English to Russian Tech/Engineering Manufacturing

PROJECT SPECIFICATION
AMMONIA PLANT UTILITIES
OPERATING MANUAL

STARTUP BOILER AND BFW SYSTEM
PACKAGE BOILER
To shut down the boiler in an emergency, perform the following:
• Depress the Stop pushbutton.
• Close the main fuel gas cock.
• Leave forced draft fan running for 30 minutes, if possible and safe to do so.
• Open steam drum vent halfway.
• Close non-return valve when boiler is cool enough that the safety valves will not lift.
If a leak develops in a boiler, superheater or economizer tube, reduce boiler outputand if water level can be maintained in the *steam drum level indicator* follow thenormal shutdown procedure.

Не могу до конца понять фразу "if water level can be maintained in the *steam drum level indicator*" - если можно поддерживать уровень воды в индикаторе уровня паросборника? или пропущено "by" и должно быть "if water level can be maintained in the *steam drum BY level indicator*?

Спасибо.