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Flashcards in Safety & Materials Period 1 (CND) Deck (280)
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1

Ductile Iron Has what in it?

Usually Magnesium

2

Cast iron is found in one of two form?

Graphite flakes or Chemically dissolved

3

Minimum weight of DWV cast iron soil pipe in Alberta?

18kn or 4000lbs

4

Another name for Cleanouts?

Barrett

5

Caulking lead must be how pure?

97.3%

6

Cutting a short piece of cast iron with snap cutters you should?

Place a smaller diameter piece of cast iron inside the larger piece to prevent the cutoff shooting out.

7

Amount of lead required in a joint?

3/4 pound per inch diameter

8

Torque required to tighten MJ screws?

55 to 60 inch pounds

9

Cutting of glass pipe is done with a ?

Glass cutter

10

3 hazards of working with fibre glass pipe?

Dust, fumes & chemicals

11

Alberta building code: The minimum size of flashing is?

20"x20" or 500mmx500mm

12

Chemical symbol for lead?

Pb

13

The word plumber comes from where? and what does it mean?

Comes from the Latin word PLUMBUM and means worker of lead.

14

A pound of lead per square foot results in a sheet of lead being?

1/65 thick

15

Flashing are typically _____pounds of lead & are _____ of an inch thick.

5lbs & 5/64

16

Vitrified clay pipe will carry every known chemical except?

Hydrofluoric acid

17

4 trade names for non-metallic pipe made of asbestos?

Trasite, Roxite, eternite, & Century

18

when bevelling or cutting asbestos cement pipe you need?

Protection from inhalation of the fibres

19

Disadvantage of using cement joints in a trench?

It is difficult for the cement to set up if there is water in the trench.

20

4 reasons for supporting pipe?

*to carry the weight, *grade the pipe, *prevent sagging or deflection of the pipe, * allow for thermal movement & settlement of the building,

21

3 points that should be considered when deciding on the spacing for hangers on a steel pipe?

*the material from which the pipe is made, *type & location of the joints, *& size of the piping.

22

Another word for Deviation from the centre line or snaking?

Deflection

23

Slope on the pipe to ensure the movement of the contents in the piping system

Grade

24

Max Hanger Spacing: 1/2" or less Horizontal?

2m or 6ft

25

Max Hanger Spacing: 3/4" to 1" Horizontal?

2.5m to 8ft

26

Max Hanger Spacing: 1-1/4" to 2-1/2" Horizontal?

3m or 10ft

27

Max Hanger Spacing: 3" to 4" Horizontal?

5m or 15ft

28

Max Hanger Spacing: 5" to 8" Horizontal?

6m or 20ft

29

Max Hanger Spacing: 10" or larger Horizontal?

8m or 25ft

30

Max Hanger Spacing: 1-1\4" or lager vertical?

Every floor but more than 125% of horizontal spacing

31

Tubing, Copper, Aluminum, Stainless steel, Horizontal or vertical. all sizes?

2m or 6ft

32

Fasteners that are to be placed in a wall, ceiling or floor you should give consideration to what?

Unseen hazards in the base of the material

33

Sheet metal screws have a greater?

Mechanical advantage than wood screws

34

2 categories that fasteners anchors are divided into?

Heavy duty & light duty

35

Lubricant trapped under a bolt or stud being tightened is called?

Hydraulic lock

36

The holding power of anchors is greatly influenced by?

the cleanliness of the hole

37

Adhesive anchors are considered to be ?

Heavy duty anchors

38

A metal or metallic alloy that is melted and then used to join metallic surfaces together?

Solder

39

What sizes are copper TUBING available in?

1/8" to 3/4"

40

What is the difference between Soft & Silver solder?

Soft uses temps below 575 C
and
Silver uses temps above 575 C

41

What are the types & colours for copper?

Type K - Green
Type L - Blue
Type M - Red
Type H - White
Type DWV - Yellow

42

To heat then cool which softens & makes the copper more flexible?

Annealing

43

What are 3 joint types & joining methods of copper?

Solder, Compressing & Flaring

44

The most common & oldest method of joining pipe?

Soldering

45

Streamline fittings are also referred to as?

Solder Fittings

46

The main application for type M copper is?

Light commercial buildings & residential

47

What is the coefficient of expansion of copper?

.0000171 per degree centigrade

48

Oxygen lines are run with medical type ____ copper pipe.

