Safety and Measurement in Construction

Ladder Safety

• The ladder base should be positioned one-fourth of the ladder length away from the structure against which the ladder is leaning.

Scaffolding

• The maximum height of horses supporting scaffold platforms is 16 ft (4.88 m).

Fire Extinguishers

• A dry powder CO2 extinguisher is composed of 99% baking soda and 1% drying agent.

Measuring Instruments

• A hygrometer is used to measure relative humidity.

Heat Transfer

• Heat can be transferred through three methods: conduction, convection, and radiation.

Vacuum

• A vacuum is a space entirely devoid of matter.
• A partial vacuum is a space where an air pressure exists that is less than atmospheric.

Band Iron and Thinwall Tubing

• 32 teeth per inch (13 teeth per cm) is best for light gauge band iron and thinwall tubing.

Drawing and Measurements

• A sectional elevation drawing provides information on the width and height of a specific portion of a structure.
• Elevation measurements on piping plans are called invert elevations.

Leveling

• Two main parts are required for shooting grade levels: the dumpy level and the leveling rod.
• The dumpy level rotates in a horizontal plane only.
• The leveling rod is also known as a dumpy level and is marked off in 10ths and 100ths.

Heating Systems

• Water heated from 32°F to 212°F (0°C to 100°C) expands approximately 1/23 of its original volume.
• Absolute pressure is the sum of gauge pressure and atmospheric pressure.

Storage Tanks

• Storage tanks with a capacity up to 82 gallons (310.4 liters) are tapped for 1" (25 mm) connections.
• Tanks with a capacity over 82 gallons are tapped a minimum of 1 1/4" (32 mm) generally.

Asbestos Cement Water Main Pressure Pipe

• The standard length of asbestos cement water main pressure pipe is 13 ft (approximately 4 m).

Plumbing Systems

• The installation of a water softener in a residential piping system causes a fairly high pressure loss.
• Pipe size measurements are always given in N.P.S.-I.D. or inside diameter.
• The building drain is the lowest horizontal piping inside the building and connects with the building sewer.
• The building sewer extends from the main sewer or other disposal terminal to the building drain at a distance of approximately 5' (152 cm) from the foundation wall.

Sewer Systems

• Public sewer manholes can be used to verify main sewer elevations and direction of flow.
• Gases found in sewer air include carbon monoxide, methane, hydrogen sulphide, carbon dioxide, gasoline, ammonia, and sulphur dioxide.
• Primary treatment in a sewage treatment plant removes floating and settleable solids.
• Secondary treatment removes dissolved solids.
• No garbage disposal unit shall be installed on any indirect fresh-air waste system or into any grease interceptor.

Ladder Safety

• The ladder base should be positioned one-fourth of the ladder length away from the structure against which the ladder is leaning.

Scaffolding

• The maximum height of horses supporting scaffold platforms is 16 ft (4.88 m).

Fire Extinguishers

• A dry powder CO2 extinguisher is composed of 99% baking soda and 1% drying agent.

Measuring Instruments

• A hygrometer is used to measure relative humidity.

Heat Transfer

• Heat can be transferred through three methods: conduction, convection, and radiation.

Vacuum

• A vacuum is a space entirely devoid of matter.
• A partial vacuum is a space where an air pressure exists that is less than atmospheric.

Band Iron and Thinwall Tubing

• 32 teeth per inch (13 teeth per cm) is best for light gauge band iron and thinwall tubing.

Drawing and Measurements

• A sectional elevation drawing provides information on the width and height of a specific portion of a structure.
• Elevation measurements on piping plans are called invert elevations.

Leveling

• Two main parts are required for shooting grade levels: the dumpy level and the leveling rod.
• The dumpy level rotates in a horizontal plane only.
• The leveling rod is also known as a dumpy level and is marked off in 10ths and 100ths.

Heating Systems

• Water heated from 32°F to 212°F (0°C to 100°C) expands approximately 1/23 of its original volume.
• Absolute pressure is the sum of gauge pressure and atmospheric pressure.

Storage Tanks

• Storage tanks with a capacity up to 82 gallons (310.4 liters) are tapped for 1" (25 mm) connections.
• Tanks with a capacity over 82 gallons are tapped a minimum of 1 1/4" (32 mm) generally.

Asbestos Cement Water Main Pressure Pipe

• The standard length of asbestos cement water main pressure pipe is 13 ft (approximately 4 m).

Plumbing Systems

• The installation of a water softener in a residential piping system causes a fairly high pressure loss.
• Pipe size measurements are always given in N.P.S.-I.D. or inside diameter.
• The building drain is the lowest horizontal piping inside the building and connects with the building sewer.
• The building sewer extends from the main sewer or other disposal terminal to the building drain at a distance of approximately 5' (152 cm) from the foundation wall.

Sewer Systems

• Public sewer manholes can be used to verify main sewer elevations and direction of flow.
• Gases found in sewer air include carbon monoxide, methane, hydrogen sulphide, carbon dioxide, gasoline, ammonia, and sulphur dioxide.
• Primary treatment in a sewage treatment plant removes floating and settleable solids.
• Secondary treatment removes dissolved solids.
• No garbage disposal unit shall be installed on any indirect fresh-air waste system or into any grease interceptor.