ATEX based and organizational measures for explosion protection
ATEX Inspection
If safety in a working environment cannot be guaranteed by technical measures only, organizationalprecautions must be taken. In practice, a safe working environment is created by a combination of technical and organizational precautions.
Organizational precautions to protect against hazards
Prevent explosion hazard at your work processes
Work processes must be organized in such a way that workers cannot be harmed by an explosion. The inspection, maintenance and repair of technical measures must also be recorded by the organization.
When taking organizational measures, it is important to consider how precautionary measures and work processes may interact. Thecombination of the two must ensure workers can carry out their work without endangering the health and safety of themselves and others.
Organizational precautions to protect against the risk of explosion must be realized as follows:
- Drawing up operating instructions;
- Instructing employees on explosion safety;
- Adequate qualification of employees;
- Applying a work permit system for hazardous work;
- Carrying out maintenance work;
- Carrying out investigations and checks;
- Marking hazardous areas.
The organizational precautions must be recorded in the explosion protection document.
Operating instructions for explosion safety
Operating instructions are written regulations and rules of conduct concerning the work carried out. They describe the hazards at a specific location and point out the precautionary measures.
The instructions for areas where explosive atmospheres may occur must clearly indicate the risks involved, which mobile work equipment may be used and whether personal protective equipment must be used.
The operating instructions must be such that every employee can understand and apply them. If there are workers within the company who do not have a sufficient command of the local language, the operating instructions must be written in a language they understand.
Operating instructions describing different hazards and those drawn up on based ondifferent legal requirements may be combined into a single operating instruction. To make them easily recognizable, a uniform design of operating instructions is recommended.
Sufficiently qualified workers
At every worksite sufficient employees with the required knowledge and experience of explosion protection must be available.
ATEX Training of workers
Through training employees must be informed of the following aspects of their worksite:
- The explosion hazards present;
- The source of the explosion hazard;
- The areas where the explosion hazard is present;
- The safety precautions taken;
- The effect of safety precautions;
- Which mobile work equipment may be used where;
- The meaning of markings used in explosion-hazardous areas.
In addition, the correct use of the available work equipment must be explained and training must be provided on how to carry out the work safely. The use of mandatory personal protective equipment must be pointed out. Training should also cover any operating instructions applicable.
ATEX Training of the employee must take place at:
- Initial appointment (before starting to work);
- A transfer or a change of function;
- Introduction or modification of work equipment;
- Introduction of a new technology.
Employees should be trained repeatedly at appropriate intervals. This can be done, for example, once a year.
The training obligation also applies to employees from other firms. The training must be done by a competent person. The date, content of the training and the list of participants must be recorded.
Supervision of workers to prevent explosion hazards
In areas where explosive atmospheres may occur which may endanger health and safety, adequate supervision must be provided when workers are present. Monitoring must be in accordance with the risk assessment and must be supported by adequate technical means.
Work permits ATEX guidelines
If work is to be carried out in a hazardous area or its immediate vicinity that could lead to an explosion, permission must be given by the person responsible from the company. This is arranged by means of work permits. A work permit prevents unsafe situations and ensures good communication between the parties involved in the work.
Before the work instructions and permits are drawn up, an assessment is made to determine whether hazardous actions can be prevented. If this is not the case, a permit is granted.
Work permits apply to activities such as:
- Working in confined spaces e.g. in tanks, sewers and silos;
- Lifting operations;
- Diving work;
- Excavation work for underground cables and pipes;
- Grinding and welding work.
Two parties are involved in issuing a work permit, the applicant and the authorized person.
The applicant is the person responsible for the work to be carried out (e.g., the foreman of an external company). He fills out his application indicating which precautions should be taken and which personal protective equipment is needed.
The authorized person is the one who issues the work permit. For example, the company manager or production manager. The authorized person:
- Completes the permit and signs it himself;
- Ensures that the company and all subcontractors are named and sign the permit;
- He issues the permit shortly before work begins and only if all of the conditions are met;
- If necessary, he transfers the permit to his successor and has his successor sign the permit;
- At the end of the work, or if the work is terminated prematurely, the permit is returned to the person responsible;
- The work permit is archived by the company or department at the end of the work.
A work permit is issued under the following conditions:
- The work permit is in the name of the person(s) performing the work and is not transferable;
- The work permit is only valid for the specified day and time;
- If conditions change significantly, the work must be stopped and the work permit must be handed in. A new work permit may be requested;
- The work permit must be present at the workplace;
- All operations stated in the work permit must indeed be carried out.
A work permit records or prescribes the following:
- Pressure relief of drums, pipes and the like;
- Cleaning the installation;
- Gas measurements prior to and possibly during work;
- Personal protective equipment;
- Extinguishing devices;
- Special precautions;
- Applicable work instructions;
- Measures taken to execute the work correctly;
- Appointment of a supervisor to oversee the work.
A work permit may be withdrawn if one of the parties involved creates a dangerous situation which is not eliminated after an explicit request by the other. A qualified person from either the requesting or issuing party will revoke the work permit.This is always accompanied by a suspension of work.
After completion of the work, it must be checked whether the safety of the installation is (still) intact. All those involved must be informed of the completion of the work.
Performing maintenance
Maintenance includes repair, upkeep, inspection and testing of equipment and installations. Before starting work, all parties involved must be informed and a permit must be granted to carry out the work. Maintenance may only be carried out by authorized personnel.
During maintenance there is a high risk of accidents. Therefore, before, during and after completion of the work, care must be taken to ensure all necessary precautions are in place. If possible, potential ignition sources should be isolated.
For example, if work involving fire is to be carried out in a container, all connecting pipelines possibly containing hazardous explosive atmospheres must be sealed off. This can be done by, for example, fitting blind flanges.
When work in an explosion hazard area entails ignition hazard, the presence of any explosive atmosphere must be excluded. This must be ensured for the duration of maintenance and, if necessary, longer.
As necessary, parts of the installation will be:
- Emptied;
- Depressurized;
- Cleaned;
- Rinsed;
- Freed of flammable substances.
Appropriate protective measures must be taken when working with flying sparks, e.g., when welding, burning, grinding. If necessary, a fire watch should be set up.
Protection against sparks
After completion of the work and before commissioning, it must be ensured that all required explosion protection measures are reactivated.
ATEX Inspection and control
Before initial commissioning of a site where a hazardous explosive atmosphere may be present, the safety of the installation must be checked. The safety of the entire installation must also be rechecked after changes to the installation and after incidents involving damage.
The explosion protection measures taken must be examined at regular intervals to determine their effectiveness. The frequency of the check must be adapted to the nature of the measure.
Inspections may only be carried out by qualified personnel. These are people who have extensive professional knowledge of explosion safety through their training, experience and current professional practice.
Marking of explosion hazardous areas
Where needed, the employer must mark places where hazardous explosive atmospheres may be present in accordance with Directive 1999/92/EC. This is done by placing the following warning sign at the entrances.
Ex zone sign
The sign is characterized by:
- a triangular shape;
- black letters on a yellow background with a black border (the safety color yellow must cover at least 50% of the surface of the sign).
Such marking is required for spaces or areas where hazardous explosive atmospheres may occur (e.g., flammable liquid storage areas). If only part of the space is a hazardous area, this may be indicated by a yellow-black shading on the floor.
An additional sign below may indicate the nature and frequency of the presence of hazardous explosive atmospheres. The sign is often combined with others such as no smoking, no cell phone use, etc.
As part of their training, workers must be instructed on the markings and their exactmeaning.
