Exd 32-tone sound signaling device PGZ-REVUN32 (EMHS-12, EMH-12MD, EMHS-20, EMH-20MD)

According to GOST R IEC 60073-2000, sound signals may be applied in cases when:

– it is required to draw an operator‘s attention;

– coded information will be short, simple and transient;

– the information requires immediate time-dependent answer;

– application of visual signal is limited;

– the situation is critical and it requires additional or redundant information.

The sound signal may consist of pure or complex tones (not more than 5 signals). The sound signal must be audible and easily recognized by operators and people in the set area of signal reception and at set background noise conditions. Signals must be different from the emergency signal, as per ISO 8201 part 7.

Sound signals of different types must be clearly distinguishable from each other.

Limited audibility of signals must be also taken into account in cases, when employees wear protective devices or earphones, as well as people with hearing impairment.

Selection of emergency sound signaling device

General rules of identification of sound signals when coding the information:

1. Continuous, sharply intensifying sound means danger (danger to the safety of people or equipment), critical (process status), malfunction (equipment status).

2. Intermittent sound with constant interval means attention (safety of people or equipment), transient (process status), transient (equipment status).

3. Continuous sound with permanent level means safety (safety of people or equipment), normal (process status), normal (equipment status).

4. Interchanging sounds have special meaning, as per technological documentation.

5. Other sounds do not have special meaning and cannot be easily identified by operators, not desirable.

To prevent sound overpressure of operators, it is required to use minimum amount of sounds of different kind in this application.

Intermittent sound signal may be used in some particular cases (for example, in case of change of dangerous or transient state to a safe state). 

Sound signals should not be applied in case of safe state (silence).