Army MOS Career Guide

91J — Quartermaster and Chemical Equipment Repairer:
Civilian Career Guide

Army 91J experience spans pumps, water-purification equipment, heaters, decontamination systems, protective filtration, smoke generators, laundry systems, small engines, electrical circuits, fuel delivery, cooling, diagnostics, and field repair. Civilian paths lead to industrial maintenance, pump service, water operations, HVACR, and maintenance supervision. State licenses, EPA refrigerant certification, and employer qualification remain separate requirements.

Army MOS · Chapter 10C page 310 verified

BLS May 2025 industrial maintenance, water, HVACR, field-service, and supervision wages

State operator licenses, EPA certification, and employer sign-off require separate verification

Army Chapter 10C note

Chapter 10C identifies 91J as Quartermaster and Chemical Equipment Repairer, an ACASP-designated MOS effective October 2025. The entry covers field maintenance on electrical and fuel heaters, pumps, tactical and lightweight reverse-osmosis water purification, decontamination, protective filtration, smoke generation, laundry equipment, and internal-combustion ignition, fuel, cooling, and electrical systems. It also includes battlefield damage assessment and repair, junior-Soldier supervision, and technical guidance.

Start Here

Choose the part you need first.

Industrial Machinery Mechanic$46k – $95kBroadest direct path

Pump and Field Equipment Technician$36k – $77kStrong mobile-service path

Water and Wastewater Treatment Operator$39k – $91kRegulated utility path

HVACR Technician$40k – $95kBest after refrigerant training

Maintenance Supervisor$50k – $127kBest for experienced leaders

See full role breakdowns: demand data, hiring notes, and employer expectations →

Translate the Equipment Families

Show employers which pumps, treatment systems, heaters, engines, and controls you diagnosed.

Separate mechanical, electrical, water, environmental, and supervisory evidence before choosing a civilian maintenance lane.

Build My 91J Blueprint →

Section 01

Top Civilian Role Matches for 91J

Industrial Machinery Mechanic Broadest direct path

$46k – $95k

Pumps, heaters, laundry machinery, engines, electrical components, fuel systems, cooling systems, and preventive maintenance create the broadest 91J civilian bridge. Manufacturers, food processors, laundries, utilities, facilities, and service contractors hire industrial machinery mechanics. Military field repair does not prove experience on every production line or control architecture. Quantify equipment families, inspections, work orders, test instruments, mechanical and electrical faults, parts replaced, repeat failures, restoration time, preventive schedules, and equipment availability.

Industrial equipmentPumpsEnginesDiagnostics

Broadest direct path

Source: BLS OEWS May 2025 national wage tables · Median $64,520; 10th to 90th percentile $46,120 to $95,170

Pump and Field Equipment Technician

$36k – $77k

Liquid pumps, pumping systems, portable equipment, power sources, hoses, controls, engines, and field troubleshooting map to pump and field-equipment service. Rental companies, utilities, environmental firms, manufacturers, construction support companies, and industrial service providers hire technicians. Job titles vary, so this card uses the broader BLS installation and repair benchmark. Show pump types, flow or pressure checks, prime and seal issues, engines, electrical tests, service calls, downtime, repairs, and customer handoff.

PumpsField servicePowerRepair

Strong mobile-service path

Source: BLS OEWS May 2025 national wage tables · Median $49,230; 10th to 90th percentile $36,080 to $77,040

Water and Wastewater Treatment Operator

$39k – $91k

Reverse-osmosis water purification, pumping, filtration, testing, preventive maintenance, and operational checks can support entry into water-treatment operations. Municipal systems, utilities, industrial plants, contractors, and environmental services hire operators. Military water-system qualification does not issue a state operator license, and treatment chemistry or plant scale may differ. Quantify gallons treated, operating hours, tests, parameters monitored, filters, pumps, alarms, maintenance actions, water-quality results, documentation, and any state-approved coursework.

