Evacuation plan for explosion hazard zones – how does it differ from a standard plan and what should you pay attention to?

A standard evacuation plan is not sufficient when dealing with explosion hazard zones. Here, procedures must not only be faster, but also take into account the risk of ignition, the presence of explosive mixtures and limited response capabilities. This is not just a formal matter – the evacuation plan must be tailored to the specific characteristics of EX zones and based on hard data such as zone classification, type of combustible substances and potential ignition sources. Importantly, it cannot be a template. In this article, we show you exactly what such a plan must contain, how it differs from a typical evacuation plan, and how to ensure that it is up to date and effective.

Evacuation plan in explosion hazard zones – why is a “standard” evacuation plan not sufficient here?

The differences between the standard plan and the plan for explosion hazard zones are fundamental. Already at the level of passage lengths, equipment requirements and signage, you can see that it is not just a matter of “adapting” the existing document – but of a completely separate approach to hazards. In EX zones, response time and elimination of ignition sources are crucial.

What should you pay attention to at the design stage?

• The maximum length of an escape route is 40 m, regardless of the fire rating of the room.
  
• Emergency stop switches and alarm systems must be marked, certified and resistant to explosive atmospheres.
  
• The emergency lighting system must not emit sparks or exceed safe temperatures.
  
• Escape routes must be free of settled dust, uncertified equipment and flammable materials.
  

These are not just recommendations – they are strict requirements resulting from regulations, including the ATEX Directive 99/92/EC, the PN-EN 1127-1 standard and national regulations. Exceeding the limit for the length of an escape route or the presence of a standard LED lamp in zone 1 may result not only in a fine, but also in a real threat to life.

In many cases, evacuation plans fail because no one has checked beforehand what could cause ignition. The entry on minimum ignition energy will help you understand how important technical data is when designing protective measures and escape routes.

Building evacuation plan and ATEX zones – what does the classification of zones 0, 1, 2 and 20, 21, 22 actually change?

It is impossible to create an effective evacuation plan for a plant with explosive atmospheres without understanding what zones you are dealing with. Escape routes are planned differently for spaces where explosive atmospheres are constantly present (Zone 0) than for places where they occur only occasionally (Zone 2). Zone classification affects literally every element of the plan – from the type of equipment, through the number of drills, to the assembly point.

Below are the key differences.

• Zone 0 and 20 – explosive atmosphere present continuously or for long periods. Required equipment category: 1.
  
• Zone 1 and 21 – explosive atmosphere may occur during normal operation. Equipment: Category 2.
  
• Zone 2 and 22 – explosive atmosphere occurs rarely, for short periods. Equipment: category 3.
  

If you are planning an evacuation from zone 0 or 20, you must assume that there is no time for complicated procedures – every second counts here. In many cases, two independent escape routes, mandatory ATEX-certified emergency lighting and assembly points outside the boundaries of all zones are required. This means that even a seemingly “simple plan” requires a very specific approach and knowledge of technical standards.

Graphic evacuation plan and evacuation diagram – how to design them so that they actually reduce escape time?

In explosion hazard zones, there is no room for illegible diagrams and incomprehensible markings. A graphic evacuation plan must meet several very specific conditions in order to actually increase safety, rather than just “hanging on the wall”.

What must an evacuation plan for EX zones contain?

• Clear marking of zone classifications (e.g. 0, 1, 2, 20, 21, 22) along with their boundaries.
  
• Two independent escape routes with directional signage.
  
• Collection points located at least 100 m away from the zone – marked in accordance with ISO 7010.
  
• Locations of emergency switches, personal protective equipment and any fire extinguishing systems.
  
• Colour coding of risk levels – e.g. different backgrounds for zones 0 and 1.
  

It is also important that the plan is legible in emergency conditions, i.e. well lit and placed at eye level (1.6–2 m). What is more, it should be integrated with the Explosion Protection Document, rather than functioning as a separate Word document. If you plan to update it, remember that it must be reviewed at least once a year or after each change in the layout of the installation.

Fire evacuation plan in explosive atmospheres – alarms, emergency switches and procedures with no room for improvisation

In explosion hazard zones, time and flawless operation are crucial. That is why every second you can save by quickly cutting off the power supply or sounding an effective alarm can determine the scale of the threat – or its neutralisation. This is where the evacuation plan comes in, which must precisely indicate the locations of emergency switches, their markings and procedures for their use.

What specifically should be included in well-prepared documentation?

• Precise location of emergency switches for electrical, gas and technological installations, divided into zones.
  
• Markings compliant with PN and ISO standards – most often in the form of yellow and black warning stripes.
  
• Clear instructions for staff: when, how and who has the right to switch off a given system.
  
• Practical training in use – especially in establishments with high staff turnover or seasonal workers.
  

When it comes to alarms, they must not only be loud, but also resistant to explosive atmospheres. In many cases, parallel signalling systems are required: audible (modulated sirens, min. 3 minutes) and visual (e.g. flashing lights). These devices must be ATEX certified and have an emergency power supply, e.g. via a UPS system or batteries with the appropriate protection class. In an emergency situation, the signal must not be lost due to a power failure, which is why the plan must include redundancy scenarios.

