Pennsylvania drug testing laws for employers: pre-employment testing rules (2026)

Pennsylvania employers can generally drug test job applicants, and the state-level limits on what they do with the result come mainly from the Medical Marijuana Act. As of October 2026, an employer may not refuse to hire someone solely because they are certified to use medical marijuana, but it need not allow use at work and may keep a patient who is under the influence out of listed safety duties. In Philadelphia, a city ordinance in force since January 1, 2022 bars most pre-employment marijuana testing, and DOT-regulated roles in the state follow federal testing rules.

Does Pennsylvania have a drug testing law for private employers?

We did not find a Pennsylvania statute that sets procedures for private-employer drug tests the way Iowa's or Maine's laws do, so for most private employers the procedural safeguards come from their own written policy, their laboratory and, for regulated roles, federal rules. What Pennsylvania does regulate is the hiring decision when medical marijuana is involved, in the Medical Marijuana Act (Act 16 of 2016). Philadelphia adds a pre-hire testing ban, and federal law governs transportation roles and federal contractors.

That makes a written policy more important, not less. Without statutory steps to point to, the policy is the record of what you told the candidate, which drugs you test for, how a positive is confirmed and reviewed, and what happens next. The pre-employment drug testing policy template covers those clauses.

What does the Medical Marijuana Act mean for hiring?

Section 2103(b) of the act has three parts:

1. No discrimination for certified status. No employer may discharge, threaten, refuse to hire or otherwise discriminate or retaliate against an employee regarding compensation, terms, conditions, location or privileges solely on the basis of the person's status as an individual certified to use medical marijuana.
2. No duty to accommodate use at work. The act does not require an employer to accommodate medical marijuana use on its property or premises, and does not limit discipline of an employee for being under the influence in the workplace or for working under the influence when the employee's conduct falls below the standard of care for the position.
3. Federal law wins. The act does not require an employer to do anything that would put it in violation of federal law.

The protection is written around certified status, not around every positive test result. A candidate who is a certified patient will usually test positive for THC, so decide in advance how your policy handles that, and route the result through your medical review officer rather than asking about medical conditions yourself. The EEOC's guidance allows an employer to ask about lawful medications after a positive test to validate the result; see pre-employment medical exams under the ADA.

Which jobs can be closed to patients under the influence?

Section 510 of the act lists prohibitions that work like safety-sensitive carve-outs:

• A patient may not operate or be in physical control of chemicals that require a federal or state permit, or high-voltage electricity or another public utility, while under the influence with more than 10 nanograms of active THC per milliliter of blood.
• A patient may not perform employment duties at heights or in confined spaces, including mining, while under the influence of medical marijuana.
• An employer may prohibit a patient under the influence from any task the employer deems life-threatening to the employee or co-workers, and from any duty that could create a public health or safety risk. The act says such a prohibition is not an adverse employment decision, even if the patient loses pay.

For hiring, write the duties of each tested role into the job description, so that a section 510 restriction ties to a documented duty rather than to the person's status.

Does Philadelphia ban pre-employment marijuana tests?

Yes, for most jobs. Philadelphia Code chapter 9-5500, "Prohibition on Testing for Marijuana as a Condition for Employment", took effect January 1, 2022. The Philadelphia Commission on Human Relations explains that it applies to prospective employees, that testing current employees is still permitted, and that pre-employment marijuana testing remains allowed where:

• a federal or state statute or regulation requires it for safety or security;
• the federal government requires it as a condition of a contract or grant;
• a collective bargaining agreement provides for it; or
• the employee's work could significantly affect others' health or safety, such as law enforcement, medicine or construction. The current list of exceptions is in section 9-5502.

A complaint must concern an incident in Philadelphia within the last 30 days. Employers hiring in the city can still test applicants for other drugs; take THC off the applicant panel for roles outside the exceptions.

Is recreational marijuana legal in Pennsylvania?

The employer-facing cannabis rules are those of the Medical Marijuana Act. The most recent adult-use bill to move, HB 1200, passed the House 102 to 101 on May 7, 2025; the Senate Law and Justice Committee voted 3 to 7 against reporting it on May 13, 2025, which the General Assembly lists as its last action. If adult-use legislation passes later, read its employment section before changing your policy.

Which federal rules still apply in Pennsylvania?

• DOT-regulated roles follow 49 CFR Part 40; a commercial driver needs a verified negative pre-employment result before the first safety-sensitive function (49 CFR 382.301). Pennsylvania's act yields to federal law, and Philadelphia's ban excepts tests required by law.
• Schedule III and DOT. The April 28, 2026 order moved FDA-approved and state-medical-license marijuana to Schedule III. DOT's Part 40 guidance (May 15, 2026) says a Pennsylvania patient certification still cannot make a DOT positive negative.
• Federal contractors need the policy statement and awareness program in the FAR Drug-Free Workplace clause, which also supports Philadelphia's contract exception where the contract requires testing.

What should staffing agencies placing workers in Pennsylvania do?

• Split the panel by location. For Philadelphia placements outside the exceptions, drop THC from the pre-assignment panel even if the client tests elsewhere in the state.
• Get the client's duties in writing. Section 510 restrictions and Philadelphia's health-and-safety exception both turn on what the worker will actually do; capture that in the job order.
• Keep certification out of the hiring file. Let the MRO handle medical explanations, and record only the cleared or not-cleared result.
• Check registration in Pennsylvania staffing agency licensing.

Pennsylvania drug testing laws at a glance

A checklist before you test a candidate in Pennsylvania

1. Write the policy: who is tested, when, the panel, confirmation and MRO review.
2. For Philadelphia roles, check section 9-5502 before including THC on an applicant panel.
3. Document safety duties for each tested role so section 510 limits attach to the job.
4. Route THC positives through the MRO and decide based on your written rule, not on certified status.
5. Keep DOT-covered drivers in a separate federal program.

For other states, read drug testing laws in hiring; for the rest of the Pennsylvania process, including Philadelphia's other hiring rules, see hiring employees in Pennsylvania.