Q: I've made my home more energy-efficient and I'm concerned about carbon monoxide (CO) gas poisoning. I've heard that CO gas-poisoning symptoms often are mistaken for the flu. How can I check my home?
A: Carbon monoxide is an odorless, colorless, tasteless gas that kills thousands of people each year, many in their sleep. It is estimated that many thousands more suffer short- and long-term health problems from low-concentration CO gas poisoning without ever realizing the cause.
Many of the initial CO gas poisoning symptoms are very similar to flu symptoms -- persistent headaches, sleepiness, lack of energy, nausea, weakness, reddening of face, red or burning eyes, shortness of breath, etc. Consult your physician if you have these symptoms.
In any house, especially an energy-efficient, airtight one, it is a good idea to continually monitor the CO gas level in the air. The level of CO gas in your home can vary from hour to hour and day to day.
With incomplete combustion, any fuel-burning appliance in your home -- gas or oil furnace, water heater, fireplace, gas range -- can produce CO gas in high-enough levels to cause death. People die each year from using the oven in their gas ranges to supplement their furnaces on cold nights.
There are several types of do-it-yourself CO gas-monitoring alarms you can use in your home. The simplest to use are 9-volt-battery-operated continuous sensors. These resemble ceiling-mounted smoke alarms and make a similar loud alert tone when dangerous levels of CO gas are detected.
The battery and the inexpensive sensor cartridge usually need to be replaced once a year.
You can also install 110-volt house current CO gas monitors. Some also warn you of smoke and natural gas in the air.
The latest development in monitoring devices uses a "dose monitor" sensor. This sensor mimics the poisoning effect CO gas has on your body. It actually absorbs and expels CO gas at the same rate as your blood and sounds the alarm when an unsafe CO gas level persists.
You can also use inexpensive CO gas-sensitive tablets. Some use dose-monitor sensor material. These tablets change color when CO gas is present. You should mount these at several locations in your home -- near furnace and water heater, fireplace and bedroom. The refrigerator door is a good spot because it is seen many times each day.
You can write to me for "Utility Bills Update No. 230," listing addresses and telephone numbers of manufacturers of CO gas alarms and testing tablets and product information, and tips on reducing the risk of CO poisoning in your home. Please include $1.50 and a self-addressed business-size envelope.
Q: I have dark ceramic tile in my foyer for solar heat collection from the south-facing windows. The grout is cracking because the subfloor flexes. How can I stiffen it?
A: Dark ceramic tile is an excellent surface for solar heating, but it can get too heavy for an ordinary floor. You can stiffen the floor by nailing 1-by-4 or 1-by-6 lumber to the lower edge of the floor joists. This creates an I-beam member cross section. Using construction adhesive before you nail them to the joists also increases stiffness.
Write to James Dulley, c/o Baltimore Sun, 6906 Royalgreen Drive, Cincinnati, Ohio 45244.