BS EN 60079-13-2017 pdf free download.Explosive atmospheres Part 13: Equipment protection by pressurized room “p” and artificially ventilated room “v” (IEC 60079-13:2017)
4.3 Construction
The protected room shall , at a minimum , be designed to allow pressurization or artificial ventilation to be used in accordance with Clauses 6 or 7.
NOTE T he room construction re qu ireme nts could be affected by the location , occupancy requi rements , and fu nct i ona li ty For pressurized rooms and rooms protected by artificial ventilation , provision shall be made to ensure adequate purging of dead air spaces created within the room , for example by avoiding suspended ceilings , trenches , or raised floors.
4.4 Mechanical strength
The room and any ducts and their connecting parts designed to withstand the maximum pressure of the pressurization or ventilation system. This verified by the design documentation or by the overpressure test of 6.4.2. National or regional building requirements may also apply. Test for mechanical strength need not be carried out on the completed room but may instead be applied to all parts such as windows , gland plates , penetrations , doors , inlets or outlets of the room which are not made of steel or concrete but which are integral to the type of protection. In this case , the tests may be carried out on the parts themselves , appropriately mounted for the tes t.
4.5 Penetrations and seals
The entry of cables , electrical conduits and other penetrations into the room shall be sealed so that the necessary pressure differential or artificial ventilation integrity is maintained. Measures shall be taken to minimize the exchange of atmosphere between the inside and the outside of the room where this may lead to another hazard , for example displacement of vapours via floor drainage facilities. Barriers may need to be considered for certain room designs to minimize ingress or egress of gases or vapours , for example this may include liquid seals such as s-bends in drain piping.
4.6 Personnel access doors
Where protection against ingress of a flammable atmosphere is required , doors for personnel access shall be automatically self-closing , close fitting , and designed to close and latch against the normal pressure differentia l. Restricted access doors are not required to be self- closing. NOTE Refer to IEC 60079 -1 0- 1 f or addi tiona l guidance on doors.
4.7 Inlets and outlets
For pressurization and general artificial ventilation , the location of air inlets and outlets shall be arranged to ensure even distribution of the clean air flow to minimize pockets where gases or vapours could accumulate , taking into account the density of those gases and vapours. Verification shall be according to 6 .4.4 or 7.5.3. Where it is not possible to avoid pockets where gases and vapours can accumulate , alternative methods of detection and control shall be used .
4.8 Ducts
In order to minimize the entry of contaminated air in the duct or loss of system performance , the fan suction and discharge ducts should be suitably designed to be free of leaks and protected against foreseeable mechanical damage . NOTE D uc ts for the pressurizalion system or vent il ation system can be subject 10 app l icab le national or reg ion al standards for bui l ding fi re requ ir ements .
4.9 Purging and cleaning
4.9.1 General
Purging of flammable gases or removal of combustible dusts from a pressurized room or an artificially ventilated room is required at both the initial commissioning of the room and following loss of pressurization or loss of flow, respectively. Administrative procedures or other controls during loss of pressurization or artificial ventilation may be deemed by the user sufficient to ensure a gas free atmosphere under some conditions, for example during short time loss of pressurization or artificial ventilation and when no other abnormal situations are present. However, the means for purging shall still be provided.BS EN 60079-13 pdf download.