The government is eager to increase drug testing in ‘safety critical' workplaces such as building sites. But what does this mean for employees' rights and responsibilities?

I work on a building site. My employer has asked me to provide a urine sample as it wishes to test for drug use. Do I have to co-operate?

If you have a written employment contract, look to see if you have agreed to provide a sample if requested. If so, you should give the sample. If you do not, you might be sacked without notice.

If you have no written contract, and you have not provided a sample to your employer in the past, you cannot be forced to provide a sample, but the consequences of refusing may be serious. If you work in an environment in which you could endanger yourself or others if under the influence of drink or drugs, your employer may be required to test its workforce to comply with its health and safety obligations or its customers' demands. Therefore, unless your employer can reassign you to an area of work in which testing is not required, it may have to dismiss you.

A familiar story

The above example illustrates the growing extent to which construction companies are testing for the use of alcohol and illegal drugs among their workforce. The government has encouraged this, stating that it believes that in "safety critical" industries, employers should be testing their workers.

Employees found to be under the influence of drugs or alcohol at work risk dismissal. Employers are, in one sense, in an even less enviable position. If they dismiss employees in these circumstances they are at risk of costly employment tribunal claims, but if they fail to do so they risk breaching health and safety laws, losing customers and even putting lives at risk.

The employee's side

Employees may feel blood or urine testing offends their dignity, and, understandably, employees may also believe that what they do off duty is their own affair. But if off-duty conduct leaves alcohol or drugs in an employee's system, and if they may make them a danger to themselves or others, they may again be at risk of dismissal.

Similarly, an employee seen drunk on a building site, even if off-duty, may fairly be dismissed if their conduct might undermine the confidence of safety inspectors or the public in the employer.

The employer's side

Employers should seek an employee's written consent before carrying out testing. Forcing a test on an unwilling employee could amount to an assault, and could also entitle an employee to resign and claim constructive unfair dismissal.

The consent sought from an employee should cover not only testing itself but also subsequent recording, use and disclosure of test results. The employer should emphasise that blood and urine samples provided under the testing procedure will be used to look for alcohol and performance-affecting drugs only.

If an employee tests positive, an employer should carry out a thorough investigation before taking any disciplinary action. This should include asking the employee whether they have any explanation for the failed test. For instance, it is unlikely to be fair to dismiss an employee whose drink has been spiked. An employer should also look into whether there may be mitigating circumstances, such as a medical condition such as depression that makes an employee susceptible to alcohol. Dismissing an employee in these circumstances could even give rise to a claim for disability discrimination as well as unfair dismissal.

With health and safety lapses in construction making the headlines increasingly frequently, it is clear that the issue of drug and alcohol use will not go away. It is therefore vital to be aware of your rights and responsibilities.

Edward Goodwyn is a partner in Masons' employment group. If you have a legal query about your employment, email us at