NFPA 274-2018 Standard Test Method to Evaluate Fire Performance Characteristics of Pipe Insulation.
4.1 Size and Preparation. 4.1.1 The test specimen shall consist of the actual pipe insula‐ tion assemblies, including elbows, jackets, lagging, tapes, seal‐ ants, coatings, and adhesives, mounted on three DN 60 metric size or 2 in. nominal pipe size steel pipes. 4.1.2 The three steel pipes shall be L shaped, each with a verti‐ cal and horizontal section joined (by welding) with a short radius welded elbow of the same diameter. The horizontal section of the welded pipe, including the elbow, shall be 1120 mm ± 13 mm (44 in. ± 1 ∕ 2 in.) long, and the vertical section, including the elbow, shall be 1650 mm ± 13 mm (65 in. ± 1 ∕ 2 in.). Each pipe shall have a cap screwed to the end of the vertical run, the cap having a hole through which a threaded eyebolt has been fastened. The ends of the horizontal run of pipes shall not be capped. The eyebolt shall be opened to form a hook so that the pipe can be hung on the rod across the top of the chase. 4.1.3 The L-shaped steel pipes shall be covered with insulation assemblies. The vertical section of the insulation assembly shall be a minimum of 1520 mm (60 in.) from its top to the top of the horizontal section of the assembly.
5.1 Pipe Chase. 5.1.1 The chase shall be made of 1.37 mm [0.054 in. (16 gauge)] steel lined with nominal 13 mm (0.5 in.) thick calcium silicate board and stiffened with angle or bar stock. 5.1.2 The overall height inside the chase shall be 2030 mm ± 13 mm (80 in. ± 1 ∕ 2 in.), and the width shall be 610 mm ± 13 mm (24 in. ± 1 ∕ 2 in.), as shown in Figure 5.1.2. 5.1.3 The vertical section shall be 460 mm ± 13 mm (18 in. ± 1 ∕ 2 in.) deep, while the horizontal section shall be 460 mm ± 13 mm (18 in. ± 1 ∕ 2 in.) high and 1220 mm ± 13 mm (48 in. ± 1 ∕ 2 in.) deep, as shown in Figure 5.1.2. 5.1.4 Specimens mounted on steel pipes shall be hung from a 27 mm (1 1 ∕ 16 in.) diameter steel rod centered across the top of the vertical chase. 5.1.5 A pan to capture any dripping and falling materials shall be made to ft in the bottom of the chase. 5.1.6 The pan shall be made of tinned steel fashing material 710 mm (28 in.) wide and 1220 mm (48 in.) long. 5.1.7 Approximately 51 mm (2 in.) of either side of the 1220 mm (48 in.) length and one end shall be bent 90 degrees to form the sides of the pan that will ft into the bottom of the chase. 5.1.8 The open side of the pan shall face outward. 5.1.9 Heavy metal tape shall be used to cover any gaps between the pan and the walls of the chase. 5.1.10 The pan shall be replaced following any test after which material adheres to the pan.
NFPA 274 pdf download.