On-site visits, chemical tests and quality certificates are means of making sure your supply chain follows your standards.
Require certificates of compliance
The easiest way to get started is to ask your supplier to provide information on the chemicals used in the production process. Ask for the Material Safety Data Sheets (MSDS) or certificates of quality for the chemicals used. Such information must always be available to the supplier since it is mandatory to provide an MSDS with a shipment of chemicals.
If your supplier is certified by a specific certification body, you should ask for their licence number or certificate number and verify its authenticity with the issuing body. This, you can often do online.
Test to verify
Based on your supplier agreement, which specifies how your fabrics should be produced and which chemicals should be excluded; you may want to carry out tests to verify actual compliance. Asking for third-party testing by an accredited laboratory before shipment is the easiest way.
However, it is important to be aware that there are many false test reports and other false documents in circulation, and you should be critical when checking these documents. There is always the possibility of contacting the test lab or the certification company directly to verify authenticity.
So if a certain article or range of articles is very important to your company, you should consider performing your own testing when your products are delivered. There are numerous cases where, despite on-site testing, simple mistakes in the production phase, as well as instances of fraud, have had a severe impact on companies, damaging their reputations and having sizeable financial effects.
When selecting substances and products for testing it is always good to start with the lowest-hanging fruit – tests that identify important substances, and that are cheap and simple to perform. Good examples of low-hanging fruit are testing for the presence of specific chemical elements (atoms) such as heavy metals or chlorine, which indicates the use of PVC. Such tests can easily be done using non-destructive techniques such as XRF. You simply hold the product you want to test in front of an XRF “gun” for a few minutes and get an instant answer. For more advanced tests on specific substances or the exact composition, you might need to contact external laboratories.
Understand the information you get
– MSDS and other documents
Sometimes the information received from suppliers, such as MSDS, test reports and letters of conformity can be difficult to understand due to their technical nature.
In short, an MSDS provides the information needed to assess the risks and hazards associated with a specific chemical, chemical product or formulation. It states the name of the product, the composition of the ingredients (if more than one), any specific hazards connected with the product and what to do in case of a spillage, accident, fire or other emergencies.
Also test reports from your own tests or third-party laboratories can be tricky to understand. Here are a couple of things you should be wary of:
- Test results – the measured content of a specific substance. Check the units used; common units are g/kg, mg/g, mg/kg, mg/l, ppm, %, ‰, %W/W, %V/V.
- Detection limit – make sure it is not higher than your acceptable limit for the relevant goods. Check the units used.
- Reproducibility – all tests that are performed involve some uncertainty over the results. This may be +/- 1% or it may be +/-50%. This means that if two different labs do the same test on the same product they should receive the same results within the margin of error of 1% (or 50%). Both tests could actually be correct even if seemingly quite different. A problem could arise if the first test says a product is OK but a second test says the opposite. Extra care should be taken if the test results are close to the acceptable limit for approval, especially if the test method has a wide reproducibility.
- Repeatability – very similar to reproducibility. Repeatability is only verified for the same laboratory, staff and equipment. The uncertainty for repeatability is smaller than for reproducibility.
- Test method – if you have specified that a certain test method should be used, make sure the lab has used that specific method. If not, the difference between them must be explained so you can ascertain if the results are reliable for your needs.
On-site verification of compliance
The most advanced way of assuring compliance is through auditing of the production site, either by inspections carried out by your own staff or by third parties. It is not possible to go into details of how auditing should be performed since it depends on the process, the supplier and the purchase agreement.