Can positive pressure air respirators be used underwater/Where can I buy them in Yancheng?

) Song Dynasty) Scope of application:
) Song Dynasty) Positive pressure air respirators are suitable for use by firefighters or emergency rescue personnel in toxic or harmful gas environments, containing harmful substances such as smoke and dust, and environments lacking oxygen. , providing users with effective respiratory protection. Widely used in fire protection, electric power, chemical industry, shipbuilding, smelting, warehouses, laboratories, mining and other departments. < Execution standards: < "Positive Pressure Fire Air Respirator"
) Song Dynasty) Main features:
) Song Dynasty) & adopts a new wide field of view full face mask, anti-fog, anti-dazzle, wide field of view, airtight Good performance and comfortable to wear. < &The air supply valve has small size, large air supply capacity, reliable performance, and does not affect the field of vision during use. <&The back panel is made of carbon fiber composite material, which is light weight and high strength. It has fixed pipeline grooves to effectively prevent climbing. Ergonomically designed, more comfortable and convenient to wear. <&Adopts a new type of pressure reducer, which is small and compact in size, has a built-in safety valve, has reliable performance, does not have any adjustment device, and is maintenance-free. It is equipped with a spare interface, and other rescue connectors or external air sources can be installed as needed. <&The pressure gauge is waterproof, shockproof, and has luminous display functions. The residual pressure alarm is small in size, light in weight, and the alarm is accurate and loud. <&The bottle valve is equipped with a ratchet check device to prevent it from being closed accidentally during use. The bottle valve with a pressure display is optional, which can also display the gas storage pressure in the bottle when the valve is closed. <&The same set of back plates and carbon fiber composite cylinders can be replaced at will.
) Song font) Main technical parameters:
) Song font) Serial number, technical parameters, specifications, model./(.)&R./(.)./(.)&/(.&) c=c>< br/>< Overall weight c=c>
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< Residual air alarm pressure ~ c=c>
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< Carbon dioxide content % in inhaled gas