Safety System - Thermo Scientific Safe 2020 Operating Instructions Manual

4. Unit description
4.2

Safety system

The safety system comprises a combination of protective and alarm systems
that ensure maximum personal and material protection.
Safety systems:
• Vacuum-sealed air system
A vacuum-sealed air system in combination with HEPA filters for downflow
and exhaust air forms the basis of the safety system for personal and
material protection.
• Personal protection
Air aspired from the exterior along the entire working opening at a constant
high velocity prevents that:
• agents may leak through the working opening of the chamber.
As the exterior air pressure around the unit exceeds the pressure of the
internal air system (vacuum sealing), it is ensured that:
• agents cannot be released to the exterior in the case of a leak in the
cabinet housing.
• Material protection
A steady airflow within the air system ensures that:
• a constant downflow allows the HEPA filters to remove contaminants
so that the samples are always surrounded by ultrapure air,
• harmful particles are not carried over through the sample chamber
(protection from cross-contamination).
• HEPA filters
The downflow (i.e. the air circulating within the device) and the exhaust air
(air that is released to the exterior) are cleaned by HEPA filters (HEPA = High
Efficiency Particulate Air Filter).
For version Maxisafe 2020, a prefiltering system is used to increase the fil-
ter efficiency and to protect the exhaust air and downflow systems.
• Safety lockout
To protect from UV radiation, the optional UV disinfection routine can be run
only if the front opening is closed. During UV disinfection, the front opening
safety lockout is activated and prevents harmful UV radiation from being
emitted from the sample chamber.
Warning system:
• Airflow monitoring
Airflow monitoring determines the velocity of the airflow in the sample chamber
as well as the inflow velocity of the air aspired from the exterior through the
working opening. As soon as airflow velocities move above or below a
specified safety value, a signal is transmitted to the alarm system.
• Visual and audible alarm system
The warning system constantly monitors the safety-relevant device functions:
• Inflow velocity of the air aspired from the exterior,
• downflow velocity,
• working position of the front window.
If the warning system detects changes to one of these device functions, it
issues:
• an audible and a visual alarm signal.
Operating Instructions Safety Cabinet Safe 2020 / Maxisafe 2020
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