Why this guide exists
Duct cleaning in India is unregulated: anyone with a vacuum and a visiting card can bid. The gap between vendors shows up only after award — in what they can’t document. This checklist moves that discovery to before the purchase order. It is deliberately vendor-neutral; run it on us too.
The five-artifact checklist
1. Certification — with a number you can check
Ask: “Who is the certified specialist managing this project, and what is their certificate number?” Verify: NADCA’s Find-a-Professional directory (nadca.com) lists member companies and certified ASCS holders publicly. Check the company and the individual separately, and note the expiry date. “NADCA-trained”, “NADCA-based methods” or an unverifiable logo on a brochure are not certification.
2. ISO certificates — with the certifying body named
Ask for the certificate scan, not a logo. Read three fields: the certificate number, the certifying body, and the validity date. Check that the body is what it claims to be — accreditation claims (“UKAS”, “IAF”) should match the actual registry, and an expired or withdrawn certificate on a live brochure is a disqualifying integrity signal, not a paperwork slip.
3. Liability insurance — policy number and limit
HVAC cleaning puts technicians and equipment above your ceilings and inside your plant rooms. Ask for the public liability policy number, insurer and aggregate limit, and confirm validity. A vendor who has never been asked this question has never worked for a client who audits.
4. A sample project report
The single most revealing artifact. Ask: “Show me the closure report from a comparable project.” A real one contains: pre-clean inspection photos, a containment plan, dated cleaning logs, matched before/after photos of the same duct sections, and a completion certificate. If the “report” is a one-page letter of thanks, the work will look the same.
5. Statutory basics
GST registration matching the invoicing entity, and registered business details consistent across the quotation, website and directory listings. Inconsistent names and addresses across documents predict inconsistent everything else.
Scoring what comes back
- All five, unprompted or within a day: shortlist.
- Certification missing but the rest solid: you are buying general cleaning, not specialist air hygiene — price it accordingly.
- Nothing verifiable: the quotation is the only real document, and the low number on it is explained.
Our own answers to all five are public on the credentials page, and step one of any engagement — the inspection — produces the photo-documented report this checklist asks for, before you commit to anything.