Health and Safety Flashcards
(38 cards)
What are hydrocarbon combustion fuels?
Fuels like natural gas, propane, oil, and wood, that are composed of hydrogen and carbon. During combustion, oxygen combines with hydrocarbons, splitting the molecules and releasing heat.
What are the byproducts of combustion?
Carbon dioxide, water vapor, carbon monoxide (byproduct of incomplete combustion), oxygen, heat, and NO2, SO2, VOCs
What is spillage?
The release of combustion of by-products from combustion appliances during operation.
What is backdrafting?
Continuous spillage at a flue
What causes carbon monoxide release?
Incomplete combustion
Describe carbon monoxide.
Colorless, odorless, undetectable by senses - CO blocks oxygen to the brain and vital organs
What are the most effective solutions to handle dust?
Source control - don’t generate dust, cleaning, effective HVAC filters
What are some common VOC sources?
Combustion, solvents and cleaners, paints, furniture, drapery and carpet, gasoline
Where does radon come from?
Rocky soil
What is Asbestos?
A known carcinogen if inhaled. Comes from pipe insulation, floor tile, siding and roofing
What’s the number one enemy of buildings?
Water
What is capillary seepage?
Liquid water moving through tiny spaces. It redistributes water from liquid sources.
Water vapor moves in what two ways?
Through air movement and vapor diffusion. Diffusion movement depends on the permeance of the object and the vapor pressure difference.
What are some sources of liquid water in buildings?
Roof leaks, malfunctioning gutters, poor site drainage, undetected plumbing leaks
When do ice dams occur?
When snow melts and refreezes at a cold eave forcing water under the roofing and into building. They are a heat leakage problem, not roof.
Water vapor always flows from…
high pressure to low pressure (wet to dry)
_________ drives vapor diffusion through a difference in absolute humidity on two sides.
Vapor pressure
T/F: Water vapor is smaller and lighter than air.
True
What is relative humidity?
The percentage of the max moisture that air at a given temperature can hold. At 100% TH, air is saturated with moisture and condensation will occur with any additional moisture.
As air cools, its relative humidity _____.
increases
Condensation problems increase with:
Increase in absolute humidity
Decrease in temperature
A bathroom fan should have a CFM rating that provides ___ _______.
8 ACH (Air changes per hour)
Year-round natural ventilation should only occur in the following locations:
Attics and crawl spaces
Most codes require 1 square foot of vent for every ____ square feet of attic area.
150