Gases and welding products manufacturer Afrox Self-Rescue Division has secured an order to deliver 26 500 units of AfroxPac 35i self-contained self-rescuers and accessories in a deal valued at R70-million, which will be supplied over the next five months.

Afrox manager Peter Rowlands tells Mining Weekly that the order from a leading local platinum producer, goes well beyond producing and delivering the 26 500 units. The mine also requires individual storage racks for each unit and is obliged to train all users in their proper handling and use.

“Afrox has provided 140 multirack storage frames and training and simulation equipment and is currently training the mine’s trainers and lamp-room personnel. Afrox is also represented on the mine’s implementation project committee that meets weekly to oversee the deployment and roll-out of the self-rescuers,” says Rowlands.

He states that Afrox secured the tender in August and finalised the order in November last year. “Despite a very tight deadline, the first 6 000 units, capable of providing life-saving oxygen to underground personnel in the event of an underground fire or exposure to toxic gases, were delivered in December.

“AfroxPac is one of the few mining-equipment items that is expected to be carried daily, while attached to the body, for use in the most severe conditions, for up to ten years. However, it must still have the life-saving function of a new unit. Because the oxygen is generated from a chemical reaction, there is no need to carry cylinders of compressed air, making the devices relatively compact and light,” says Rowlands.

He mentions that an AfroxPac can be carried for 15 000 hours to 20 000 hours during its life span and that current stock are cumulatively used underground for well over a million worker hours every day.

“AfroxPacs comprise more than 70% of the South African self-rescuer market and are represented in significant quantities across virtually all the hard-rock underground mining groups, such as Lonmin, Impala Platinum, AngloGold Ashanti, Gold Fields, Anglo Platinum, Northam, Samancor, Xstrata, Aquarius and Petra. The devices are widely used in underground coal operations and in many mines in Zimbabwe, Botswana and Zambia,” Rowlands points out.

The AfroxPac 35i is an upgraded model of the AfroxPac 35. The average breathing duration of the AfroxPac 35 has been shown in independent testing by the Council for Scientific and Industrial Research over ten years of deployment to comfortably exceed the rated duration. This gives customers confidence when considering a significant capital and safety investment.

The AfroxPac 35i body-worn self-contained self-rescuer is the latest-generation unit, representing three years of development and testing, which culminated in achieving SANS 1737:2008 compliance. The self-rescuer has been developed in close association with the South African mining industry and is 100% locally manufactured and supported, having been tested under some of the toughest mining conditions in the world, states Afrox.

“In moving to smaller and lighter battery packs, our customers would appreciate a smaller and lighter self-rescuer and the challenge is to develop such a device without sacrificing its breathing duration capacity. However, the AfroxPac 35i remains one of the most compact of the currently approved units.

“South African regulations require that any self-contained self-rescuer must be compliant with SANS 1737:2008. Other countries have their own standards, most of which are based quite strongly on the European EN 13794:2002 standard, but with added requirements for local conditions. In the development of the SANS 1737:2008 test protocol, the typical South African low hard-rock environment was taken into consideration, where the constricted space leads to inevitable bumping and grinding of body-worn equipment such as a self-rescuers,” he explains.

Further consideration was also given to the effect of subjecting the units to the constant vibration of underground vehicles such as load-haul-dump vehicles. As a result, very stringent conditions were added to the tests under the standard, where several test units were exposed to thousands of sequential-vibration, drop, tumbling, abrasion and crushing events. These events were all designed to pulverise the oxygen-generating chemical before the units were subjected to the breathing simulator and in-person tests.

“This is an exceptionally rigorous standard and achieving compliance with the latest-amendment SANS 1737:2008 is a significant milestone for the AfroxPac 35i,” states Rowlands.

Basic use and care of the AfroxPac 35i are simple, but critical for a life-saving device. The Afrox Self-Rescue Division provides on-site instruction to the mine trainers so that they can incorporate the skills into the mine’s training programme.

“We also provide training in the care and maintenance of the units for the lamp-room staff who are responsible for storing and issuing the units. Typically, the training takes two to three hours, followed by a written and practical assessment, as well as a yearly reassessment,” he says.

Afrox concludes that currently, its research and development team is developing a long-duration breathing device, which will undergo testing in Europe against the Euro- pean safety standards. Other areas of development include alternative materials to further improve durability and longevity, and adaptations to enter the markets that have specific local self-rescuer requirements.