Safety Guide for Experiments at CERN
Part I - Orientation about safety at CERN

7. Alarms

Sensors of many kinds (smoke, water, temperature, electrical anomalies, etc.) provide the initial alarm signals. The sensors may be placed on, or related to, the individual particle detectors, or be available as part of the infrastructure. Alarms may be generated by an individual experiment set-up, a part of it, or by the experiment hall infrastructure. The sounding of alarms is not necessarily similar in the various areas and halls. It is therefore important that personnel in a given location should be familiar with the particular alarm sound.

Alarm Levels
Alarm-Handling
Non-Urgent Calls

7.1 - Alarm Levels

Alarm signals are classified into three levels of alarms:

Level 1 signifies equipment fault or fault of an installation. It requires the intervention of the competent technical service.
Level 2 signifies incorrect functioning of equipment or abnormal situation. It requires immediate intervention of the competent technical service.
Level 3 signifies accident or abnormal situation. The life of persons is or may be in danger. It requires immediate intervention of the Fire and Rescue Service.

7.1.1 - Level 1 and 2 Alarms

Level 1 and 2 alarms remain within the competence of the experiment or the technical service concerned. The possibility exists of letting the alarm signal alert directly the person responsible for a given equipment via the GSM alert system.).

7.1.2 - Level 3 Alarms

Level 3 alarms always alert the Fire and Rescue Service.
Events that generate level 3 alarms may originate from:
- Smoke (fire) detectors,
- Flammable gas detectors indicating serious leaks,
- Red telephones,
- General emergency stops,
- Oxygen level detectors,
- Water leak (flooding) detectors
- Local evacuation alarms,
- Blocked lifts with trapped occupants.

This list is not exhaustive, other alarms may be defined as level 3 alarms if necessary. The Safety Commission may require the installation of a level 3 alerm system where judged necessary.

Buildings, installations, underground areas and other premises must be fitted with a level 3 alarm system if there is a high risk for the staff or if the installation or equipment must be protected.

Level 3 alarms are transmitted via the computer networks to the alarm centre of the Fire and Rescue Service. All level 3 alarms must also be transmitted hardwired and fail-safe to this alarm centre. In many cases, the signals from a level 3 alarm system act in addition on technical equipment of other safety equipment.

The Safety Commission must be kept informed of the installation of any new level 3 alarm system as well as of alterations to existing ones.

The Fire and Rescue Service must be given detailed information on all level 3 alarm systems and, especially, the action to be taken following on alarm.

7.1.3 - Maintenance and Inspection

The departments or groups responsible for level 3 alarm systems must ensure that they are regularly maintained, inspected and calibrated according to the procedures laid down in collaboration with the Safety Commission.

A full test on all level 3 systems must be performed at least once a year in collaboration with the Safety Commission. The results of each test must be recorded in a report, one copy of which is intended for the Safety Commission.

Any interventions on the system must be recorded.

7.1.4 - Disabling of an Alarm System

If a level 3 alarm system has to be disabled, temporarily or definitely, a specific form has to be filled in and a procedure has to be followed as stated in Safety Instruction IS 37 Rev. 3 "Alarms and Alarm Systems". It is of the highest importance that this procedure be followed correctly, peoples' lives may otherwise be in danger.

7.2 - Alarm Handling

Alarms are transmitted to the Technical Control Room (TCR) and to the Safety Control Room (SCR) simultaneously by:

The CERN-wide alarm monitoring system automatically
Red telephone calls (manually)
General Emergency Power Cuts (manually)

A call to number 74444 is considered an alarm too but only for the fire and rescue service. Both TCR and SCR are always manned at all hours and every day of the year, by firemen of the Fire and Rescue Service and the staff of the Department TS.

Alarm call conversations are recorded and kept for one month and all alarms are automatically listed by a printer for future reference.

Having received an alarm via the alarm monitoring system or by a telephone call, the appropriate Fire and Rescue Services are then immediately dispatched to the alarm location. However, since all services are stationed on the Meyrin site, it can take up to 30 minutes or so for them to reach the furthest underground LEP sites.

While waiting, apply what you have learned in fire fighting and first aid courses. Don't forget to post somebody at the entrance to the area or building to guide the Rescue Team when it arrives.

7.3 - Non-Urgent Calls

Any non-urgent call to the Fire and Rescue Service should be made to number 74848.

DSO

Modified on July 27, 2004