Types K & L

49

3 Applications for DWV copper?

Soil, Waste & drainage

50

What are the different solder types?

50/50, 95/5, lead free, Aquqsol, bridgit, & silvabrite 100

51

What does the 50/50 solder mean?

50% lead & 50% tin

52

What sizes lengths are DWV tube in?

1-1/4" to 6" and 12' to 20'

53

Copper is made from ____% and has ____% impurities in it.

99.7% and .3%

54

Yellow Brass ____% copper ____% zinc

66% and 34%

55

Red brass ___% copper ___% zinc

85% and 15%

56

Bronze ___% copper ____% tin

90% and 10%

57

S.P.S means?

Standard Pipe Sizes

58

Copper TUBE is measured by its approx.?

ID

59

Copper TUBING is measured by it actual?

OD

60

Copper tube used on drainage & venting can be joined by 2 methods?

Soldering & MJ's

61

Copper tube can be used for above ground water lines and can be joined by 4 methods?

Brazing, Soldering, Flaring, & Compression

62

What angle of flare is utilized in the pipe trade?

45 degree

63

2 purposes of fluxing?

To prevent oxidation & to promote wetting of the metal

64

Water lines connected to some plumbing fixtures utilize a flex tube connector. What type of seal is used?

Compression ferrule

65

Water lines connected to some plumbing fixtures utilize a flex tube connector. What is the minimum diameter allowed?

1/4" ID

66

Water lines connected to some plumbing fixtures utilize a flex tube connector. Plumbing code also stipulates a max length which is?

750mm or 30" (Clause 2.6.3.4.3)

67

Alloy pipe is a ferrous pipe that contains?

Iron ore, copper, Chromium

68

wall thickness changes as the ____ changes on the iron pipe.

ID

69

The ____ remains the same to enable pipe to be threaded.

OD

70

5 Pipe end finishes are?

*Grooved,
*Threaded,
*threaded & Coupled
*Plain,
*Bevelled

71

what aids in the formation & cleaning away the swarf during the threading process?

Lubrication & Cooling

72

Mineral-lard oils are used for?

Threading or machining copper alloys

73

resistance to flow through a fully open butterfly valve is?

Minimal

74

Non-Ferrous pipe may contain?

Copper

75

Grade of carbon content to manufacture steel pipe is?

.1% and .2%

76

The top of a thread is known as the ?

Crest

77

Joint compound should be applied on the ?

Male end of the pipe

78

True or False: Type M copper is the least wall thickness used in flaring?

False

79

Most used valve in the plumbing industry? and why?

Ball Valve, Because of its laminar flow easy operation & easy to repair.

80

To prevent backflow or reverse flow within the piping system?

Check Valves

81

2 types of check valves? and 3rd for Bonus.

Swing Check, Lift Check & Non slam Check

82

What type of valve is most suited to throttling?

Globe Valve

83

Why would you choose a globe valve for your system?

For adjustment and/or throttling flow

84

To Start and stop flow nd can be used in any application?

Ball Valve

85

Sulphured oils have a tendency to stain certain non-ferrous metals such as copper. What oil is used more often?

Mineral lard oils

86

What materials (7) is soluble oil used for?

Cast iron, malleable iron, free machining steel, monel, brass, copper and aluminium

87

Never use a spiral reamer with a ?

Power vise

88

3 advantages to copper tube over steel pipe?

Malleability, ductility, good resistance to corrosion

89

3 applications of type K copper tube?

Water service lines, water distribution lines, low pressure steam lines, heating system, gas fitting & DWV systems

90

What is the disadvantage of copper over iron or steel?

Its high rate of coefficient expansion

91

uses thread cutting oil or thread cutting compounds?

Steel & wrought iron

92

Uses a special high sulphur content cutting oil?

stainless steel

93

Uses mineral lard oil?

Copper pipe

94

Uses soapy water?

Brass pipe

95

Use a lubricant for oil less cutters

Plastic Pipe

96

Which valves can accommodate flow in either direction?

Gate, Ball, Plug, Butterfly

97

4 types of disc design for globe valves?

Needle valve, Plug disc, conventional disc, & composition disc

98

Threads do not come in contact with fluid?

OS&Y valve (Outside, Screw & Yoke)

99

1 type of quarter turn valve?

