Intumescent Free

POSITIVE PRESSURE DOOR INFORMATION

METHODS OF COMPLIANCE
Positive pressure openings can be accomplished in two basic ways:

The first is described as Category “A” doors.
DOORS-NO ADDITIONAL EDGE-SEALING SYSTEM REQUIRED
This category includes doors evaluated without any intumescent on either the frame or door. It also includes doors evaluated with intumescent incorporated into the edge of the door by manufacture or licensed machiner.

The second method is called Category “B” doors.
DOORS-ADDITIONAL EDGE-SEALING SYSTEM REQUIRED
This category includes doors evaluated with an intumescent applied to the frame-either surface applied or built in.

S LABEL SMOKE RATING
Many positive pressure openings will also require a smoke seal. An “S” label requirement indicates the opening needs to have Smoke and Draft Control Gasketing. This category “H” includes gasket systems that are surface-applied (such as kerf applied, adhesive backed or mechanically attached) to frames or doors. It includes gasketing for the meeting edges for use in pair and double egress assemblies. This category covers gasket systems that have been evaluated for use in positive pressure rated assemblies but not provide an edge-sealing system to the opening as described below.

EDGE-SEALING SYSTEMS
This category “G” includes intumescent-type systems that are surface applied (such as kerf applied, adhesive backed or mechanically attached) to frames or doors. It includes seals for meeting edges for use in pair and double egress assemblies.

DOOR SPECIFICATION DESCRIPTIONS
Section G-1, of the WDMA I.S. 1-A lists the different types of flush door construction available in the industry. Fire rated doors for positive pressure openings are designed with “PP” suffix. Stile and Rail door co construction as described by WDMA I.S.6A are also available for positive pressure openings based on specific manufacturer’s approvals.