WESTERN AUSTRALIA – Kewdale Drug Testing

Sue Caswell – General Manager

Paul Crawford – Operations Manager​

Sue moved to WA from New Zealand in 2008, bringing with her an extensive background and comprehensive qualifications in occupational health and safety, quality assurance, human resources and general management.

Specialising in civil construction, with contracting stints in a range of other industries Sue can offer new and existing TDDA clients an empathetic and practical approach to the management of drug and alcohol policies, training and testing.

Joining Sue in the Kewdale region, Victoria Park to High Wycombe and metro wide, is Paul Crawford.

Paul spent in excess of 18 years in counter terrorism, policing and traffic in Northern Ireland before moving to WA. He initially took up a role with the Perth Transit Authority and then moved to the WA police. Extending his skills to include occupational health and safety management, Paul then worked for 6 years in mining in the Pilbara. The wide diversity of people and industries he has interacted with in his previous roles has enabled him to have a comprehensive understanding of the challenges, particularly with drug and alcohol use, abuse and management, and how the outcomes of poor choices of individuals effect the workplace and the wider community. With his primary focus being operations across the South Perth and Kewdale territories, Paul is also the franchisee for Kewdale.

Sue and Paul have a wealth of combined experience and qualifications which will add value to the effective running of your business.

NOR (north of the river) or SOR (south of the river)  we can use our experience and knowledge to advise and guide new and existing TDDA clients through the challenges of mitigating the risk to your business from the use and abuse of drugs and alcohol.

TDDA has Western Australia covered right up to Port Hedland and Broome in the north down to the south of the state. Our purpose fitted mobile vans can come to your site saving you lost production and time when an employee needs a drug test either after an accident or even for pre-employment testing.

We are specialists in drug and alcohol training and can equip your managers and supervisors with  skill sets designed to help them specifically with reasonable cause or for cause drug and alcohol testing.

Our vans can be seen on a daily basis in and around key industrial areas like Henderson, Mandurah, Kwinana, Rockingham, AMC, Kewdale, Welshpool, Forrestfield,  and we frequently send teams to test for clients in Geraldton,  Dampier, Karratha, Port Hedland and Broome. We can also travel inland to places like Kalgoorlie and beyond.

Twenty four hours a day, 7 days a week, we can be available. We service the needs of our customers when everyone else is closed 24/7 and we can come to you.

Our services include drug and alcohol testing, using urinalysis or oral fluid (saliva) and breath alcohol for workplaces, and we are leaders in hair shaft testing (this is often referred to incorrectly as hair follicle testing) for family court and other legal matters.

Everything can be offered at our office in Bibra lake or via our mobile services.

We are locally owned and operated and travel anywhere between Joondalup and Dawesville without charging mileage and if you need us to go into the Pilbara or other regions we can negotiate a fair and reasonable travel rate.

We specialise in drug and alcohol policy development, education and testing. We have vast local and international expertise in health, safety, HR and law enforcement, most recently in the Perth metro and WA northwest.

As business owners ourselves, we can work efficiently and cost effectively with you to mitigate the risk, that drug and alcohol abuse is, to your organisation.

We know WA and we have colleagues interstate and in New Zealand if your organisation requires testing other than in Western Australia.

Contact Us


78 Discovery Drive
Bibra Lake
WA 6163

Postal Address

PO Box 1601
Bibra Lake DC
WA 6965

Sue Caswell

Sue Caswell

General Manager

Mobile: +61 41 267 4648

Paul Crawford

Paul Crawford

Operations manager

Mobile: +61 427 919 065

TDDA Kewdale are members of:

•Safety Institute of Australia


Hair Follicle Testing v Hair Shaft Testing

Hair testing is normally used to determine persistent drug use.

The testing procedure is often incorrectly referred to as hair follicle testing which is in fact a procedure used by investigators to determine someone’s DNA or genetic blueprint.

Hair shaft testing, however, is used to determine compounds and metabolites which have entered the human body via inhalation, ingestion, injection and even through the skin.

Hair shaft testing is the most effective way to detect if for example someone is using illicit drugs on an ongoing basis as part of their lifestyle or if prescribed medications are being used in excess of the recommended dose.

This type of testing can be used for pre-employment testing and helps employers work through due diligence on new hires and contractors that will potentially join the team.

It can also be used by the Courts in custody cases and TDDA has been conducting testing for the Court of Western Australia for several years now.

At TDDA we aim to educate and train, as well as conduct testing, in our journey to help create drug free communities.

If you have specific questions, please call us directly but meanwhile refer below for answers to some commonly asked questions we receive:

Where is the hair taken from?
Either head hair or body hair can be used however the sample cannot be a mixture of both head and body hair.

What steps do you take to identify a person completing a hair test?
They are required to identify themselves with photo identification (ID) e.g. a driver’s licence or passport. The technician checks the ID photo to make sure it is the person that the sample is to be collected from and records the description of the ID and ID number on the chain of custody form (CCF). The ID used is reported with results.

What are the steps between taking a sample and that sample being tested by the laboratory to ensure the sample is not tampered with?

The hair sample is placed into an envelope in front of the donor, sealed with a tamper proof/security seal and then signed by the donor. The security envelope and corresponding signature are checked upon receipt at the lab to ensure they are intact.

