Chapter 4: Smoke control acceptance and testing 
60  VM-1 Smoke Management Application Guide 
pressure difference across the door, measure the force 
necessary to open each door, using a spring-type scale. 
The building system designer should establish a 
consistent procedure for recording data throughout the 
entire test . The stair tower side of the doors will always 
be considered as the reference point and the floor side 
of the doors will always have the pressure difference 
value (positive if higher than the stair tower and negative 
when less than the stair tower). Since the stair tower 
pressurization system is intended to produce a positive 
pressure within the stair tower, all negative pressure 
values recorded on the floor side of the doors indicate a 
potential airflow into the floor. 
The VM-1 system designer, working with the building 
system designer, should verify the proper activation of 
the stair tower pressurization systems in response to all 
means of activation, both automatic and manual, as 
specified in the contract documents. Where automatic 
activation is required in response to alarm signals 
received from the building’s smoke control system, each 
separate alarm signal should be initiated to ensure that 
proper automatic activation occurs. Automatic weekly 
testing of dedicated systems should be conducted to 
verify all components operate as installed and 
programmed and that the test time is agreeable to the 
building owners. Verify and document the proper 
operation of all fans, dampers, indicators, and related 
equipment for each separate smoke control system 
zone. 
With the stair tower pressurization system activated, the 
building system designer should measure and record the 
pressure difference at points similar to those evaluated 
in zoned smoke control and atrium systems.  
After recording the pressure difference across each 
closed door, measure the force necessary to open each 
door. Use the established procedure to record data 
throughout the test. The local code and contract 
documents should be followed regarding the door to be 
opened for this test. 
With the stair tower pressurization system activated, 
open the doors required by the system design, one at a 
time, and measure and record the pressure difference 
across each remaining closed stair tower doors after the 
opening of each additional door. After recording the 
pressure difference across each closed door, measure 
the force necessary to open each door. Use the 
established procedure to record data throughout the test. 
The local code and contract document requirements 
should be followed regarding the number and location of 
doors that need to be opened for this test. 
With the stair tower system activated, and all required 
doors open, determine and record the direction of airflow 
through each of the open doors. This can be done by 
using a small amount of smoke at the open doorway. If 
velocity measurements are required, a door opening 
traverse needs to be performed with the door fully open. 
Stairwell pressurization systems typically have a smoke 
detector at the stair intake to stop fans should smoke 
begin to enter from the outside. There must be a manual 
override on the system to keep fans operating should a 
qualified emergency person determine that the smoke 
infiltration is minor. Testing of the override feature should 
be in the acceptance procedure. 
Elevator shaft pressurization 
systems 
Shaft systems may incorporate exhausting of air from 
the fire floor, pressurization of elevator lobbies, 
pressurization of the elevator hoistway or by construction 
of smoke tight elevator lobbies with pressurization. The 
type or combination of designs will dictate system 
operation and testing. Elevator recall and the use of 
elevators while the shaft or lobby is pressurized will be 
an integral part of the test procedure developed. 
The piston effect due to car movement on elevator shaft 
pressurization has been researched and is discussed in 
several of the texts referenced in Chapter 1. There are 
no recommended tests to determine how shaft 
pressurization might be impacted with car movement. 
Elevator door testing currently assumes a median value 
for pressures developed against a door independent of 
car movement. No dynamic testing of the shaft 
pressurization system with car movement is therefore 
dictated. 
The building system designer must define smoke control 
sequences for design and testing and measure and 
record pressure differences in a manner similar to those 
described for stairwells. 
Using smoke control input devices, verify the proper 
activation of the shaft pressurization system in response 
to all means of activation, both automatic and manual, 
as specified in the contract documents. Where automatic 
activation is required in response to alarm signals 
received from the building smoke control system, each