Safety Office, Commissary Building
University of Waterloo
200 University Avenue West
Waterloo, Ontario, Canada N2L 3G1
Phone 519 888 4567 Ext. 33587
Fax 519 886 8082
Email: safety@uwaterloo.ca
To protect the health and safety of faculty, students, and staff from procedures that may cause the building's fire alarm system to be activated or create an unwarranted fire risk.
This program covers any University of Waterloo employee and contractors whose job duties involve hot work activities.
Permits are required for cutting, welding, or soldering in university owned buildings. Physical plant supplies, issues or may make arrangements for permits within a minimum of 48 hours prior notice.
Fill out this form to apply for a hot work permit.
Shops and teaching facilities for:
Nearly all metals generate fume and a few of the risks are listed below.
To reduce exposure to the various inhalation hazards associated with welding and cutting, adequate local and general ventilation is essential.
Welding areas should have good general ventilation (about 10 to 12 air changes per minute) that is not re-circulated back into the building.
Weld out of the plume. Use a tight fitting welding helmet to shield you from the plume.
A well-designed welding helmet can help reduce a welder's exposure to welding fumes by diverting the plume away from the welder's breathing zone.
Local ventilation should be used in conjunction with adequate general ventilation to reduce the amount of welding contaminants entering the area.
A downdraft bench has an open grid work surface. Air is drawn downward through the grid, drawing contaminants into exhaust ducting. Air speed must be great enough to keep contaminants from rising into your breathing zone. If work pieces are too large they may block the ventilation airflow or cause pockets of high velocity air (which could affect shielding gases).
Flexible ducting allows the capture hood to be moved where required. Provide an air velocity of at least 100 ft/min (0.5 m/s) across the welding arc. Place the hood as close as practical to the work. The optimal location for the hood is about 1 duct diameter from the arc.
All combustible material must kept more than 15 Meters from the welding or cutting process.
The following fire extinguishers must be available:
The requirements of section 5.2 of the W117.2-94 Safety in Welding, Cutting, and Allied Processes Standards must be well understood by the operators. The following is a brief summary of them.
Wear eye and face protection in welding workplace to protect against radiation and weld spatter. Appropriate eye and face protection shall be selected in accordance with CSA Standard Z94.3.
Electrode size | Arc current in ampere | Shade number |
---|---|---|
3/23 | Less than 60 | 7 |
3-5/32 | 60-160 | 10 |
5-8/32 | 160-250 | 12 |
8/32 | 250-550 | 14 |
Type of cutting | Material thickness in inches | Shade number |
---|---|---|
Light | Under 1 | 4 |
Medium | 1-6 | 5 |
Heavy | Over 6 | 6 |
See the Compressed Gas Standard for more information.
Safety Office, Commissary Building
University of Waterloo
200 University Avenue West
Waterloo, Ontario, Canada N2L 3G1
Phone 519 888 4567 Ext. 33587
Fax 519 886 8082
Email: safety@uwaterloo.ca
The University of Waterloo acknowledges that much of our work takes place on the traditional territory of the Neutral, Anishinaabeg and Haudenosaunee peoples. Our main campus is situated on the Haldimand Tract, the land granted to the Six Nations that includes six miles on each side of the Grand River. Our active work toward reconciliation takes place across our campuses through research, learning, teaching, and community building, and is centralized within our Office of Indigenous Relations.