prEN 1127-1 rev

Explosive atmospheres - Explosion prevention and protection - Part 1: Basic concepts and methodology

Scope

This document specifies methods for the identification and assessment of hazardous situations leading to explosion and the design and construction measures appropriate for the required safety. This is achieved by:
— risk assessment;

— risk reduction.

The safety of equipment, protective systems and components can be achieved by eliminating hazards and/or limiting the risk, i.e. by steps (figure below from ISO EN 12100):
a) appropriate design (without using safeguarding) – Step 1;

b) safeguarding – Step 2;

c) information for use – Step 3;

d) any other preventive measures.

In this standard the measures in accordance with

a) (prevention) and
b) (protection) against explosions are dealt with in Clause 6.

The measures according to
c) against explosions are dealt with in Clause 7.

Measures in accordance with d) are not specified in this standard.

Refer to EN ISO 12100:2010 for complementary preventive and protective measures

Inherently safe design measures are the first and most important step in the risk reduction process. This is because protective measures inherent to the characteristics of the product or system are likely to remain effective, whereas experience has shown that even well-designed guards and protective devices can fail or be violated, and information for use might not be followed.
Guards and protective devices shall be used whenever an inherently safe design measure does not reasonably make it possible either to remove hazards or to sufficiently reduce risks. Complementary protective measures involving additional equipment (e.g. emergency stop equipment) might have to be implemented.
The end user has a role to play in the risk reduction procedure by complying with the information provided by the designer/supplier. However, information for use shall not be a substitute for the correct application of inherently safe design measures, guards or complementary protective measures.

The preventive and protective measures described in this document will not provide the required level of safety unless the equipment, protective systems and components are operated within their intended use and are installed and maintained according to the relevant codes of practice or requirements.
This document specifies general design and construction methods to help designers and manufacturers in achieving explosion safety in the design of equipment, protective systems and components.
This document is applicable to any equipment, protective systems and components intended to be used in potentially explosive atmospheres, under atmospheric conditions. These atmospheres can arise from flammable/combustible substances processed, used or released by the equipment, protective systems and components or from materials in the vicinity of the equipment, protective systems and components and/or from the materials of construction of the equipment, protective systems and components.

This document is applicable to equipment, protective systems and components at all stages of its use.
This document is only applicable to equipment group II which is intended for use in other places than underground parts of mines and those parts of surface installations of such mines endangered by firedamp and/or combustible dust.

Related legislation

Legislation related to this standard