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 CHAPTER 7
ESCALATORS
7.1 INTRODUCTION
NOTE: Paragraphs identified with a vertical line in the left margin are inspections that should
be made by Inspectors only.
7.1.1 Scope
The inspection of escalators included in this chapter is not only an inspection of all safety
related functions, but is also an inspection to determine the condition of the equipment and
identify areas that need improvement. Proper maintenance is needed to keep the escalator
operating. When preventive maintenance is lacking, shut downs will occur. Part III of
the ANSI/ASME A17.2 Inspector's Manual for Elevators and Escalators addresses the safety
aspect of the inspection of escalators. In this chapter we will identify the specific Division of
Part III which relates directly to the inspection procedure being followed in this text. It is
intended that each noted division should be reviewed as it is identified and suggested
procedures followed. The maintenance and performance considerations of the inspection will be
addressed in the following text. See Figures 7-1, 7-2, and 7-3 which show various escalator
arrangements with component names that will be used in this chapter.
7.1.2 Performance Criteria
As was stated previously, the purpose of this type of inspection is to review the entire
escalator installation; this includes measuring the operation of specific elements of the system
against standards which have been established either by national codes or engineering practice
common to the escalator industry. The components of the system selected for testing are those
most directly related to safe operation of the escalator and the overall installation, although some
items, such as speed of the escalator, are related to the efficiency of the operation and grade of
service provided. The following is an explanation of the areas that should be tested and
criteria to use for evaluating this performance.
7.1.2.1 Escalator Operating Speed. Escalator operating speed is measured with a tachometer
held against the deck while riding on the unit. operating speed should be maintained at a level of
plus or minus 5% of the speed under any load condition in both directions of travel. A second
speed test should be performed by holding a tachometer on the handrail while standing at the
top or bottom landing. Both handrails and the step speeds should be very close. A speed
variation might indicate a condition of handrail slip.
7-1
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