Min-k (Johns-Manville): asbestos content and history

Min-K was a Johns-Manville insulation, made as molded sheets and panels and, from 1961, in a flexible form.^1,2 When J-M disclosed it in April 1958, Asbestos, the industry's trade journal, reported the company's description: a non-metallic, inorganic material "composed of silica, asbestos 'and other materials,'" that could withstand a "constant" temperature of about 1,300 degrees Fahrenheit.³ J-M was then making it at a pilot plant in Manville, New Jersey, and supplying it to the Government for use in at least one operational missile.³

When and where it was made

A 1990 EPA notice that published what Manville reported says the molded Min-K grades (1301, 2000 and 500, and Min-Klad) and the flexible blankets were produced from 1958 to 1974.⁴ An insurance company's 1981 list of asbestos products, compiled from other companies' answers in lawsuits, gives Min-K, listed as paper, felt and blankets, as made from 1963 to 1974.⁵ In 1967 J-M's employee magazine said Min-K was made in the Industrial Insulations Plant at Manville, and a 1970 J-M notice lists Min-K 500, 1301 and 2000, Min-Klad, and three flexible Min-K products under the Manville plant.^6,7 A 1970 J-M audit records workers pressing 36 by 36 by 1/4 inch standard Min-K panels.⁸

What it was made of

The 1990 notice gives the Min-K products 5 to 20 percent asbestos fiber and 70 to 80 percent colloidal silica, with up to 20 percent titanium dioxide and up to 6 percent phenol-formaldehyde resin among the other ingredients.⁴ J-M's employee magazine called it in 1967 "a molded fibrous material reinforced with asbestos."⁶ The flexible form was Min-K stitched between two faces of glass cloth, as a blanket or tape, recommended up to 1400°F in steady use; a 1966 article describes it as Min-K enclosed in heat-resistant silica cloth.^2,9

Where it was used

In 1959 Asbestos magazine reported Min-K, which it called one of the two asbestos products used, on a heated molten-sulphur pipeline from Freeport Sulphur's Grand Isle offshore mine.¹⁰ J-M's employee magazine said Min-K flew on the Mercury and Gemini flights and insulated Apollo fuel cells, and that a new flexible formulation, number 1301, protected a NASA capsule's instruments during re-entry in 1964.^9,11 In 1967 it reported Min-K supplied in molded sheets to Lockheed, which cut it on a band saw for jet airliner flight recorders.⁶ On Apollo 11 in 1969, Asbestos magazine wrote, Min-K insulated the S-band antenna gimbal, the Command Module windows, the Service Module fuel cells and the Lunar Module descent stage.¹²

Asbestos claims

If you or a family member worked with or around Min-k (Johns-Manville) and later developed mesothelioma or another asbestos disease, a claim may be paid by the Manville Personal Injury Settlement Trust. Free case review.

What each document says

Every statement about Min-k (Johns-Manville) in the documents, in each document's own words.

The Borel v. Fibreboard Case File (1969-1972), Answers to interrogatories with exhibits

Description: “(Molded Insulation) A molded fibrous insulating material.”, p. 26¹

Asbestos Magazine, 1961, April 1961

Form: “Flexible Min-K is available in blanket or tape form stitched between two faces of glass cloth”, said by Johns-Manville Corporation, as recorded by Asbestos (magazine), p. 20²
Temperature limit: “recommended for steady state applications up to 1400°F, and higher for transient conditions”, said by Johns-Manville Corporation, as recorded by Asbestos (magazine), p. 20²

Asbestos Magazine, 1958, April 1958

Asbestos content: “composed of silica, asbestos "and other materials"”, said by Johns-Manville Corporation, as recorded by Asbestos (magazine), p. 14³
Made at: “a pilot plant in Manville, N. J.” (the plant: Manville, New Jersey), said by Johns-Manville Corporation, as recorded by Asbestos (magazine), p. 14³
Use: “insulating vital parts of missiles”, said by Johns-Manville Corporation, as recorded by Asbestos (magazine), p. 14³
Sold from: “supplying the Government with quantities of a new insulating material” (sales to U.S. Government), said by Johns-Manville Corporation, as recorded by Asbestos (magazine), p. 14³
Temperature limit: “"constant" temperature of about 1,300 degrees Fahrenheit”, said by Johns-Manville Corporation, as recorded by Asbestos (magazine), p. 14³

