Welding Fume Regulations and Exposure Limits in Alberta

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 applicable in Alberta 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

Alberta Occupational Health and Safety Code – Welding Fume

In Alberta, employers are required to follow the Occupational Health and Safety Code. Occupational Exposure Limits can be found in Schedule 1. Here is some important information.

“An employer must ensure that a worker’s exposure to any substance listed in Schedule 1, Table 2 does not exceed its occupational exposure limits listed in Schedule 1, Table 2.”

“If no occupational exposure limit is established for a harmful substance present at a work site, an employer must ensure that a worker’s exposure to that substance is kept as low as reasonably achievable.”

“If no 15-minute occupational exposure limit or ceiling occupational exposure limit is listed for a substance in Schedule 1, Table 2, the employer must comply with the 8-hour occupational exposure limit, and ensure that a worker’s exposure to that substance does not exceed 3 times the 8-hour occupational exposure limit for more than a total of 30 minutes during a continuous 24-hour period, and 5 times the 8-hour occupational exposure limit, or the concentration that is immediately dangerous to life and health, whichever is lower.”

Alberta – Occupational Exposure Limits for Welding Fume, Metals, and Gases

Based on the Occupational Health and Safety Code, the following limits are the applicable Occupational Exposure Limits (OEL) in Alberta for welding fume and some of its components.

Abbreviations used in the tables below:

• ALARA: Exposure must be kept As Low As Reasonably Achievable
• TWA: The Time-Weighted Average concentration for an 8-hour workday
• STEL: Short-Term Exposure Limit (maximum time-weighted average concentration for 15 minutes, no more than four times per day, with at least 60 minutes in between)
• C: Ceiling (concentration never to be exceeded)
• (r): Respirable dust (smaller than 4 µm)
• (t): Total dust

OEL	TWA	STEL	C
Welding Fumes	ALARA	ALARA	ALARA

OEL	TWA	STEL	C
Aluminum	10mg/m3	None	None
Antimony	0.5mg/m3	None	None
Arsenic	0.01mg/m3	None	None
Beryllium	2µg/m3	0.01mg/m3	None
Cadmium	0.01mg/m3	None	None
Cadmium compounds	2µg/m3(r)	None	None
Chromium metal & (III)	0.5mg/m3	None	None
Chromium (VI)	0.01mg/m3	None	None
Cobalt	0.02mg/m3	None	None
Copper	0.2mg/m3	None	None
Iron Oxide	5mg/m3	None	None
Lead	0.05mg/m3	None	None
Manganese	0.2mg/m3	None	None
Molybdenum	3mg/m3(r) 10mg/m3(t)	None	None
Nickel	1.5mg/m3	None	None
Silver	0.1mg/m3	None	None
Tin metal & oxide	2mg/m3	None	None
Titanium dioxide	10mg/m3	None	None
Vanadium pentoxide	0.05mg/m3	None	None
Zinc oxide	2mg/m3	10mg/m3	None

OEL	TWA	STEL	C
Argon*	None	None	None
Carbon Dioxide	5,000ppm	30,000ppm	None
Carbon Monoxide	25ppm	None	None
Helium*	None	None	None
Hydrogen Fluoride	0.5ppm	None	2ppm
Nitric Oxide	25ppm	None	None
Nitrogen*	None	None	None
Nitrogen Dioxide	3ppm	5ppm	None
Ozone	0.1ppm	0.3ppm	None
Phosgene	0.1ppm	None	None

As a reminder, according to the Code, if no 15-minute occupational exposure limit or ceiling occupational exposure limit is listed, the employer must ensure that a worker’s exposure does not exceed 3 times the 8-hour occupational exposure limit for more than a total of 30 minutes during a continuous 24-hour period, and 5 times the 8-hour occupational exposure limit.

ACGIH – Threshold Limit Values for Welding Fume, Metals, and Gases

The American Conference of Governmental Industrial Hygienists (ACGIH) is an important organization researching hazardous substances and recommending exposure limits. They influence most health and safety organizations in North America, and knowing their recommended Threshold Limit Values (TLV) is very valuable.

Threshold Limit Values 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.

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-TWAEV 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:

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