| Design feature |
Recommendations |
| National Fire Code of Canada 2010 |
- Refers to acceptable solutions for
- Indoor and Outdoor Storage: Division B, Part 3
- Flammable and Combustible Liquids: Division B, Part 4
- Install acceptable provisions for electric bonding to prevent static as per NFCC.
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| Tanks |
- Engineer construction materials and dimensions in accordance with chemical suppliers and applicable codes and standards (potential standardsFootnote1: ASME, CSA and API standards.
- Provide tanks in sound physical condition, with no rust or serious physical damage. Tanks must be certified and deemed suitable for the intended use by an external accredited testing company or agency.
- Mount tanks on containment pad surfaces.
- Subsurface storage tanks should not be used
- Mount tanks in stable positions and anchor securely.
- Locate tanks within a dyked area.
- Shelter from the weather (where appropriate) and protect from mechanical impact, vandalism.
- Protect against freezing (as recommended for external tanks).
- Provide means for detecting leaks in insulated tanks (e.g. identify inspection points, undertake regular leakage tests).
- Evaluate and provide means of controlling contaminated surface waters (e.g. roofing of tanks, runoff water treatment).
- Vent interior tanks to the exterior or into a dedicated overflow tank (never vent directly into the workplace):
- protect vents against release of entrained liquids or overflow (e.g. direct overflow piping to sumps or containment areas).
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| Location |
- Provide safe, easy access to the mixing area (design to contain and facilitate cleanup of spills, dust/flakes lost during transit to the mixing area).
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| Ventilation |
- Provide adequate ventilation for routine operations and emergency situations.
- Provide appropriate measures to control vapours in enclosed buildings (e.g. water spray and/or ventilation)
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| Spill containment |
- Install impervious, structurally sound floors.
- Provide structurally sound dykes, seal all joints.
- Provide a dyked containment volume capability of 110% of the volume for a single tank, and in multiple tank containment provide 100% of the largest tank plus 10% of the aggregate volume of the remaining tanks or 110% of the largest tank, whichever is greater (11).
- Engineer containment for long-term integrity (leak-proof for infiltration and exfiltration).
- Provide either an impermeable top coat to floors and dykes or a liner under the containment area.
- Evaluate and provide means for detecting subsurface leakage from containment systems.
- Provide for directing all spills, washes and infiltrating water to tanks (contaminated liquids must be treated to applicable limit before discharge).
- Provide effective capability for transferring spilled liquids from containment areas.
- Provide surface drainage to prevent pooling of minor spills and washdowns.
- Design to minimize tracking of fluids from containment surfaces.
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| Piping and valves |
- Design according to applicable codes.
- Waterlines must comply with all applicable local codes
- Use rigid, permanent piping throughout.
- Provide visible, accessible piping with a simple layout (to facilitate early leak detection and easy repair).
- Maximize above-floor piping or open containment channels for subgrade piping. Do not bury piping!
- Water supply lines are to be connected to the top of tanks above the high-level alarm sensor.
- Piping systems for material and dimensions must be properly engineered.
- Identify piping systems and valves (e.g. by labelling and/or colour coding).
- Provide mechanical impact protection for vulnerable exposed piping.
- Provide freezing protection for piping as required.
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| Backflow prevention |
- Design to protect against inadvertent transfers to/from interconnected tanks.
- Install backflow preventers on all waterlines at plant entry.
- Use top entry of waterlines to tanks (as secondary backflow prevention).
- Waterlines must comply with all applicable local codes
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| Drip containment |
- Provide local collection/containment (isolated from large containment areas) at drip points (e.g. under pumps, valves, flanges).
- Store in a paved/concrete, curbed or dyked area with no floor drains:
- provide containment capacity for the worst-event spill (no fewer than 4 drums)
- provide for effective cleanup (including recovery of washdown water) in the event of a spill.
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| Surfaces |
- Seal surfaces and joints to facilitate cleaning and surface impermeability.
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| Spill prevention/ detection |
- Install reliable, accurate level indicators on all tanks.
- Provide mechanical impact protection on glass sight gauges (including provision for containing and stopping release from broken gauge tubes).
- Install shut-off valves on all rupturable lines and tank gauges.
- Install permanent overflow piping from tanks directly to a definitive contained area.
- Install reliable, independent high-level alarms on tanks (visual and audible alarm).
- Interlock high-level alarms to tank feed pump (auto shut-off).
- Consider installation of 24-hour monitoring alarms (with remote) for immediate detection of major spills or immediate detection of tank or pipe rupture.
- Install emergency manual alarm button at potential major spill points.
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| Shelter |
- The preferred location for tanks containing aqueous liquids (all solutions) is in an interior centralized process area.
- The preferred location for oil-type liquids is in an exterior centralized tank farm area.
- If possible, roof exterior tank farms to minimize the quantity of infiltrating precipitation.
- Provide storage in an enclosed, secure area, segregated from other chemicals for drummed liquids
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| Security |
- Provide security precautions to prevent vandalism or access by unauthorized persons.
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| Emergency response |
- Provide accessible storage for spill response equipment, absorbents and personal protection equipment.
- Provide appropriate measures for fire detection and suppression, as well as for rapid, effective fire control with containment of liquid firefighting residues and treatment to required limits before discharge.
- Provide appropriate signalization of fire control equipment.
- Install a telephone or other voice communication system and manual alarm switch near the off-loading area.
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