Custodian screening questions: routes, floor care, chemicals and reliability

Custodian screening questions work best when they sound like the job. Ask the candidate to walk you through their last route, from clock-in to lock-up: how many rooms or how much floor, in what order, with which equipment, and what they did when the shift ran short. A custodian who has carried a route answers with a sequence, a number and a shortcut they learned. Then check chemical safety, floor care equipment and reliability, because a building that is cleaned well three nights and missed the fourth still gets the complaint.

This page covers custodians, janitors and building cleaners in schools, offices, healthcare, manufacturing and residential buildings. If the role is mostly repairs, use maintenance technician screening questions. For high-volume hiring days across several entry-level roles, the light industrial screening questions show how to run a seven-minute screen.

Match the building before you match the candidate

Safety rules that shape the screen

Under OSHA's Hazard Communication standard, employers must train workers on the hazardous chemicals in their work area and keep safety data sheets available. Custodians who may contact blood or other potentially infectious materials, for example cleaning spills or handling regulated waste in patient areas, are covered by the bloodborne pathogens standard, which requires training and requires the employer to offer hepatitis B vaccination at no cost. Those are the employer's duties, not the candidate's, but a candidate who has worked under them describes the habits that come with them.

Age matters for one common duty. The Department of Labor's child labor fact sheet explains that Hazardous Occupations Order 12 bars workers under 18 from operating balers and compactors, with narrow exceptions for loading certain paper balers. If the route includes a compactor or cardboard baler, "Are you at least 18?" is a lawful, job-related question. Do not ask for a date of birth.

Knockout questions

Route and routine questions

5. "Walk me through your last route, from clock-in to clock-out."
   • Strong answer: a sequence with numbers: "Two floors, about 30 offices, six restrooms. Trash first, then restrooms, then vacuum, then the lobby last so it looks right in the morning."
   • Red flag: "I cleaned everything." No order, no numbers.
6. "How do you clean a restroom, start to finish?"
   • Strong answer: top to bottom and clean to dirty, restocks, uses separate cloths or color codes for toilets and sinks, lets disinfectant sit for its contact time, mops last toward the door, puts out a wet floor sign.
   • Red flag: same cloth for everything, sprays and wipes immediately.
7. "You are behind and there's an hour left. What gets done and what waits?"
   • Strong answer: restrooms, trash and anything health-related first, tells the supervisor what was skipped.
   • Red flag: skips things quietly and hopes nobody notices.

Floor care and equipment

8. "Which floor machines have you run? Describe stripping and refinishing a floor."
   • Strong answer: names the machines (auto scrubber, swing buffer, burnisher, extractor), then describes the steps: sweep, strip, rinse, neutralize, let dry, several thin coats of finish with drying time between.
   • Red flag: has watched it done, or describes one thick coat.
9. "What do you check on a machine before you use it?"
   • Strong answer: cord and plug or battery charge, pads, squeegee, tanks, and reports damaged equipment.
   • Red flag: uses a machine with a frayed cord "because it still works".

Chemical and biohazard safety

10. "What chemicals should never be mixed, and how do you know what's in a bottle?"
    • Strong answer: never mix bleach with ammonia or acids, never mix products at all unless the label says to, reads labels and the safety data sheet, uses the dispensing system, labels every secondary bottle.
    • Red flag: mixes products to "make it stronger", or uses unlabeled spray bottles.
11. "How do you clean up a blood or vomit spill?"
    • Strong answer: gloves and other PPE, spill kit or absorbent, disinfectant with the right contact time, disposes of materials per the site's rules, washes hands, reports it.
    • Red flag: mops it with the general floor mop.
12. "What do you do when a floor is wet and people are still walking through?"
    • Strong answer: signs out before starting, cleans half a corridor at a time, dries the floor, removes signs when dry.
    • Red flag: signs are optional.

Trust and reliability

13. "You find a wallet or cash on a desk while cleaning. What do you do?"
    • Strong answer: leaves it or turns it in per the site's policy, tells the supervisor.
    • Red flag: hesitates, or would "hold onto it" until someone asks.
14. "Tell me about your attendance at your last job. How many shifts did you miss in your last three months, and how did you let them know?"
    • Strong answer: an honest number and a proper call-off before the shift.
    • Red flag: no-call no-shows, or vague about the number. Do not ask why they missed; ask about notice.
15. "How do you lock up and set the alarm at the end of a night route?"
    • Strong answer: a routine: checks doors and windows, lights, logs the time, knows who to call if the alarm will not arm.
    • Red flag: props doors open to take out trash and leaves them.

A 10-minute phone-screen flow

1. Minutes 0 to 2: the building, the shift, the route size and the pay.
2. Minutes 2 to 4: knockouts 1 to 4.
3. Minutes 4 to 7: route question 5, restroom question 6, and floor care 8 if the building has hard floors.
4. Minutes 7 to 9: chemical question 10, and 11 for healthcare or schools; trust question 13.
5. Minutes 9 to 10: attendance question 14, their questions, and the next step.

How custodial experience gets overstated

• Home cleaning as commercial cleaning. Useful habits, but not a 40,000-square-foot night route with a ride-on scrubber.
• Floor care by proximity. "Did floors" means ran the burnisher once a week, while a floor crew stripped and refinished. Ask who did the stripping.
• Day porter as night custodian. Restocking and spot cleaning in a busy lobby is a different job from a full route alone at night.
• Healthcare cleaning without the protocols. Cleaned offices in a hospital building but never a patient room, isolation room or terminal clean.
• Lead title without lead duties. Ask how many people they scheduled, trained or checked, and who signed their timesheets.

Scoring the screen

A candidate who scores 0 on chemical safety should not go to a hospital or school site, however strong the rest of the screen. Tell the client why in one line, so the decision is based on what the candidate said.

Legal cautions

Describe physical duties, such as lifting trash bags up to a stated weight or standing for the full shift, and ask whether they can do them with or without accommodation. Do not ask about injuries, health, age beyond the 18-or-older question where compactors are involved, family, religion, or national origin. If a school or client runs a criminal background check, follow the notice and consent process and any local fair chance rules; see ban-the-box interview questions. The full list of questions to avoid and what to ask instead is in illegal interview questions.