Mastic & Foams | Astro LST Mastic

>Trade Name: Astro LST Mastic

Low Smoke & Toxicity Intumescent Mastic Sealant

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Low Smoke and Toxicity Intumescent Mastic Sealant
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Astro LST Mastic

> Quick Overview


Telephone Astroflame 01329 844 500

Email Astroflame

Fax Astroflame 01329 844 600

PDF Data Sheets Download PDF Data Sheets

For in-stock items orders received before 2pm (Monday-Friday) are generally dispatched for delivery on the following working day (Monday-Friday).

> Product Description

A one water based acrylic sealant designed to resist the passage of fire, by forming a char that prevents the passage of fire and smoke, while maintaining excellent low smoke and toxicity levels.

Astro LST Mastic is halogen free and does not emit halogenated by-products under fire conditions.

High performance fire resistance rating with joint movement capabilities.

Highly flexible and it has good unprimed adhesion to a wide variety of common building substrates.

Tested in Block Wall, Concrete, Masonry and Plasterboard Partition. Tested in Concrete Floors.

Tested in gaps up to 60mm wide.

In normal use it maintains the sound reduction index of a structure.

Mould Resistant.

This sealant contains no raw materials known to have an estrogenic effect in the environment.

> Properties

General Characteristics Inspection Method Value
Product Data (uncured)
Density (S.G) ASTM D792:13 1.63
Appearance Paste, matt finish
Resistance to flow ISO 7390 : 2003 Pass
Product Data (after curing)
Hardness Shore A ISO 7619-1 : 2010 63/39
Operating Temperature °C -5 to 40
Loss Mass of Mass on Heating ISO 3451-1 (Method A) 68.34
Flexibility - Bend Test ISO 1519 Pass
Longevity of Firestop Materials ASTM E2923 : 14 30 Years
Conditioning EOTA TR024 Type X

Astro LST Mastic is not affected by an outdoor environment. However, for long term storage and ease of installation, it is recommended that it should be stored indoors ideally in dry frost free conditions above 0°C and below +30°C.

> Product Availability

The Astro LST Mastic Comes Only in White.

Product Code Product Description Size
AFIMLST Astro LST Mastic White 310ml

> To Order & Specify

Please contact us and quote the following information - Quantity / Product Code / Product Description / sizes
Typical wording- 10 / AFIMLST / Astro LST Mastic / 310ml

>> Tel: 01329 844 500 or >> Email:

> Installation

For further information on installation requirements please contact the technical team on: tel 01329 844 500 or email

> Health and Safety

The product does not present any known health hazards during or after installation. Normal good industrial and personal hygiene practices should be observed. For further information on health and safety requirements please contact the technical team on: tel 01329 844 500 or email

> Data Sheet Downloads

Download and review the following available data sheets for this product.

Key Information:
  • PDS's are Product Data Sheets
  • SDS's are Safety Data Sheets
  • TDS's are Technical Data Sheets
  • INT's are Install Data Sheets
  • VID's are Video Files
  • DoP's are Declaration of Performance
  • CoC's are Certificate of Constancy of Performance
  • ETA's are European Technical Assessment Sheet
  • UL Documentation are UL - EU Certificate

> Delivery/Returns

For in-stock items orders received before 2pm (Monday-Friday) are generally dispatched for delivery on the following working day (Monday-Friday). All dates quoted for despatch are estimates only and are not guaranteed. We will endeavour to meet these dates but shall have no liability for any delay in despatch or delivery or any damage or loss occasioned thereby. We may deliver products pursuant to any order by instalments. If we are unable to deliver the goods for any reason,you will be contacted and you will not be obliged to pay for the goods which have not been delivered, you also have the option to cancel the goods that have been delivered, however we shall not be liable for any loss of income or profit which may have been caused by the delay or non delivery of goods.

For information about our returns policy please click here.

> Ask a Question

If you've got a question about this product or need some technical help get in touch with the Astroflame sales or technical team to discuss your requirements today. We are open Monday to Friday 8:00am to 5:30pm. You can always contact us on the following:

T: 01329 844 500


F: 01329 844 600

Web Page Last Modified: 09.07.2020 13:06

Data Sheets Downloads

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