Building evacuation plan in EX zones – emergency lighting, clear routes and elimination of ignition sources

Lighting in emergency conditions is not a matter of convenience, but of survival. In explosion-hazardous areas, standard luminaires can be a potential source of ignition – through sparks, excessive heating or micro-damage to the insulation. Therefore, all lighting devices on escape routes must be ATEX-compliant and designed for use in the relevant zone.

The most common requirements for emergency lighting:

• Minimum intensity of 1 lx on the axis of the escape route, 0.5 lx in open spaces.
  
• Operating time minimum 2 hours after power failure.
  
• Flameless and spark-free light source – most often LED with Ex enclosure.
  
• Resistance to dust, dirt and moisture (IP65 or higher).
  
• Uninterruptible power supply (UPS) systems located outside the danger zone.
  

The accessibility of escape routes is another issue that takes on a different dimension in EX zones. In addition to ensuring passage, you must eliminate the risk of secondary ignition. This means no flammable materials, no storage of non-certified equipment, systematic removal of settled dust, and a ban on installing devices not designed for use in explosive atmospheres. It seems obvious, but these points are most often overlooked during the initial audit.

Building evacuation plan and personal protective equipment – when antistatic clothing and escape masks are mandatory

Clothing and personal equipment are the first line of defence during evacuation from an explosion hazard zone. Unlike standard evacuation situations, the hazard here is not only fire, but also electrostatic sparks, combustible dust, oxygen deficiency, toxic gases and sudden pressure changes.

Therefore, every evacuation plan in a facility with explosive atmospheres must include providing employees with:

• antistatic clothing made of materials that prevent the accumulation of charges,
  
• electrostatic footwear, tailored to the zone classification,
  
• escape masks with filters or breathing apparatus – especially in zones 0 and 1,
  
• respiratory and eye protection equipment – for situations involving dust or chemical mists.
  

In practice, this means that it is not enough to have a few sets of PPE “in stock” – you must ensure that they are available and fit the actual number of people in the zone. What is more, the evacuation plan must precisely indicate the locations of equipment distribution points, rules for its use, and control procedures before entering the zone.

In many cases, verification of the validity of certificates and OOO inspections is also required, especially when breathing apparatus is involved. This cannot be done “as needed”. It must be planned in advance, described in procedures and checked regularly.

It is impossible to develop an effective evacuation plan without understanding what ignition sources may be present in your installation. These are the most common reasons for ineffective evacuation or escalation of the hazard.

Fire safety plan and assembly points – where does evacuation end in explosion hazard zones?

The escape route itself is not everything – where the escape ends is equally important. In ATEX zones, you cannot afford to have random assembly points “at the gate” or in the logistics area, where flammable substances may be present. According to health and safety standards and practices, the assembly point must be at least 100 metres from the boundary of the explosion hazard zone.

What else do you need to remember?

• Collection points should be located outside all EX zones – preferably in open areas.
  
• These locations must be clearly marked in accordance with ISO 7010 (pictogram E007).
  
• They must be accessible regardless of the escape route – in case it is blocked.
  
• They should be free of obstacles and hazardous materials, including stored barrels, pallet trucks, etc.
  
• It is worth considering shelters or canopies if people work at the facility all year round in variable weather conditions.
  

The evacuation plan must also indicate a specific person responsible for verifying the presence of employees at the assembly point. This cannot be a vague phrase such as “someone from the maintenance department” – the documentation must include their first name, surname and position. In addition, each evacuation drill should record the time, number of people, problems and the response of the evacuation manager.

Documentation, training and testing – how to keep your evacuation plan up to date and effective over time

An evacuation plan is not a once-and-for-all document. Conditions at the plant change, new installations appear, the composition of combustible mixtures changes, and sometimes… the crew changes. And that is why, in order to be effective, the plan must be regularly tested, updated and integrated with other elements of process safety.

Here is the minimum you should take care of:

• Update the plan at least once a year – or after any significant change in the installation, layout of rooms, number of employees, or occurrence of an incident.
  
• Storage in graphic and text form – accessible to employees and emergency services.
  
• Job-specific and general training – at least once a year, for zones 0 and 1: twice a year.
  
• Evacuation drills with full simulation – for zones 0 and 1: twice a year, for the rest: once a year.
  
• Tests of alarm signals and emergency lighting systems – at least twice a year.
  
• Documentation of every training session, exercise and update – as evidence in the event of an inspection or incident.
  

If you manage an industrial facility that is subject to the ATEX directive, an outdated evacuation plan is not only a risk of penalties, but above all a real threat to health and life. Even if everything works today, it does not mean that it will work tomorrow. And that is why the plan must be part of the safety management system, not an “appendix to the fire safety instructions”.

How does Atex Consulting help develop an effective evacuation plan in EX zones?

It is not enough to have a plan – you need to have a plan that works. At Atex Consulting, we help industrial plants and investors develop realistic evacuation plans for explosion hazard zones, tailored to the specific process conditions. We do not create templates – only documentation based on risk analysis, installation layout, zone classification and applicable standards.

As part of our cooperation, you can count on:

• comprehensive analysis of explosion hazards and risk assessment,
• updating or creating an evacuation plan as part of the DZPW,
• graphic designs of plans taking into account EX zones,
• development or verification of emergency procedures,
• training for employees and evacuation leaders,
• compliance audit and support during inspections.
  

If you want to be sure that your evacuation plan will not fail at a critical moment, contact us. We will take care of every detail: from emergency switches to the assembly point.

Frequently asked questions about evacuation in explosion hazard zones