Plug or Ball valve

100

A horizontal lift, vertical lift & swing are types of?

Check valves

101

most common application of a plug valve?

Gas fitting

102

Specific reference to a gate valve, the _____ wedge disc design is most commonly used.

Split

103

Compared to a straight pattern globe valve, flow through the angle pattern globe valve is?

Less turbulent

104

K & L soft temper type tubing is most commonly used for?

Residential underground water systems

105

True or False: Is brass a ferrous metal?

False

106

True or False: Cast iron pipe is not approved for residential service?

False

107

Max. working temp. of ABS pipe?

180*F or 83*C

108

Max. working temp. and pressure of CPVC pipe?

212*F or 100*C and 58psi or 400kpa

109

True or False: Can you use system 15 pipe cement with out primer?

True you can use system 15 without primer

110

What colour is fire suppression CPVC piping?

orange

111

The only plastic pipe schedule that can be threaded is?

Schedule 80

112

Define Nesting?

Smaller diameter pipes stored inside larger diameter pipes.

113

Dunnage should not be spaced more than?

3ft or 1m

114

Dizziness or a feeling of euphoria is usually the first signs of ?

lack of oxygen

115

Solvent cementing is to be done in temps between?

5*C (40*F) & 44*C (112*F)

116

2 classes of plastic pipe?

Thermoplastic & thermosetting

117

Co-efficient of expansion of ABS & PVC plastic pipe?

ABS - .000099*C or .000055*F
PVC- .0000594*C or .000033*F

118

UV sunlight will do what to plastic pipe?

cause deterioration of the pipe.

119

Advantages of plastic pipe over ferrous pipe?

Low absorption rate,
Light in weight,
easily prefabricated,
easy methods of joining,
economical,
absorbs vibration & shock well,
Smoother bore,
less friction loss,
high corrosion resistance,
unaffected by electronic corrosion,
resistant to a wide range of chemicals

120

Disadvantages of plastic pipe?

High co-efficient of expansion,
low tensile strength,
Creep,
deformation under load,
low heat resistance,
low ductility,
low fire resistance

121

Name 3 plastic type materials that are best suited for acid waste & vents?

Polyethylene, Polypropylene, Proxylene

122

Type of plastic very similar to polypropylene & its colour?

Proxylene and Blue

123

Polypropylene pipes & fittings are what colour?

Brown

124

Plumbing code states rigid plastic pipe must be supported every _____ & flex plastic pipe should be supported _____.

1.2m (4ft), .8m (30")

125

Plastic acid waste pipes maybe joined by?

Fusion welds & Acid resistant MJ's

126

Standard length of DWV plastic pipe?

12ft

127

2 types of plastic tube best suited for radiant panel heating?

Pex & PE/AL/PE

128

3 types of plastic pipe for domestic water?

PEX, PE/AL/PE & Polyethylene

129

2 types of plastic pipe for hot water heating systems?

PEX, & PE/AL/PE

130

Required to be absolutely clean & free of rust, grease, paint & other matter?

Pickled & oiled pipe

131

Pitch decreases as the bolt size increases. A 3/8" bolt has ____ threads

16 threads

132

Pitch decreases as the bolt size increases. A 1/2" bolt has _____threads.

13 threads

133

Pitch decreases as the bolt size increases. A 5/8" bolt has ____ threads.

11 threads

134

Standard threads have a slight taper so when they are tightened into a good fitting a_____?

Good leak proof seal results

135

Which pipe needs cleaner/primer before applying solvent cement?

PVC Pipe

136

2 types of plastic pipe that produce toxic gases?

PVC & CPVC

137

3 types of plastic that can be joined with solvent cement?

ABS, PVC, CPVC

138

Prior to assembly of a compression joint it is critical that the tube be cut?

Square & cleaned of any burrs internally & externally

139

To move very slowly in the hangers as with expansion or contraction of the plastic pipe due to temp. change?

Creep

140

If we have a proper thread we should be able to hand tighten the joint?

3-4 turns

141

65 R self centring hand threader will cut on pipe sizes?

1" to 2"

142

ABS/PVC DWV horizontal piping must be installed with pipe supports every?

1m or 3ft

143

In a 2"x2"x1" tee the one refers to the ?

Branch

144

True or False: Copper tube K, L, & M are only available in coil for soft copper?

False

145

The schedule number for double extra strong pipe is?

