Newfoundland & Labrador: Welding Fume Regulations & Exposure Limits

Last updated in June 2024

We have been a pioneer in North America, providing welding fume extraction solutions since the 1980s. In this blog post, you will find the exposure limits in Newfoundland and Labrador for some of the most common hazardous metals and gases found in welding fume.

Fumes are formed when a metal is heated above its boiling point, and its vapors condense into very fine particles. Their size ranges from 0.005 to 20 µm, but most are smaller than 1 µm and may deposit throughout the respiratory system.

The fume composition depends on the material being welded, the electrode, the coatings, the flux, and the shielding gas, among other things. Air sampling is usually necessary to know which hazardous and regulated substances are in your working environment. But getting information on the composition of metals, gases, and consumables used in the welding process is usually a good start.

What particulates are potentially dangerous in welding fume?

Here is a list of some dangerous metals and gases commonly found in welding fume that will be covered on this page:

• Aluminum
• Antimony
• Arsenic
• Beryllium
• Cadmium
• Chromium
• Cobalt
• Copper
• Iron oxide
• Lead
• Manganese (learn more about manganese in welding fumes)
• Molybdenum
• Nickel
• Silver
• Tin
• Titanium dioxide
• Vanadium
• Zinc
• Argon
• Carbon Dioxide
• Carbon Monoxide
• Helium
• Hydrogen Fluoride
• Nitric Oxide
• Nitrogen
• Nitrogen Dioxide
• Ozone
• Phosgene

Newfoundland and Labrador Occupational Health and Safety Regulations – Welding Fume

In Newfoundland and Labrador, companies must follow the Occupational Health and Safety Regulations under the Occupational Health and Safety Act.

Information regarding Exposure Limits can be found in Part 6 (Occupational Health Requirements). However, here are a few essential parts regarding welding fume, metals, and gases.

“An employer shall ensure that
(a)  atmospheric contamination of the workplace by hazardous substances is kept as low as is reasonably practicable;
(b)  a worker is informed of the nature and degree of health effects of the hazardous substances to which the worker is exposed;
(c)  exposure of a worker to hazardous substances is as minimal as is reasonably practicable, and where a threshold limit value has been established by the ACGIH, exposure shall not exceed the threshold limit value;
(d)  except as otherwise determined by the division, a worker is not exposed to a substance that exceeds the ceiling limit, short-term exposure limit, or 8-hour TWA (time-weighted average) limit prescribed by ACGIH; and
(e)  where a substance referred to in paragraph (d) has an 8-hour TWA limit, a worker’s exposure to the substance does not exceed
        (i)  3 times the 8-hour TWA limit for more than a total of 30 minutes during the work period, and
        (ii)  5 times the 8-hour TWA limit.”

“TLV means the documentation of threshold limit values for chemical substances and physical agents in the work environment published annually or more frequently by the ACGIH.”

“ACGIH means the American Conference of Governmental Industrial Hygienists.”

Welding regulations can be found in Part 21 (Welding, Burning, and Cutting Operations). In addition, article 454 is specifically about ventilation.

“Effective local exhaust ventilation shall be used at a fixed work station to minimize worker exposure to harmful air contaminants produced by welding, burning or soldering.”

Regarding general ventilation, although not explicitly stated, the general consensus is that a minimum of 4 air changes per hour is required for industrial buildings, including those with welding operations. In confined spaces, the minimum recommended is 10 air changes per hour, though 20 or more may be necessary.

Any questions? Ask them directly in the chat at the bottom right of your screen or during one of our webinars.

Newfoundland and Labrador – Threshold Limit Values for Welding Fume, Metals, and Gases

Threshold Limit Values (TLV) are copyrighted by ACGIH and cannot be reproduced on other websites. However, you will find the links to the relevant pages on their website below. Use them to know the Exposure Limits to follow.

ACGIH has not published a recommendation regarding welding fumes in general. Therefore, they fall under the Particulates Not Otherwise Regulated category. The ACGIH recommendation, in this case, is a TLV-TWA of 3mg/m3 for respirable particles and 10mg/m3 for inhalable particles.

• Aluminum
• Antimony
• Arsenic
• Beryllium
• Cadmium
• Chromium
• Cobalt
• Copper
• Iron Oxide
• Lead
• Manganese
• Molybdenum
• Nickel
• Silver
• Tin, organic
• Tin oxide & inorganic
• Titanium
• Vanadium
• Zinc Oxide
• Argon*
• Carbon Dioxide
• Carbon Monoxide
• Helium*
• Hydrogen Fluoride
• Nitric Oxide
• Nitrogen*
• Nitrogen Dioxide
• Ozone
• Phosgene

* A concentration limit is not included because available oxygen is the limiting factor.

Health risks associated with breathing welding fumes

According to OSHA, the Centers for Disease Control and Prevention, the International Agency for Research on Cancer, and the CNESST (Quebec), breathing welding fumes could cause the following health effects:

• Eye, nose, and throat irritation
• Dizziness and nausea
• Breathing difficulties that could lead to suffocation or asphyxiation
• Metal fume fever
• Lung damage and various types of cancer
• Stomach ulcers
• Kidney damage
• Nervous system damage
• Manganism
• Chest pain
• Asthma
• Bleedings
• Dermatitis or eczema
• Kidney disease
• Bone and joint disorders
• Siderosis (iron oxide in lung tissue after inhalation)
• Stannosis (tin oxide in lung tissue after inhalation)
• Anthracosis (poisoning after inhalation of carbon dust)
• Berylliosis (poisoning after inhalation of beryllium dust)
• Accumulation of fluid in the lungs

These are good reasons to protect welders, meet the standards, and even extract pollutants as efficiently as possible. Welding fume extractors will be the best way to do so.

To learn more about welding fume regulations in another Canadian province or territory, feel free to use one of the links below to be directed to our article on the subject:

• Alberta
• British Columbia
• Manitoba
• New Brunswick
• Northwest Territories
• Nova Scotia
• Nunavut
• Ontario
• Prince Edward Island
• Quebec
• Saskatchewan
• Yukon