Water treatmentReverse osmosisMonitoringCompliance

Regulated utility path

Source: BLS OEWS May 2025 national wage tables · Median $60,020; 10th to 90th percentile $39,110 to $91,060

HVACR Technician

$40k – $95k

Forced-air heaters, environmental controls, fuel delivery, electrical circuits, airflow, filtration, and troubleshooting provide a partial bridge to HVACR service. Facilities, contractors, manufacturers, government sites, and equipment-service firms hire technicians. Heating-equipment experience does not automatically cover refrigeration circuits, building codes, apprenticeships, or refrigerant handling. Quantify heaters, inspections, voltage checks, combustion or fuel faults, airflow issues, controls, repairs, safety checks, restoration time, and EPA Section 608 status where required.

HeatingElectricalAirflowControls

Best after refrigerant training

Source: BLS OEWS May 2025 national wage tables · Median $61,010; 10th to 90th percentile $40,050 to $95,210

Maintenance Supervisor

$50k – $127k

Experienced 91Js assign work, provide technical guidance, inspect repairs, manage tools and parts, enforce safety, and coordinate equipment readiness across multiple system types. Facilities, utilities, industrial plants, service companies, and contractors hire maintenance supervisors. Employers will evaluate civilian regulatory exposure and team scale separately. Show technicians, shifts, equipment, work orders, backlog, schedule compliance, inspections, first-time fix rate, parts availability, training, incidents, downtime reduction, and operating availability.

SupervisionWork controlSafetyReadiness

Best for experienced leaders

Source: BLS OEWS May 2025 national wage tables · Median $79,860; 10th to 90th percentile $49,600 to $126,790

Section 02

Transferable Strengths: What Civilian Maintenance Employers See

Multi-System Diagnostics

91Js move among pumps, heaters, engines, electrical circuits, filtration, and treatment equipment. Employers read this as adaptable troubleshooting. Quantify system types, tests, fault categories, repairs, and restoration time.

Pump and Fluid-System Maintenance

The MOS maintains liquid pumps and purification systems with mechanical, electrical, and flow dependencies. Employers read this as fluid-system support. Show pumps, operating hours, leaks, seals, pressure checks, and availability.

Portable Utility Operations

Water, heat, decontamination, filtration, and laundry systems deliver essential field services. Employers read this as utility reliability. Quantify output, users supported, setup time, operating hours, interruptions, and quality checks.

Field Repair Under Constraints

Battlefield damage assessment and repair requires prioritizing safe temporary restoration with limited resources. Employers read this as field-service judgment. Distinguish temporary repair from permanent technical authority and document results.

Cross-Trade Technical Guidance

Experienced 91Js supervise junior personnel across varied equipment families. Employers read this as maintenance leadership. Quantify technicians, assignments, inspections, training, repeat-fault reduction, safety, and equipment availability.

Section 03

Common Mistakes 91J Veterans Make

Listing every machine without choosing a lane

A long equipment list makes 91J experience look scattered. Group the record into pumps and fluid systems, water treatment, heaters and environmental controls, engines, or maintenance leadership, then lead with the family that matches the job.

Claiming licenses from military qualification

Military water purification, heater, or environmental-equipment work does not automatically issue a state water-operator license, HVAC trade license, EPA Section 608 credential, or employer authorization. Name current civilian credentials and eligibility separately.

Using BDAR as ordinary repair authority

Battlefield damage assessment and repair is valuable evidence of fault isolation and constrained recovery, but temporary battlefield criteria may not satisfy civilian codes, warranties, or manufacturer procedures. Translate the judgment while stating the final authority accurately.

Section 04

Credentials That Improve Civilian Marketability

SMRP Certified Maintenance and Reliability Technician (CMRT)

Cost $250 member; $300 nonmember; $195 veteran examTime Application and competency-based exam; experience strongly recommendedFormat Professional maintenance certification

SMRP Certified Maintenance and Reliability Technician (CMRT) can validate maintenance practices across preventive work, troubleshooting, corrective repair, and reliability. It fits 91Js targeting industrial or facility maintenance and is less useful when a state license is the actual hiring gate.