Asbestos; Publication of Identifying Information (1990)

Made from: “produced 1958”, said by Manville Corporation, as recorded by U.S. EPA, Federal Register 55 FR (Feb. 13, 1990), p. 14⁴
Asbestos content: “asbestos fiber, 5 to 20%”, said by Manville Corporation, as recorded by U.S. EPA, Federal Register 55 FR (Feb. 13, 1990), p. 14⁴
Ingredient: “titanium dioxide, 0 to 20%”, said by Manville Corporation, as recorded by U.S. EPA, Federal Register 55 FR (Feb. 13, 1990), p. 14⁴
Ingredient: “phenol-formaldehyde resin, 0 to 6%”, said by Manville Corporation, as recorded by U.S. EPA, Federal Register 55 FR (Feb. 13, 1990), p. 14⁴
Ingredient: “colloidal silica, 70 to 80%”, said by Manville Corporation, as recorded by U.S. EPA, Federal Register 55 FR (Feb. 13, 1990), p. 14⁴
Made until: “to 1974”, said by Manville Corporation, as recorded by U.S. EPA, Federal Register 55 FR (Feb. 13, 1990), p. 14⁴

The Travelers Insurance Company's Product Information Booklet for Its Asbestos Seminar (1980–1981)

Made from: “63”, p. 6⁵
Made until: “74”, p. 6⁵
Form: “PAPER,FELT,BLANKETS”, p. 6⁵

J-M News Pictorial, 1967, April 1967

Use: “jet airliner flight recorders” (sales to Lockheed Aircraft Service Company), p. 3⁶
Made at: “the Industrial Insulations Plant at Manville, N. J.” (the plant: Manville, New Jersey), p. 3⁶
Asbestos content: “a molded fibrous material reinforced with asbestos”, p. 3⁶

M. W. Burleson's Notice to the Industrial Insulations Division on Health Hazard Caution Labels (1970)

Warning label: “Min-K - 500, Min-K - 1301, Min-K - 2000, Min-Klad, Std. Flexible Min-K, H.T. Flexible Min-K, Flexible Min-K Tape (label L-4955)”, p. 2⁷
Made at: “Manville Plant” (the plant: Manville, New Jersey), p. 2⁷

Johns-Manville Audit of the Incentive Standard for Pressing Flexible Min-K Panels (1970)

Form: “36 x 36 x 1/4 STD MIN K Panels”, p. 1⁸

J-M News Pictorial, 1966, June 1966

Use: “used on both the Mercury and Gemini flights; Apollo fuel cells and LEM heat shield” (sales to NASA (Project Apollo)), p. 4⁹
Description: “Flexible Min-K, which is Min-K insulation enclosed in a heat-resistant silica cloth”, p. 4⁹

Asbestos Magazine, 1959, July 1959

Use: “heated molten-sulphur pipeline from Freeport Sulphur's Grand Isle offshore mine” (sales to Freeport Sulphur Company (Grand Isle, Louisiana)), p. 26¹⁰
Asbestos content: “one of the two asbestos products used is Min-K”, p. 26¹⁰

J-M News Pictorial, 1964, September 1964

Change: “a new formulation of Flexible Min-K—designated number 1301”, p. 5¹¹

Asbestos Magazine, 1969, December 1969

Use: “Apollo 11: S-band antenna gimbal, Command Module windows, Service Module fuel cells, Lunar Module descent stage” (sales to NASA (Apollo 11)), p. 34¹²

Manville Fund's Answers to Interrogatories in Gunn v. Celotex (1989)

