Local Alerting System (LSO): What It Is, Who Must Have One, and What Equipment It Uses

A local alerting system (LSO, from the Russian «локальная система оповещения») is the facility-level tier of the unified emergency alerting network. In plain terms, we break down what it actually is, which sites are required to have one, and the equipment it is built from in practice.

How does an LSO differ from a regional alerting system (RASTSO)?

RASTSO is Russia's regional automated centralized alerting system, managed centrally at the regional level. An LSO is a local system installed at a specific site: it delivers the signal to everyone within the facility's coverage area and, where required, ties into RASTSO through an interface unit. Put simply, RASTSO covers the region while the LSO covers the individual site.

Does every site need an LSO?

No. The obligation depends on the type and characteristics of the site — as a rule these are hazardous production facilities, hydraulic structures, mass-occupancy buildings, and critical life-support infrastructure. The exact legal basis and the site's category are established by a licensed engineering firm as part of the design; VPA supplies equipment against a finished specification.

What is the minimum equipment set for an LSO?

The core chain is a signal source, a PA amplifier with a priority input, 70/100V lines, and loudspeakers for indoor and outdoor areas. If the site connects to the regional alerting network, an interface unit for RASTSO (P-166Ts BUU-02) is added.

Is the P-166Ts BUU-02 interface unit always required?

No — only when the site must receive signals from the regional alerting system (RASTSO). Without that requirement, the LSO runs standalone from a PA amplifier with a priority input. Whether the interface is needed is determined by the requirements for the site and by the design decision.

Can a single amplifier cover both indoor and outdoor areas?

Yes, provided the amplifier has enough power and load headroom and the lines run at 70/100V. Indoor and outdoor areas connect to a shared 70/100V line, but all-weather loudspeakers are chosen for the outdoor zones. The exact power rating and equipment set are quick to estimate with our online calculator.

Does VPA supply a complete turnkey system?

VPA supplies equipment ex-stock from Moscow with delivery throughout Russia and helps match the configuration to your task. Design, site categorization, and installation are carried out by a licensed firm. Orders are placed by invoice for business customers — through the “Request an invoice” button.