160

146

True or False: Silicon is the element added to duriron that is responsible for its unique properties?

True

147

True or False: A socket weld fitting has 2 weld locations 1 inside & 1 outside?

False

148

The basic types of valves used in the pipe trade that can't be throttled?

Plug & gate valves,
Check & Ball valves

149

Riser clamps are available in what sizes?

1/2" to 20"

150

When installing a dummy leg to support a piping system you must ensure?

the dummy leg is equipped with a vent & weep hole to allow condensate to drain & allow built up gases to escape

151

which type of flange is welded to the pipe in two places?

lap-joint flange

152

True or False: the laying length of a cast iron hub & spigot pipe is measured from where the bottom of the bell to the end of the pipe?

True

153

True or False: Gate valves come with solid & split wedges?

True

154

Which of the following materials could pipe for the pipe trades be manufactured from?

Wood, Plastic, Steel, & Lead

155

True or False: Cross linked polyethylene pipe comes in 20' straight lengths & 100' coils?

True

156

True or False: Acrylonitrile Butadiene Styrene comes in bell & spigot lengths?

False

157

True or False: The type of steel pipe used for domestic water lines in commercial use would be galvanized ?

True

158

Yellow solvent cement is used with which type of cement?

ABS

159

A 4" cast iron 1/6 bend would be considered to be a ?

22-1/2 degree elbow

160

The melting temp. of tin is?

450*F

161

the measurement from the face of a standard black fitting to centre of the fitting is called?

the throw

162

The thread angle on a tapered thread is?

60 degrees

163

The abbreviation "NPT" stands for?

National Pipe Thread

164

Type M Copper pipe____ be bent.

Can not

165

Asbestos cement pipe installed above ground vertically must be supported every?

7.5m or 25ft

166

The amount of lead required for a hot poured vertical cast iron joint is?

3/4" of a pound for every 1" diameter.
or
1-1/2" of a pound for every 2" in diameter

167

True or False: DWV copper pipe should not be bent?

true

168

4 of the most common ways to weld steel pipe are?

ERW, Spiral wed, Butt-weld, Seamless weld

169

True or False: Type H copper pipe has the thinnest wall?

true

170

Why do most tape measures have a loose end that slightly moves?

To compensate for the inside & outside measurements

171

Why should the acetylene torch valve always be set to work above the smoke range?

It reduces the possibility of back fire & burn backs.

172

Class C fire is classified as?

electrical

173

Most pliers exert pressure on the grasping end through a version of a _______.

First class lever

174

The recommended shank penetration when fastening into concrete?

6 to 8 times the shank diameter.

175

Where are fusible plugs used?

on top & bottom of acetylene tanks

176

The side rail of every ladder shall extend what minimum distance above any platform?

3ft or 1m

177

Type of knot or bend used for tying two ropes of different diameters?

Sheet bend

178

when must you wear safety glasses?

when there is a danger of injury or irritation to your eyes

179

True or False: prior to installing a new disc on a grinder you should always perform a ring check of the disc & install only discs that have a lower RPM rating?

False

180

True or False: Whenever possible, wrench handles should be pushed not pulled?

False

181

How many studs are required for bolting up a 12" flange?

20 bolts

182

What is the purpose of the packing nut in a valve?

To prevent fluid leakage

183

What recommended bevel angle should be ground onto the flat end of a pipe to be welded?

37-1/2 degrees

184

What is used to check the temp of the plastic for fusion welding?

temp Sticks

185

The plastic pipe used for underground gas line is?

HDPE

186

What does the schedule number of a pipe designate?

the pressure/stress ratio x1000

187

Socket weld fittings are commonly used to join?

2" or smaller diameter piping

188

An marker used to mark steel pipe for cutting?

Wraparound

189

A weld neck flange is welded in how many locations?

1 location

190

What approximate bevel angle must be placed on a pipe prior to welding?

37.5 degree

191

What is the best tool for removing burrs or slag from the inside diameter of pipe that is cut?

Half round bastard fie

192

What face must be ground on the bevel prior to butt welding?

Root face

193

Large bore piping that requires regular disassembly should be joined by?

Flanged connections

194

The most common cast iron flanges are also known as?

Companion flanges

195

A flange that is beveled and has a land (root face) is known as a ?

Weld neck flange

196

Which types of flanges always come in a matched set?