Made from: “Date Manufactured: 1963”, p. 112¹³
Warning label: “Date Labeled: 1970”, p. 112¹³
Asbestos content: “asbestos containing”, p. 62¹³
Use: “designed principally for use on rockets, missiles, and jet aircraft”, p. 70¹³
Asbestos content: “20.0 % fiber by weight”, p. 112¹³
Made at: “Manville Plant, Manville, New Jersey (1913 through 1985): Flexible Min-K” (at Manville) (the plant: Manville, New Jersey), p. 62¹³
Asbestos fiber: “Amosite”, p. 112¹³
Description: “A fibrous insulating material ... can withstand high heat and has an extremely low thermal conductivity”, p. 70¹³
Made until: “Date Discontinued: 1975”, p. 112¹³
Form: “Sheet”, p. 112¹³

Manville Fund's Responses to Plaintiffs' Interrogatories in Moore v. H.K. Porter (1990)

Change: “Flexible MIN-K (High Temperature Std.) replaced by non-asbestos Flexible MIN-K (High Temperature Std.), 1973/77”, p. 18¹⁴
Asbestos content: “asbestos containing (thermal insulation product)”, p. 18¹⁴
Made at: “Manville Plant (1913 to 1985): Flexible Min-K” (at Manville) (the plant: Manville, New Jersey), p. 22¹⁴

E. M. Fenner to D. B. Wingerter on Which Insulation Products to Label (1969)

Warning label: “in a "grey" area, and would need individual review”, p. 1¹⁵

The Potter v. Fibreboard Case File (1969-1972), Answers to plaintiff's interrogatories with exhibits

Description: “(Molded Insulation) A molded fibrous insulating material”, p. 26¹⁶

Kind of product

We list Min-k (Johns-Manville) with asbestos-cement pipe, board and sheet, paper, felt and millboard and cloth, tape and other textiles, from how the documents describe its form. Those pages explain how such products exposed workers.

Trades that worked with products like it: Carpenters and Construction Workers.

References

The Borel v. Fibreboard Case File (1969-1972), Answers to interrogatories with exhibits (March 27, 1970), p. 26.
Asbestos Magazine, 1961, April 1961 (April 1, 1961), p. 20.
Asbestos Magazine, 1958, April 1958 (April 1, 1958), p. 14.
Asbestos; Publication of Identifying Information (February 13, 1990), p. 14.
The Travelers Insurance Company's Product Information Booklet for Its Asbestos Seminar (1980–1981) (April 30, 1981), p. 6.
J-M News Pictorial, 1967, April 1967 (April 1, 1967), p. 3.
M. W. Burleson's Notice to the Industrial Insulations Division on Health Hazard Caution Labels (July 1, 1970), p. 2.
Johns-Manville Audit of the Incentive Standard for Pressing Flexible Min-K Panels (May 7, 1970), p. 1.
J-M News Pictorial, 1966, June 1966 (June 1, 1966), p. 4.
Asbestos Magazine, 1959, July 1959 (July 1, 1959), p. 26.
J-M News Pictorial, 1964, September 1964 (September 1, 1964), p. 5.
Asbestos Magazine, 1969, December 1969 (December 1, 1969), p. 34.
Manville Fund's Answers to Interrogatories in Gunn v. Celotex (December 7, 1989), p. 112.
Manville Fund's Responses to Plaintiffs' Interrogatories in Moore v. H.K. Porter (February 15, 1990), p. 18.
E. M. Fenner to D. B. Wingerter on Which Insulation Products to Label (August 7, 1969), p. 1.
The Potter v. Fibreboard Case File (1969-1972), Answers to plaintiff's interrogatories with exhibits (December 29, 1969), p. 26.

This page is provided for general informational purposes and does not constitute legal advice. Every asbestos case turns on its own facts, exposure history, diagnosis, deadlines, available evidence, and applicable law. Reviewing this page does not create an attorney-client relationship. For advice about your specific situation, call 833-4-ASBESTOS for a free case review.

Min-k (Johns-Manville)