Maintenance signal · Best for industrial equipment roles

EPA Section 608 Technician Certification

Cost Approved-provider testing fees varyTime Pass an EPA-approved Core and applicable Type examFormat Federal technician certification that does not expire

EPA Section 608 Technician Certification is required for technicians who service equipment in ways that could release regulated refrigerants. Heater experience alone does not satisfy the requirement, and candidates should select the certification type that matches the civilian equipment they will service.

Regulatory gateway · Required for covered refrigerant work

State Water Treatment Operator Certification

Cost Application, exam, training, and renewal fees vary by stateTime State-specific education, experience, exam, and renewal requirementsFormat State operator license or certification

State Water Treatment Operator Certification can open municipal and industrial water roles when 91J purification experience aligns with state requirements. EPA explains that implementation occurs through state programs, so candidates must check the state where they intend to work before paying for training.

State gateway · Best for water-operations paths

Section 05

Resume Translation: From Field Equipment Repair to Industrial Maintenance

Organize the MOS by equipment family, diagnostic method, repair authority, and measurable utility or availability outcome.

Before: Military-centered language

Maintained quartermaster and chemical equipment, performed BDAR, and supervised junior Soldiers.

After: Civilian employer language

Maintenance technician with [years] supporting [number] pumps, water-purification units, forced-air heaters, filtration systems, laundry systems, and engine-driven equipment across [number] sites. Completed [number] inspections and work orders, using [meters, gauges, or test equipment] to isolate [number] electrical, fuel, cooling, flow, pressure, engine, or control faults. Repaired or replaced authorized components, restored service within [time], and sustained [availability rate] for systems delivering [gallons, heat output, operating hours, or users supported]. Maintained [number] records, reduced repeat failures by [percent], and trained [number] technicians to [qualification result]. State operator licenses, EPA certification, trade licenses, and employer sign-off are listed separately from Army qualifications.

The 91J Translation Formula

Military term	Civilian translation	Proof to show
Tactical RO system	portable reverse-osmosis water-treatment equipment	gallons, hours, tests, filters, quality results
Forced-air heater	fuel-fired portable heating and airflow system	units, inspections, faults, restoration
Decontamination system	special-purpose pumping, heating, and fluid-delivery equipment	systems, setup time, checks, uptime
Protective filter system	powered filtration and environmental-control equipment	filters, airflow checks, alarms, maintenance
BDAR	constrained damage assessment and temporary service restoration	incidents, decisions, time, safe turnover

Always quantify equipment, pumps, gallons, operating hours, work orders, inspections, tests, faults, parts, restoration time, repeat failures, trainees, and availability

Sources reviewed on 2026-07-21: BLS OEWS May 2025, SMRP CMRT, EPA Section 608 requirements, EPA operator certification overview. Salary bands use May 2025 BLS national 10th to 90th percentile estimates rounded for planning. Local pay, state water licensing, EPA certification, trade licensing, manufacturer authorization, and employer requirements vary.

Section 06

91J Civilian Career FAQs

What civilian jobs fit Army MOS 91J?

Strong paths include industrial machinery mechanic, pump or field-equipment technician, water-treatment operator, HVACR technician, and maintenance supervisor. The best path depends on which equipment families, tests, work volume, licenses, and leadership responsibilities appear in the record.

Does 91J experience qualify someone as a water operator?

Not automatically. Water-operator certification is implemented through state programs with different education, experience, examination, and renewal rules. Military purification experience can be relevant evidence, but the state determines whether it satisfies any portion of its requirements.

Does heater maintenance replace EPA Section 608 certification?

No. Section 608 applies when technicians service equipment in ways that could release regulated refrigerants. Forced-air heater work may support electrical, airflow, fuel, and controls experience, but candidates must pass an EPA-approved test for covered refrigerant work.

What should a 91J quantify?

Quantify pumps, heaters, purification units, filtration systems, engines, operating hours, gallons treated, inspections, work orders, instruments, faults, parts, restoration time, repeat failures, utility output, people trained, safety results, and availability. Identify civilian licenses separately.

Build the Technical Record

Turn varied field equipment into a focused civilian maintenance plan.

CommandPath can organize your equipment families, tests, faults, repairs, work orders, safety record, leadership, and license gaps.