Orifice

197

Raised face flanges have face heights of?

1/16

198

What gasket is always used with a flat face flange?

Full Face

199

A slip on flange is welded in how many locations?

2 locations

200

A van stone flange is known by what other name?

Lap joint

201

Gasket material should be stored in a?

Cool dry location

202

For easy future removal or opening of flanged joints, apply?

Graphite or non-stick compound to one or both surfaces of the gasket

203

Which tool should be used to separate two flanges?

Flange spreader

204

When installing gaskets, pay careful attention to the type of fluid in the line and match the gasket to the?

Pressure and temperature of the line.

205

Class A fire is classified as?

Ordinary Combustibles

206

Class B fire is classified as?

Flammable liquids and gases

207

Class C fire is classified as?

Electrical

208

When is it necessary to install guardrails around the perimeter of the roof?

for a worker to fall a vertical distance greater than 3.5 metres from a
temporary work area or 1.2 metres from a permanent work area

209

Class D fire classified as?

Combustible metals

210

Class K fire classified as?

Combustible oil or grease

211

If you are an apprentice and are entitled to Workers' compensation because of an accident, how much compensation will you receive? Workers' Compensation Act Section 62(2)

an amount that may be adjusted during the time you have become qualified in your trade

212

Who is responsible for the actual usage of the personal protective equipment supplied?

You the employee

213

Hex keys are available in _____ and _____ sizes.

Metric and Imperial

214

A hacksaw blade with _____ teeth per inch is recommended to cut type M copper tube.

32

215

True or False: An "excavation" is defined as: Any dug out area of ground other than a trench, tunnel, underground shaft or an open pit mine.

true

216

What are two advantages of cast iron over copper tube for use in a drainage, waste or vent system?

Better corrosion resistance, Lower expansion rate

217

True or False: It is recommended that all valves be installed in the horizontal position.

False

218

What is meant by the term alloy as applied to the manufacture of ferrous pipe?

Other metals mixed with iron to produce special qualities in pipe

219

True or False: Copper pipe is measured by its approximate ID up to 6” and by its actual OD for 8” and over.

False

220

What are the three basic flange face types of gaskets?

Full face, Flat ring and Metallic

221

The two materials that are not safe to fasten to when using an explosive actuated tool are?

Tempered steel, Spring steel

222

When checking the diameter of a rope, the size must always be taken:

across the widest point

223

True or False: The teeth of a hacksaw blade face backward, so the cutting is done with the pull stroke?

False

224

What is the minimum recommended thickness of concrete that you can safely fasten to?

75mm or 3 inches

225

Oil or grease in contact with pure oxygen can?

React violently and cause an explosion.

226

The wide rollers found on a pipe cutter help prevent the _____.

Cutter wheel from spiralling along the pipe

227

Before entering a vessel to make repairs, a plumber should insist on testing the vessel for:

fumes and oxygen deficiency.

228

Mushroomed areas of chisels must be _____.

Ground away to prevent flying splinters that pose a potential hazard

229

Safe working load is the:

breaking strength divided by the safety factor.

230

Yes or No:Can a competent worker designated by the employer remove a lockout device or tag as long
as he/she has first ensured that no workers will be endangered by the removal?

Yes

231

When working around welding operations you must wear eye protection due to three types of harmful rays that you may encounter. What are the three types of harmful rays?

Visible, Infrared , Ultraviolet

232

What is the proper formula used to calculate the centre to face measurement for a 90º, long radius butt weld elbow?

NPS x 1½

233

Most pliers exert pressure on the grasping end through a version of a _____.

First class lever

234

What is the recommended shank penetration for good holding power when fastening into concrete?

Six to eight times the shank diameter`

235

The side rails of every ladder shall extend what minimum distance above any platform or landing?

3 feet/ 1 meter

236

The hook or tang of a tape measure is loose in order to accommodate _____.

Inside measurements by allowing for the hook or tang thickness

237

The type of knot or bend used for tying two ropes of different diameters together is the:

sheet bend.

238

When must you wear safety glasses?

When there is a danger of injury or irritation to your eyes.

239

True or False:Prior to installing a new disc on a grinder you should always perform a ring check of the disc and install only discs that have an rpm rating lower than the RPM rating of the tool?

False

240

When tightening a fitting onto a pipe, the fitting should be turned by hand approximately 4 to 6½ times and made up with the aid of a wrench approximately _____ to _____ turns.

