components for curing tobacco or similar applications.

AMCA 210-67 Standard Tests for Air Moving Devices

ANSI Z83.1 Installation of Gas Piping and Gas Equipment on IndustrialPremises and Certain other Premises

ANSI Z91.1-1972 Performance Standards for Oil-Powered central Furnaces

ASME CSD 1-1995 Control and Safety Devices for Automatically Fired Boilers

ASAE S248.3 Construction and Rating of Equipment for Drying Farm Crops

CAN/CGA-3.8-M86 Gas-Fired Equipment for Drying farm Crops ISO 65.160 Standards for Tobacco, Tobacco Products and Related Equipment.

NFPA No. 31 Standards for Installation for Oil Burning Equipment

NFPA No. 54 Standards for Installation for Gas Appliances and Gas Piping

UL 296 Standards for Oil Burners

UL 731 Oil-Fired Heaters

UL 795 Commercial Industrial Gas Heating Equipment *************************************************************************