"The significant aspect of this layout is the absence of
backfill. In addition, the up-cast ventilation travels against
the flow of rock and spent service water as it travels upwards
from the inlet towards the face. This contact may be
extensive and may be of the order of 200 m for newly
established stopes. The velocity however is high, reducing
the effect of temperature and humidity change but possibly
increasing the dust levels in the air. Ventilation control is
somewhat difficult as faces are underhand and there is no
backfill making it difficult to channel air flow close to the
face11. Once the air reaches the **stoping panels,** it absorbs
contaminants very quickly and is released to the upper levels where only limited travelling takes place. If the air is to be reused it would need to be removed from the reef horizon as
close to the panels as possible (next level) and re-conditioned
before being used in another production block.
Generally this** stoping*** approach has relatively high
ventilation needs per ton and the in-stope heat loads per ton
can be relatively high particularly if the (unfilled) worked
area is considered to be within the air-conditioned zone.

https://www.vuma3d.com/wp-content/uploads/2021/04/Variations...


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Note added at 2 days 11 hrs (2024-03-09 02:06:07 GMT)
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Ventilation Controls

Both through ventilation and auxiliary fan and duct systems are used to provide ventilation air to locations where personnel may work. Ventilation controls are used to direct the air to the working place and to minimize the short circuiting or loss of air between intake and exhaust airways.
voir a https://www.iloencyclopaedia.org/part-xi-36283/mining-and-qu...

A bulkhead is used to stop air flowing through a connecting tunnel. The materials of construction will depend on the pressure difference and whether it will be subject to shock waves from blasting.**** Flexible curtains (je pens STOPING PANEL)*** attached to the surrounding rock surfaces are suitable for low pressure applications
such as separating the **intake and return airways ***in a ***room-and-pillar panel** mined with a continuous miner. Timber and concrete bulkheads are suitable for higher pressure applications and may incorporate a heavy rubber flap which can open to minimize any blast damage.

en plusier de llangue, version francaise... Une cloison est utilisée pour empêcher l'air de circuler dans un tunnel de liaison. Les matériaux de construction dépendront de la différence de pression et s'il sera soumis aux ondes de choc du dynamitage.*** Les rideaux flexibles*** attachés aux surfaces rocheuses environnantes conviennent aux applications à basse pression telles que la séparation des voies d'air d'admission et de retour dans un panneau à** chambres (stope)*** et piliers exploité avec un mineur cont

inu. Les cloisons en bois et en béton conviennent aux applications à haute pression et peuvent incorporer un volet en caoutchouc lourd qui peut s'ouvrir pour minimiser les dommages causés par le souffle.

passage in anglais , PANEL, Aux niveaux supérieurs de certains systèmes d'abattage à ciel ouvert, un accès peu fréquent à travers les régulateurs peut être nécessaire et des ***panneaux flexibles*** renforcés horizontalement peuvent être simplement relevés ou abaissés pour fournir un accès tout en minimisant les dommages causés par le souffle. Même des tas de roches brisées ont été utilisés pour augmenter la résistance dans des sections d'un niveau où il n'y a temporairement aucune activité minière.