Mass timber construction is a relatively new type of construction soon to be implemented in the National Building Code of Canada (NBCC). It is a cost-competitive wood-based solution that complements existing wood-frame and heavy timber systems and is a suitable candidate for some applications which currently use concrete, masonry and/or steel.
Reduced surface evaporation rates are marketed as a competitive advantage by water-enhancer manufacturers. In this report, a new test method is developed and applied to quantify the evaporation rates of various commercially available water-enhancer products in a controlled environment. These quantified evaporation rates were then compared to the evaporation rate of water which served as the benchmark.
Alberta Agriculture and Forestry’s (AAF) Wildfire Management Branch has recently contracted two Sikorsky S-61N heavy helicopters. Both helicopters are equipped with an external tank (max. volume 1000 U.S. gallons) and have on-board injection systems that are capable of mixing class A foams and water-enhancers.
Currently, there is limited data on comparative drop footprints of foam and water-enhancers (suppressants) for these heavy helicopters. To fill this knowledge gap, AAF has asked FPInnovations to conduct drop tests in different wildland fuel environments. This study focuses on mapping the drop footprints of water, foam, and water-enhancers in an open field at specific flight parameters.
In 2020, Alberta Agriculture and Forestry’s (AAF) Wildfire Management Branch contracted two externally tanked heavy helicopters with on-board injection and mixing systems. The two heavy helicopters are Sikorsky S-61N helicopters with modified Isolair tanks, capable of dropping water, foam, and water-enhancers. Drop tests were conducted using these helicopters to understand the relative footprints of different suppressants.
This study focuses on using drop footprint data to estimate recovery rates of water, foam, and water-enhancers in two scenarios – an open field and a forested stand. These estimates may provide a primarily understanding of how best different suppressants can be used for different applications.
Alberta Agriculture and Forestry’s (AAF) Wildfire Management Branch recently contracted two Sikorsky S-61N heavy helicopters. Both helicopters are equipped with an external tank (max. volume 1000 U.S. gallons) and have on-board injection systems that are capable of mixing class A foams and water-enhancers.
Currently, there is limited data on comparative drop footprints of foam and water-enhancers (suppressants) for these heavy helicopters. To fill this knowledge gap, AAF has asked FPInnovations to conduct drop tests in different wildland fuel environments. This study focuses on mapping the drop footprints of water, foam, and water-enhancers in black spruce stands at specific flight parameters.
Modified oxygen consumption calorimetry was used to track the seasonal flammability of black spruce and tamarack. Age class related samples were collected for both species from May to September at research site in central Alberta. These samples were assessed for their differential heat release using test equipment at the Protective Clothing and Equipment Research Facility (PCERF) at the University of Alberta.
The test method was able to successfully quantify the differences in seasonal flammability between black spruce and tamarack. Data showed the age-related flammability differences were less pronounced, with the exception of new growth samples early in the season.
The objective of this research is to address a knowledge gap related to fire performance of midply shear walls. Testing has already been done to establish the structural performance of these assemblies. To ensure their safe implementation and their broad acceptance, this project will establish fire resistance ratings for midply shear walls. Fire tests will provide information for the development of design considerations for midply shear walls and confirm that they can achieve at least 1-hour fire-resistance ratings that are required for use in mid-rise buildings.
This research will support greater adoption of mid-rise residential and non-residential wood-frame construction and improve competition with similar buildings of noncombustible construction. This work will also support the development of the APA system report for midply walls, which will be a design guideline for using midply walls in North America.
WoodST is capable of calculating heat transfer, charring rate, load-displacement curve as well as the time and mode of failure of timber structures exposed to fire, thus providing a cost-competitive solution for the fire safety analysis of timber structures. This InfoNote briefly introduces the development and verification of WoodST. Two applications of WoodST are also demonstrated.
FPInnovations’ Wildfire Operations Advisory group has asked its researchers to explore a method by which the performance of water-enhancing products can be repeatedly assessed in the laboratory. A new test method, known as the crib test, was designed to evaluate the effectiveness of water-enhancing products on burning woody fuel to simulate direct-attack aerial operations.
This report outlines the methodology for the crib test and describes the findings from performance evaluation tests conducted at the Protective Clothing and Equipment Research Facility (PCERF) at the University of Alberta.
The USDA Forest Service’s Qualified Product List (QPL) provides guidance on the range of permissible mix ratios for water-enhancer products. Due to the proprietary nature of water-enhancer products, there are several unknowns about the rheology of the permissible mix ratios.
This study focused on mapping the viscosity of various suppressant products as a function of their mix ratios. The results revealed a wide range of viscosities across products, with each product showing a different non-linear relationship with different mix ratios.
The results from this study can help understand the optimum viscosity range to achieve desired drop characteristics during aerial operations.