RE: DATACENTER: FM-200

[Sean Donelan <sean@donelan.com>]

On Fri, 11 February 2000, "Julian, Dennis R." wrote:
> The need for FM-200 type protection should be based on the actual and
> perceived risk seen by the client and any perceived benefit of minimizing
> damage and downtime.

I would carefully examine assumptions that a total flooding system such as
FM200 will minimize damage and downtime as actually implemented.  Under some
conditions they do, under other conditions they aggrievate the situation. I'm
not sure total flooding is always the best solution for huge, multi-tenant,
continuous availability facilities.  Since these mega-datacenters are
relatively recent developments, we don't have a lot of experience yet.

I suggest keeping the compartments as small as possible.  Less than 5,000
sq/ft in most cases, and never larger than 25,000 sq/ft.  But I've found
six months after opening, most co-location compartments are swiss-cheese,
reducing the effectiveness of total flooding systems.  

Even though it discusses fire suppression in the context of telephone
central offices, for a relatively brief look at the the trade-offs I
recommend getting a copy of Bellcore's/Telcordia's special report:

AUTOMATIC FIRE SUPPRESSION SYSTEMS IN TELEPHONE EQUIPMENT BUILDINGS

Document Number SR-3882
Issue Number 01
Issue Date May 1996
Product Type Industry Requirements And Standards (RS)
ORDERING INFORMATION

ABSTRACT: Manual fire suppression using gaseous suppression agents,
especially Halon 1211, has historically been very effective in extinguishing
fires in Central Office (CO) buildings. Various alternatives to manual Halon
1211 have been considered, including automatic sprinklers, water-mist systems,
and other gaseous-agent systems. This Special Report (SR) provides information
regarding the effectiveness and limitations of using automatic fire-suppression
systems in telephone equipment buildings. It is intended to provide
telecommunications risk-managers and fire protection staff, building design
professionals, building-code officials, and other interested individuals with a
detailed understanding of the expected performance of such systems.

See http://www.telcordia.com/ for ordering information.