Gas curtains

[Waggoner]

I understand that these were used to prevent gas from seeping into dugouts, etc. Does anyone know how they were made, what they were made of and how they looked? We want to make some replica ones for a new trench exhibit and want to be as accurate as possible.

All the best,

Gary

[centurion]

In this case some form of moistened blanket

[Waggoner]

Centurion,

Thank you! I suppose that there were other configurations as well? Presumably made from local materials vice specially manufactured fabric?

All the best,

Gary

[Chris Henschke]

These instructions are from 1 ANZAC Corps Duties of Anti-Gas Personnel and Instructions for protection of Dug-outs against Gas, printed in June 1917.

Diagram from same publication.

[Waggoner]

Chris,

Thank you for this additional information! It appears that using a blanket is the way to go.

All the best,

Gary

[centurion]

Chris,

Thank you for this additional information! It appears that using a blanket is the way to go.

All the best,

Gary

A bit more complex than that See this extract from a US document C1919 see the bit I've highlighted

Dugout Blankets.

Dugout protection is intended to prevent entrance of any gases, lethal, lachrymatory or irritant, into the enclosed space.

This has been most efficiently accomplished by means of curtains hung upon wooden frames and fitting closely against all edges of the opening to be closed. These curtains have usually been of heavy material and have generally been spoken of as dugout blankets. Since they were designed to exclude all toxic gases, they had to be devised upon general mechanical principles rather than upon principles of chemical action with specific gases. Permeability to air has not been considered a necessity, it being held that sufficient ventilation is secured by means of the air entering through the soil. For large dugouts or extended use large air filters were designed to draw pure air into the dugout with a fan.

The qualities aimed at, to which both fabric and treatment should contribute, are the following:

(a) Impermeability to gas.

(b ) Flexibility, especially at low temperatures,

© Non-inflammability.

(d )Freedom from stickiness and from tendency to lose material by drainage under action of gravity.

(e) Mechanical strength.

(f) Simplicity of manufacture and treatment.

(g) Low cost.

Army blankets, both those for men and those for horses, proved suitable materials for curtains, but the scarcity of wool made it desirable to select an all cotton fabric.

A large number of oils were studied as impregnating agents. The most satisfactory mixture consisted of 85 percent of a heavy steam refined cylinder oil and 15 per cent of linseed oil. This is taken up to the extent of about 300 per cent increase in weight of the blanket during impregnation. It becomes oxidized to some extent upon the surface of the blanket, other than the soft, central core. The finished blanket possessed the following properties:

It resists penetration of 400-600 p.p.m. of chloropicrin for 8 hours (dugout test) and mustard gas for 100-400 minutes (machine test).

It is sufficiently flexible after standing for 2 hours at 18 F. to unroll of its own weight, and may be unrolled by applying a slight force at 6 F.

it is not ignited by lighted matches and shows but little loss by drainage.

Two types of machines were designed for impregnation, one for use on large scale behind the line, and a field apparatus for use at the front.

[Waggoner]

Centurion,

Thank you again!

All the best,

Gary