What is BS EN 13463-2 - Construction and testing of flow restricting enclosures for nonelectrical equipment about?
BS EN 13463-2 specifies the requirements for the construction and testing of flow restricting enclosures for nonelectrical equipment intended for use in potentially explosive atmospheres if the atmosphere outside the enclosure becomes explosive rarely and for short durations only.
BS EN 13463-2 supplements the requirements in EN 13463-1 the contents of which apply in full to equipment constructed in accordance with BS EN 13463-2.
Equipment complying with t BS EN 13463-2 meets the requirements of Group II – Category 3 equipment. The type of ignition protection described in this standard is unsuitable for use in combination with another type of protection to produce equipment of any other category than category 3.
Who is BS EN 13463-2 - Construction and testing of flow restricting enclosures for nonelectrical equipment for?
BS EN 13463-2 on construction and testing of flow restricting enclosures for nonelectrical equipment is useful for:
- Manufacturers of flow restricting enclosures
- Equipment manufacturers
- Safety/ hazard protection bodies
Why should you use BS EN 13463-2 - Construction and testing of flow restricting enclosures for nonelectrical equipment?
An explosive atmosphere surrounding an enclosure can penetrate it mainly due to the influence of three
mechanisms:
- Ventilation
- Equalisation of pressure differences between the inside and outside (breathing)
- Diffusion
If such an enclosure is effectively sealed, but not necessarily gas-tight, it can be assumed that ventilation and diffusion will not cause a significant short-time exchange of atmosphere. Under these conditions, an exchange of the external and internal atmospheres through the seals will only take place if there is a pressure difference across them. Such pressure differences may be caused by changes in temperature and will result in the enclosure "breathing" but will not cause a significant flow of explosive atmosphere into or through the enclosure.
Experience has shown that even simple enclosures can prevent a surrounding explosive atmosphere from reaching ignition sources inside them. Flow restricting enclosures are such simple enclosures, which will prevent, with adequate probability, the atmosphere inside the enclosures from becoming explosive if the atmosphere outside the enclosure becomes explosive rarely and for short durations only. For this reason, their use is restricted to the fulfillment of category 3 requirements.
BS EN 13463-2 provides guidance on protection by flow restricting enclosures that may be applied in different circumstances, instructions for use, marking, essential safety requirements, verifications, and tests for flow-restricting enclosures.