Can the accuracy of results be affected if a person bleaches or dyes their hair?

There are currently no known successful commercial adulterants for hair tests and the recommended use of normal hair care products/procedures do not have a significant effect on results.

Are there circumstances where you or the laboratory would refuse to proceed to test a hair sample?

The most common reasons a sample is not analysed include:
• Chain of custody on the sample is not intact, e.g. security seal not on envelope, no identification on sample envelope, names/ID mismatch
• Quantity of sample submitted was not sufficient for analysis
• The hair is identified to not be human hair
• The root end cannot be identified

If a result is under the allowed amount, is it returned as positive or negative?
A result that is below the Omega Laboratories established cut off levels would be reported as Negative

How can a positive result for methamphetamine be followed by a clear test 10 days later?

Hair collected from the head at different time frames can yield differing test results due to factors such as hair growth rates, dormant hair affects and how close to the scalp each specimen was collected.

Can the validity of a hair sample be compromised if the person taking it mistakenly cuts the sample from the wrong end of the hair (not the scalp end) so the results are not from the most recent 3 month period but from an earlier period of time?

It is possible and we have seen photographic evidence of samples taken where the hair was cut well away from the scalp which would result in the test being carried out for an incorrect timeframe. TDDA collection technicians undergo specific hair collection training prior to being able to collect hair samples.

Are you able to comment on how long a substance stays in the body generally?

This varies. An individual’s metabolism, body mass, age, hydration level, physical activity and health conditions all factor in the length of time substances remain in the body.

What is the significance of the different levels of results for a substance mean in terms of usage?

The laboratory is not in a position to determine usage and can only state whether or not the drug and/or metabolite was present in the sample. The amount of drug detected cannot be directly correlated with an amount of drug ingested due to factors such as drug purity, different hair growth rates, age and varying metabolic rates.

When does drug usage need to have taken place prior to testing to be detected in the results? Is this likely to be a range of dates or a particular point in time? 

This is dependent upon the actual growth rate of an individual’s head hair and past drug history.


New State of the Art Drug Testing Devices

TDDA launches three new state-of-the-art workplace testing products.

At TDDA we’re always on the lookout for ways to make workplaces safer and more efficient. I’m delighted to tell you that we’ll be introducing three new technologies that do just that.

These new tests will detect a wider array of drugs more accurately. That means getting reliable, up to date testing results with less disruption in the workplace.

When we looked at TDDA testing data a few things stood out. We needed to deliver a best in class oral fluid testing product and address the issue of prescription opiates and synthetic cannabinoids.

With the recent release of the new oral fluid drug testing standard (AS/NZS 4760:2019), oral fluid testing is a hot topic both in Australia and New Zealand. To maintain our leadership in this space we’re introducing the ToxWipe™ 7.

TDDA has secured access to this new device that provides fast, accurate and effective oral screening. It detects up to 7 commonly abused drugs one of the most comprehensive on-site screening devices currently on the Australasian market.

These include:
• Amphetamine Type Substances
• Cannabinoids
• Cocaine and Metabolites
• Opiates
• Oxycodone
• Benzodiazepines*

*Not included in AS/NZS 4760:2019

Featuring the latest generation antibodies for improved performance and sensitivity, the ToxWipe™ 7 produces accurate results and only requires a small sample volume. This helps to reduce the impact of ‘dry mouth’, a common problem with oral fluid collection caused by a lack of available saliva.

The new ToxWipe™ 7 is compliant with the new AS/NZS 4760:2019 and available now!

In September, Australia and New Zealand will have exclusive access to the TDDA 7 Panel Urine Screen Cup. It’s is the first screening cup featuring a new Oxycodone strip.

Opiates and opioids remain a growing issue, you need only to look to America or Australia to see the problems prescription painkillers, legally obtained or otherwise, can cause for employers. The commonly prescribed Oxycodone did not produce a positive response in routine drug screens until now.

Compliant under Appendix B of the AS/NZS 4308:2008 Standard, TDDA’s new 7 Panel Urine Screen Cup will be a compliant and reliable way of detecting employees on Oxycodone in the workplace.

Due to the ever changing compounds in Synthetic Cannabinoids, we have to constantly scan the markets in order to detect the latest developments. TDDA now offers the most comprehensive testing utilising three different and unique drug types for detection in one easy to use device. TDDA’s new 3 Panel Synthetic Cannabis Dip Test is used in addition to urine testing and detects the synthetic cannabinoids JWH-018, JWH-073, AB-Pinaca, AB-Fubinaca and UR-144 5-Pentanoic Acid. It’s available from July, and is an extremely effective way to keep this ever emerging drug group from negatively impacting on your business.

TDDA is committed to delivering the best advice, policies, training and testing throughout Australasia. Our new tests are a demonstration to this commitment and we hope you reach out, ask some questions and let us show you our new products and services.

If you’re interested in a demonstration or want to learn more, please reach out to your TDDA representative or go to www.tdda.com to find your nearest office.

TDDA has ISO15189:2012 accreditation for workplace drug testing (see NATA and IANZ websites for further detail). TDDA is a drug and alcohol testing, education and training leader with more than 64 locations throughout Australasia. www.tdda.com

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