1. The breathing apparatus set should be a self-contained, compressed air breathing apparatus of open circuit with automatic positive pressure. 2. The scba shall consist of all the main parts and necessary accessories, including a) face mask assembly b) air regulation and supply assembly c) back plate assembly with harness d) cylinder with straps (carbon composites with aluminum alloy liner) e) pressure gauge 3. The apparatus shall be sufficiently robust to withstand rough usage that a fire-fighting situation might demand. All the materials used in the construction shall have adequate mechanical strength and shall be fire-resistant and water resistant. 4. The design and construction of the apparatus shall be such as to facilitate easy dismantling and reassembling of the parts. Ba set shall be confirming to is:10245 (part-2)/en 136 and 137 type 2. 5. The demand valve should automatically turn on the positive pressure on first breathing. At the same time there should be provision for manually activating the positive pressure or to inject extra air into the mask. There should be provision for adequate positive pressure within the mask during the entire breathing cycle to prevent leakage of ambient toxins into the facemask. 6. The scba should have an effective warning system to indicate and alert the persons wearing the scba, ten minutes in advance about the diminishing air available for him. The warning sound should stop only when the air in the cylinder is completely used up. 7. The harness assembly should be comfortable with shoulder pads and waist belt with self – luminous patches should be adjustable. 8. The pressure reducer should be of a suitable type and should deliver a constant & steady pressure throughout the duration irrespective of the cylinder pressure. 9. The pressure gauge should be phosphorescent for easy reading during dark hours and should have markings starting from 0 and going to a value of pressure higher than the pressure of the cylinder offered and giving enough space for the pointer to vacillate. The warning zone in the pressure gauge should be shown in a contrasting color. 10. The cylinder should be seamless and should have filling rate of 6 litres capacity and an optimum pressure of 300 bars. 11 the scba set must be supplied with suitable and strong carrying case with locking facility. 12. The complete set should have approval as per the provisions of bis or an equivalent internationally accepted standard.