Fire debris acceptance criteria and packaging guide
Overview
The Centre of Forensic Sciences (CFS) provides chemical analysis and physical comparisons of different types of materials and evidence, including fire evidence.
The chemistry section of the CFS does analysis of fire debris, and other items, for the presence of ignitable liquids, such as petroleum products, alcohols, solvents and oils.
There are specific ways you must package and submit fire debris evidence to the CFS for analysis.
Acceptance criteria
There are three categories of acceptance criteria when submitting fire debris to the Centre of Forensic Sciences for analysis.
Category 1
This category applies to fire cases involving:
- serious injury or death
- public safety
- possible linkage to more serious violent offences
- homicide
- attempted murder
- death investigation
- arson — disregard for human life (with serious injuries)
CFS scientific advisors will assess relevant information that submitter(s) provide to determine what evidence they accept for each case. The CFS advisors will discuss with the submitter(s) when necessary.
Evidence acceptance for each case will apply across all involved submitting agencies. Evidence from an accused or suspect will be considered on a case-by-case basis.
Category 2
This category applies to samples of debris used to help determine the origin and cause of the fire, and/or for investigative or litigative purposes.
For cases involving:
- arson — disregard for human life (minor or no injuries)
- arson — property
Two samples for initial analysis
We will accept a maximum of two items for initial analysis.
If you use glass mason jars to package samples, we will also accept an empty comparison mason jar as part of the submission. We will not count this empty jar as one of the two maximum. Analysis of the comparison jar will only take place if it is relevant for interpretation of the associated items.
Additional items
We may consider accepting additional evidence items based on case-specific circumstances and discussion with a chemistry scientific advisor. The submitter chooses items for ignitable liquids or hydrocarbon gases testing only.
We will consider additional evidence items, including:
- contents of fuel containers depending on the investigative or litigative need
- items from an accused or suspect on a case-by-case basis
We will not accept items for cellulosic fibre identification or plastic identification.
After the initial report
After we release the initial report, we may consider additional evidence items for testing. These additional testing requests must demonstrate an ongoing investigative or litigative need.
If comparison substrate samples have been collected, they may be considered for analysis depending on the initial report results.
Category 3
We will not accept items for arson — property cases where one or more of the following potential scenarios apply:
- clear video surveillance is available that demonstrates a fire has been deliberately set
- stolen/abandoned vehicle fires
- damage or attempted damage to structures not intended for human occupancy (for example fences, dumpsters)
- unexpected/out of place fuel containers located near the origin of the fire
Packaging guide
You must package samples in a specific way depending on the sample type. There are six sample types:
- fire debris
- large items (any items that cannot fit into a 1 litre mason jar)
- liquids
- soil, vegetation or food
- lung and biological tissue
- clothing
There are required and recommended packaging guidance for each sample type.
Fire debris
Required packaging method
Use glass mason jars with metal cap and ring, except for larger items and liquid samples (see below).
If alcohols, solvents or lacquer thinners are suspected to have been used, use glass mason jars only.
Recommended packaging guidance
- Leave air space for sampling (approximately ¾ full).
- Ensure the mouth of jar is clean of debris, and that the metal ring and lid are tightly sealed.
- Apply numbered, tamper-proof security seal to jar.
- Place protective netting over jar.
- Seal jar in a nylon bag if the item has a noticeable petroleum odour.
- Submit an empty jar for comparison purposes.
Large items (any items that cannot fit into a one litre mason jar)
Required packaging method
Only use specialty nylon bags.
We will not accept items for analysis if they are packaged in:
- garbage bags
- paper bags
- Ziploc bags
- standard police evidence bags
These bags are not suitable for retaining volatile ignitable liquid vapours.
Recommended packaging guidance
- Leave air space in bag to allow for sampling.
- Seal the bag using one of the following methods:
- “Swan neck” seal: twist neck of bag, fold over and secure with cable-tie or tape. Seal opening of nylon bag with duct tape.
- Fold the opening of the bag over on itself at least three times and seal with duct tape.
- Double-bag the item if it is heavy, very wet, has sharp edges or has a strong petroleum odour.
- Items in bags should be small enough to fit into a conventional microwave.
Liquids
Required packaging method
We must receive liquids upright with no visible signs of leakage. Ensure that lids are closed tightly.
Recommended packaging guidance
- Use glass vials (20 mL) with a foil lined lid.
- Ship liquid items separately from other items.
- If a mason jar must be used to package a liquid, submit no more than 50 mL (approximately 1/4 cup), and seal the jar in a nylon bag to prevent leakage.
Soil, vegetation or food
Required packaging method
Refrigerate the sample as soon as possible to reduce the possibility of bacterial action.
Lung and biological tissue
Required packaging method
Use only glass mason jars with a metal cap and ring. Jars must not be more than ¾ full.
All lung submissions must have an analysis request for either ignitable liquids and/or hydrocarbon gases (such as natural gas and propane).
Recommended packaging guidance
Submit an empty jar for comparison purposes.
Clothing
Required packaging method
Package suspect or victim clothing in glass mason jars or specialty nylon bags.
Store and ship suspect clothing in separate boxes from items recovered at the scene, including any items associated with a victim.
Recommended packaging guidance
Package suspect clothing within 24 hours of the occurrence. If you package clothing after 24 hours, contact the CFS chemistry section to discuss if the sample is suitable for examination.
Refrigerate victim clothing with biological fluid or tissue on it as soon as possible.
Comparison samples
Whenever possible, submit a comparison sample for analysis of:
- unburnt debris (for example unburnt carpet sample, wood, etc.)
- unused substrate used to collect a liquid (for example, a paper towel wipe)
This will help account for contributions made to the analytical results by the debris and substrate materials.
Packaging needs and suppliers
You can get most of the appropriate packaging supplies from retail kitchen or hardware stores and lab supply companies.
Mason jars (1 litre): Before you use jars to package samples:
- clean by rinsing with hot water (do not use soap)
- place rinsed jars upside down to dry away from potential sources of ignitable liquid vapour
- store cleaned jars with their lids-on until they are used
Specialty nylon bags: standard size is typically 12 x 18 inches.
Glass vials with foil-lined lid (20 ml size):
Polynet protective netting 2” to 4” diameter:
Contact us
For more information and guidance, including help with sourcing any of the above items, please contact the CFS chemistry scientific advisor: