Firestopping is a term used to describe sealing and protecting openings and other joints between the cable and edges of the floor, wall, or ceiling. Firestopping was first practiced on U.S. combat ships in the 1960s. The walls and floors of the ships had steel tubes, which allowed conduits to pass through. Then, non-burning material was stuffed between the gaps, preventing the spread of fire and smoke. It wasn’t until the 1970s when larger companies began producing firestopping materials.
A successful firestop plan requires careful planning. Here are three tips to help you meet the needs of future cabling requirements and fire protection:
#1. Think long term
Most people tend to underestimate the size of the openings required for cabling and often forget about future expansion. When planning on how large to make the opening to run your cable, you must consider the diameter of the cable itself, how much room you need for firestopping materials, and whether you’ll be adding more cables in the future.
#2. Different cabling systems require different firestops
There are two basic types of cabling systems: permanent and retrofittable. Permanent cabling systems, such as electrical cables, do not change. But most cabling systems, such as data and voice, have to accommodate moves, adds, and changes so they need to be retrofittable. You use different firestops with each system.
In permanent installations, a sealant is used in and around the cables. This is also appropriate for external areas, including conduits and sleeves.
In retrofittable systems, firestops need to be removed and reinstalled easily as cable needs change. Common firestops include pillows, putty, and fire-rated pathways. These products are packed in and around a cable bundle rather than being injected the way sealant is. The product to use often depends on the size of the cable opening and the frequency of changes.
#3. Use the proper materials
There are two basic types of materials used in firestopping: Passive firestopping uses nonintumescent materials, which draw heat away or insulate the cables. Passive materials include mortars, silicone sealants, foam, and grout. Cabling runs with passive firestopping are generally thicker and are more limited in the types of cables they can protect.
Intumescent materials expand when exposed to heat or fire and compensate for the loss of mass in cable bundles. They’re a good choice for sealing and surrounding cable holes and runs.