AS NZS 60079.5:2015 pdf free.Explosive atmospheres Part 5: Equipment protection by powdered filling ‘q’.
4.1.1.3 Containers intended to be opened for repair
Electrical equipment, parts of electrical equipment, or Ex components that are designed to be repaired shall incorporate sealing methods that are capable of being renewed without damage to the container when the equipment is repaired, re-filled, and re-sealed. The container shall be marked in accordance with Clause 6, item b).
4.1.2 Pressure test of container
The electrical equipment, parts of electrical equipment or Ex components protected by powder filling q” shall meet the pressure test requirements specified in 5.1.1.
4.1.3 Degree of protection of the container
The container of the electrical equipment, parts of electrical equipment, or Ex components protected by powder filling “q”, in their normal service condition, i.e. with all openings closed as in normal use, shall comply at least with the degree of protection lP54 as defined in IEC 60529. If the degree of protection is 1P55 or higher, and the container is not hermetically sealed, the container shall be provided with a breathing device. The container with the breathing device in place shall comply at least with the degree of protection lP54 according to IEC 60529. The test shall be conducted on an empty container without the powder filling installed. At the end of any water ingress tests, no water shall be visible inside the container.
NOTE 1 As the container may need to be destroyed in order to determine the entrance of dust or water, two separate test samples could be required for the two ingress tests.
NOTE 2 When the container is also the external enclosure, the tests of enclosures requirements of IEC 60079-0 apply.
The ingress protection of containers or parts of electrical equipment protected by powder filling Mq”, intended for use only in clean, dry rooms, may be reduced to degree of protection 1P43. The certificate number of this equipment shall include the “X” suffix in accordance with the marking requirements of IEC 60079-0, and the Specific Conditions of Use listed on the certificate shall detail the restrictions of use.
When Ex components protected by powder filling q” are intended to be mounted inside another enclosure complying with IEC 60079-0, this outer enclosure shall have a degree of protection of at least lP54. The lP rating of the inner container does not need to be specified provided that the Ex component is mounted in a position where it is unlikely to be contaminated by any small amounts of water that may enter the outer enclosure.
NOTE 3 The impact and drop tests of enclosures from IEC 60079-0 do not generally apply to Ex Components intended to be mounted inside another enclosure complying with IEC 60079-0, as the external enclosure provides the protection against impact and drop.AS NZS 60079.5 pdf download.