Update on Risks and Control of Mould, Lead and Silica
on Construction Projects

- - Part 5 - -

Ministry Of Labour Guideline:

Lead on Construction Projects, 2004

Lead and lead compounds have had many important uses in construction and manufacturing. The major class of lead compounds of importance on construction projects is the inorganic lead compounds. These compounds may be toxic by routes of inhalation or by inadvertent ingestion, through transfer of dust from hands or food or drink to mouth. Some of the more important lead-containing materials that may be encountered on construction projects are listed below.

• Rust-resistant lead-based paint. Commonly present on bridges, structural steel, mechanical equipment, etc.
• Lead-based architectural paint.
• Lead sheeting, babbit, plugs, etc.
• Lead-containing pointing mortar.
• Lead dust and fume residue in factories where lead was used in the manufacturing process.

The disturbance of these materials on construction projects, especially by very disruptive operations such as abrasive blasting or hot cutting, creates potential exposures well exceeding current exposure limits.

The US Occupational Health and Safety Administration issued in 1994 a comprehensive regulation to address construction exposure to lead⁸ . To address these potentially harmful exposures in Ontario, the Ministry of Labour issued a guideline of work practices for control of lead on construction projects in September of 2004⁹ . These guidelines are not a regulation but do point towards the safety measures the Ministry is expecting. To quote the Foreword,

This Guideline has been prepared to assist persons, such as employers, construction project owners, constructors, contractors and subcontractors, who have duties under the Occupational Health and Safety Act (OHSA) and it regulations to protect workers from exposure to lead. It should not be taken to be a statement of the law or what is necessary to comply with the law. A person with legal duties may or may not agree with the Guideline and there is no legal requirement to follow the Guideline. It is for each such person to decide what is necessary to comply with the OHSA and its regulations.

A person who needs assistance in determining what constitutes compliance should consult with his or her legal advisor. Ministry inspectors will assess workplace situations against the relevant provisions of the OHSA and its regulations but they do no enforce the Guideline, although they may refer to it in determining whether the relevant laws have been complied with.

For the purpose of the Lead Guideline, lead exposures are classified as follows:

• Application of lead-containing coatings with a brush or roller.
• Removal of lead-containing coatings with a chemical gel or paste and fibrous laminated cloth wrap.
• Removal of lead-containing coatings or materials using a power tool that has an effective HEPA filtered dust collection system.
• Installation or removal of lead-containing sheet metal.
• Installation or removal of lead-containing packing, babbit or similar material.
• Removal of lead-containing coatings or materials using non-powered hand tools other than manual scraping or sanding.
• Soldering

• Welding or high temperature cutting of lead-containing coatings or materials outdoors. This operation is considered a Type 2a operation only if it is short-term, not repeated, and if the material has been stripped prior to welding or high temperature cutting. Otherwise, it would be considered a Type 3a operation.
• Removal of lead-containing coatings or materials by scraping or sanding using non-powered hand tools.
• Manual demolition of lead-painted plaster walls or building components by striking a wall with a sledgehammer or similar tool.

• Spray application of lead-containing coatings.

• Welding or high-temperature cutting of lead-containing coatings or materials indoors or in a confined space.
• Burning of a surface containing lead.
• Dry removal of lead-containing mortar using an electric or pneumatic cutting device.
• Removal of lead-containing coatings or materials using power tools without an effective HEPA filtered dust collection system.
• Demolition or cleanup of a facility where lead-containing products were manufactured.
• An operation that may expose a worker to lead dust, fume or mist that is not a Type 1, Type 2, or Type 3b operation.
  

• Abrasive blasting of lead-containing coatings or materials.
• Removal of lead-containing dust using an air mist extraction system.
• The following general precautions will apply to all Levels of Lead Work.
• Provide appropriate training.
• A medical surveillance program is highly recommended.
• Provide suitable washing facilities.
• Workers shall not eat, drink, chew gum or smoke in the lead work area.
• Drop sheets should be used below all lead operations that will produce dust, chips or debris.
• Dust and waste should be cleaned up and removed with a HEPA vacuum cleaner.
• Clean-up after every operation to prevent lead contamination.
• Dust and waste should be taken away in a sealed, labeled, sturdy container.
• The work area should be inspected daily to ensure clean.
• Compressed air or dry sweeping must not be used to clean up any lead-containing dust or waste from a work area or from clothing.
• (Although not a requirement of the Ministry of Labour Lead in Construction Guideline, the contractor should also comply with regulatory requirements for prevention of environmental pollution and waste disposal).

Type 1 Lead Work Practices

• Respirators are not required, but if requested must be provided, with the necessary fit-testing, training and maintenance.

Type 2 Lead Work Practices

• Post signs to warn of the lead hazard.
• Wear protective clothing and equipment.
• Where lead-containing paints or coatings are being applied by spraying, all workers shall wear Powered Air Purifying Respirators and high efficiency filters or supplied air respirator with hood helmet, operated in continuous flow mode.
• For all other Type 2 operations, wear a half-facepiece N95 respirator or better.

Type 3 Lead Work Practices

• Post signs to warn of the lead hazard.
• Barriers, partial enclosures or full enclosures shall be used to separate the work area from the remainder of the project and/or to protect the environment from airborne lead dust. For Type 3a operations indoors and removal of lead-containing dust using an air mist extraction system, barriers, partial enclosures or full enclosures shall be provided. For Type 3b operations indoors, and abrasive blasting operations conducted outdoors full enclosures should be provided.
• A worker decontamination facility should be provided for removal of lead coatings using uncontrolled power tools, demolition or clean-up of a facility where lead-containing products were manufactured, or abrasive blasting of lead coatings, or removal of lead-containing dust using an air mist extraction system. The decontamination facility shall have a dirty change room, shower and clean change room.
• Mechanically ventilate all enclosed work areas. Use local exhaust ventilation where possible.
• Wear protective clothing and equipment.
• Use respirator with a protection factor of 50, except for abrasive blasting operations for which a Type CE respirator operation in pressure demand or positive pressure mode shall be used. Ensure breathing air meets CSA Standard Z180.1-00 and where an oil-lubricated compressor is used, provide a continuous carbon monoxide monitor/alarm.

PEN # 19 "Update on Risks and Control of Mould,
Lead and Silica on Construction Projects"

continues with

PEN #19 "Update on Risks and Control of Mould, Lead and Silica on Construction Projects"

Bruce Stewart CIH, ROH
Senior Vice President
Pinchin Environmental Ltd.

Presented at Construction Superconference
Toronto, November 29, 2004

⁸ OSHA; Standard 29 CFR-1926.62, Lead Exposure in Construction; Occupational Health and Safety Administration, US Department of Labour, effective October 1993.

⁹ Ministry of Labour; Guideline: Lead on Construction Projects; Ontario Ministry of Labour; Toronto, 2004.

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