Risk Assessment; Heat Hazards; Pressure Hazards; Possible Intoxication - Stropuva S7 Installation And Maintenance Manual

Upon touch of hot boiler elements, it is possible to get burnt. The surface of the boiler which can
be heated up to 40º C temperature and other parts according to technical characteristics are insulated
with heat insulation but there are such parts like door handles and doors which are heated more and are
hazardous to humans. Such places are marked with an international danger mark. Hot water pipes of
the heating system after hydraulic testing must be insulated with heat insulation. Pressure valve escape
pipe must be lead up to sewerage or vessel by leaving a 10 cm gap for monitoring and insulated with
heat insulation or marked with a heat hazard mark.
Increase of pressure is possible: when electric power fails and circular pump stops, the boiler is
not refilled with cold water from a system and temperature reaches the dangerous level then the
draught regulator gets actuated by closing a valve at the set temperature mode, not letting air in and
extinguishing the boiler. Temperature can reach the critical level of 100° C from inertia but water will
not boil in the boiler since thanks to a combustion method a small layer of burning firewood logs upon
an automatic closure of the air valve quickly goes down. If the air closing valve is deformed or due to
other violations of operation rules (for instance, the door from ash cleaning is open) water in the boiler
can start boiling. However the pressure protection valve mounted on the upper pipe of the feeding flow
near the boiler easily releases vapor and does not exceed pressure, allows the boiler to get replenished
with water from a reversionary water flow pipe from a system and to cool down.
Under improper use: for instance though the air is injected through a lower door into the boiler
due to the intensive combustion in the boiler its capacity is exceeded several times so the boiler can
boil water and if overheated crack up from normal pressure.
The boiler can also crack up from too high pressure, if a pressure protection valve of higher
pressure will be mounted in an improper place or clogged. As calculations and practice prove the boiler
will never explode to the outside but crack up inside therefore there is no hazard for human health or
life.
When the chimney flue is clogged or when cleaning from ash, carbon black monoxide can be
formed in a boiler room therefore natural exhaust ventilation is required and for its operation the
influent ventilation is required too, i.e. the opening or opened small window in the outside wall of a
boiler room. If there is no influent ventilation the boiler shall not operate. Therefore do not forget to
install the inflowing ventilation in the boiler wall of a boiler room directly from outside. The door of a
boiler room must be tightly closed so that when an emergency sanitary unit or kitchen ventilation are
switched on the operation of the boiler shall not be disturbed and dust or carbon black monoxide shall
not pass from a boiler room into residential rooms.

10. RISK ASSESSMENT

10.1. HEAT HAZARDS

10.2. PRESSURE HAZARDS

10.3. POSSIBLE INTOXICATION

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