 
2 to 3 turns

241

What is the purpose of the Packing nut in a valve?

To hold the packing which prevents fluid leakage

242

What does the schedule number of a pipe designate?

The schedule number of a pipe designates the pressure/stress ratio X 1000.

243

What wrench would you use to tighten a spud nut on a water closet with? and what size does the wrench only come in?

Spud wrench and 12"

244

A version of a first class lever?

Pliers

245

A version of a third class ever?

Pry bar

246

Edge - the narrow section called a safe edge when no teeth are cut into it. Is on what tool?

File

247

NPT? and ASPT?

National Pipe Thread and American Standard Pipe Thread

248

Uses a blade with 32 teeth per inch on thin-walled tubing and conduit and on sheet metal thinner that 18 gauge?

Hacksaw

249

3 cardinal rules of tool maintenance?

Clean, Oil & replace

250

How many strokes per minute should you stroke a hacksaw?

40 to 50 strokes

251

The employer shall ensure that cylinders containing acetylene are?

Secured in a vertical position

252

If you are to use CO2 for freezing, what is the first thing to check for?

That you have enough CO2 on hand to complete the job.

253

Files cut when _____ ______ only.

Pushed Forward

254

What must take place in solids and liquids before burning can occur (before the fuel can ignite into flames)?

Vaporization of the surface must take place.

255

True or False: A trench is defined as an elongated dug out area of ground whose depth is equal to its width at the bottom?

False

256

Why are the cylinder valves cracked before the regulators are attached?

To remove dust or dirt from the cylinder valve.

257

True or False: The two purpose of the lead in a caulked cast iron joint are to seal the joint and prevent the oakum from peeling out over time?

False

258

Before butt welding plastic pipe and fittings, you must ensure that the_____.

The pipe ends are square.

259

How much does a thread taper amount to if extended to 1 FT in length?

The taper amount is 3/4" increase in diameter at 12".

260

The loss of pressure in the line caused by the valve or fitting in relationship to a length of pipe is defined as?

Equivalent length.

261

Four characteristic properties of gray cast iron are?

Hard, Brittle, Good wear resistance, Good corrosion resistance

262

When must your employer ensure that you are wearing safety footwear?

Where danger of injury to your feet exists.

263

What is the primary safety feature of an industrial plant site?

Automatic sprinkler system.

264

When are you ineligible for compensation as the result of an accident?

If the injury is attributable primary to your serious and wilful misconduct.

265

Above what height must an employer have a guardrail erected for a temporary work area?

3 meters

266

At what height must guardrails be installed on scaffold platforms?

Not less than .92m nor more than 1.07m

267

If platforms are a specified height, a toe-board must be installed when there may be workers below. What is the platform height that requires toe-boards to be installed?

For materials to fall more than 2m or 4m from a temporary platform.

268

What is the minimum distance from the edge of the trench that the material removed from an excavation (spoil pile) must be kept?

3.28ft or 1 meter

269

True or False: It is a workers responsibility to ensure that he/she is wearing appropriate eye protection when there is a danger of injury to the eye?

False

270

True or False: The load to which a scaffold is subjected should at no time exceed the equivalent of 1/2 of the load for which it is designed?

False

271

True or False: When installing shoring in a trench, a worker shall use a ladder and work upward from the bottom of the trench?

False

272

True or False: A worker shall not work 1m from the top of a portable single or extension ladder?

False

273

Housekeeping which provides safe working conditions shall be ensured by the?

Employer

274

Workers and equipment shall not operate within ____ meters of live overhead power lines.

7 meters

275

Operators of explosive activated fastening tools must be _____ and _____ in the use of each model of tool the operator may be called on to use.

Instructed and Trained

276

True or False: A worker shall grind on the side of an abrasive wheel but shall not a adjust a tool rest while the grinder is in motion?

False

277

Sharp edges which could cause damage to rigging equipment must be?

Guarded

278

Wooden scaffolding must be made of ______ ______ lumber and must have a strength _____ times the weight of the load.

Unpainted, dressed lumber and a strength 4 times the weight of the load.

279

True or False: A trench is defined as an elongated dug out area of ground whose depth is equal to its width at the bottom.

False

280

True or False: All ingredients of the controlled product are listed in the MSDS?

False