Р-70i DEZEGA
6
2. PURPOSE, DESIGN AND OPERATION PRINCIPLES
OF THE BREATHING APPARATUS
The breathing apparatus is designed to protect the user’s respiratory system from the harmful
effects of respiration in an IDLH (immediately dangerous for life and health) atmosphere during
the performance of mine rescue, emergency rescue, and technical operations in coal mines, tunnels
and other industrial facilities.
The breathing apparatus ensures reliable protection of the human respiratory system in an atmosphere
that contains insucient oxygen or contains toxic gases and coal dust. It’s designed for operation at
an air temperature of minus 6 °C to plus 60 °C (it is allowed to operate the breathing apparatus at the
temperature of minus 20 °C, but when donning the temperature should not be below 10 °C), relative
humidity of up to 100 % and atmospheric pressure of 70-125 kPa.
The breathing apparatus is a self-contained device that supplies pure oxygen. The breathing gas
mixture circulates in a closed respiratory circuit. Soda-lime CO2absorber absorbs carbon dioxide
contained in a mixture of gases exhaled by the user. In the breathing bags, the gas mixture is
enriched with oxygen from an oxygen cylinder. At low and normal respiration frequency (resting state,
walking at a normal rate), oxygen is supplied to the breathing system only through a constant flow
dosing valve. At an increased breathing frequency, an additional amount of oxygen is fed through
the demand valve or the manual bypass valve. The breathing mixture heated by the regeneration
reaction and cools down in the separator and cooler. In order to reduce the temperature of the
inhaled gas mixture and thereby minimize the user’s discomfort and as well as during work at an
elevated ambient temperature, the cooling elements (water ice cube) are placed into the cooler of
the breathing apparatus.
The breathing apparatus is also equipped with electronic measuring device (EMD) that signals that
the cylinder valve is closed or that there is no oxygen in the system the cylinder pressure drops below
minimum set pressure. This device also has a number of additional information-related features,
which are described below.
The model of breathing apparatus may also be equipped with connecting device based on
medium-pressure between breathing apparatuses, which is available as an option for the customers.
3. TECHNICAL DATA
Nominal working duration, NWD, hours 2
Eective working duration, EWD, hours 2,5
Oxygen cylinder capacity, dm31,8
Pressure in the oxygen cylinder, MPa 20
Continuous oxygen supply, dm3/min 1,8±0,2
Oxygen capacity, not less dm3360
Weight of the soda lime CO2absorber, not less, kg 2,3
Weight of an equipped breathing apparatus, kg 13
Demand valve opening pressure, Pa ≥ 0
Relief valve opening pressure, Pa ≤1000
Breathing apparatus dimensions (DxWxH), mm (582х403х175)±3
