Acid + Caustic Chemical Handling Reference

Why this matters

Service techs handle aggressive chemicals constantly - drain cleaners, descalers, pool chlorine + acid, boiler treatment, masonry cleaners, caustic degreasers. One careless splash to the eye OR forearm = serious injury. The tech who handles chemicals like a chemist (not like a homeowner) avoids the burn that ends a career. This is the field card.

The two families

Acids (pH below 7): muriatic, sulfuric, hydrochloric, phosphoric, oxalic. Used for descaling, masonry cleaning, pool pH down, drain cleaners.

Bases / caustics (pH above 7): sodium hydroxide (lye), potassium hydroxide, sodium hypochlorite (bleach), ammonia. Used for drain cleaners (caustic side), oven cleaner, masonry strippers.

Both burn skin + eyes + respiratory tract. Acids burn fast + visibly; caustics burn slower + deeper (penetrate tissue before pain registers). Caustics are arguably more dangerous because the damage is done before you react.

Never mix

The most-important rule in chemical work:

• Acid + bleach → chlorine gas (deadly)
• Bleach + ammonia → chloramine gas (deadly)
• Acid + caustic drain cleaner → violent reaction (bubbling, splashing, heat)
• Concentrated acid + water (wrong order) → splatter (always pour acid INTO water, never water into acid)

If you don't know what's already in a drain OR tank, assume it could react. Flush first; introduce new chemical only when you can verify what's there.

PPE non-negotiable

For any acid OR caustic work:

• Chemical splash goggles (not just safety glasses; full seal against splash)
• Face shield for pouring + mixing
• Nitrile OR neoprene gloves (chemical-rated; not just latex)
• Chemical apron for prolonged work
• Closed-toe boots + long pants
• Respirator with appropriate cartridge (acid gas, organic vapor, OR combination) for vapors

Skip any of these to save time - single splash justifies all of them.

Storage

• Acids + bases stored SEPARATELY (different shelves OR cabinets)
• Original labeled containers (never decant into food containers)
• Cool, dry, ventilated location
• Off the truck floor (where they can fall + break)
• Locked when truck unattended (children + curious people)
• Manufacturer SDS (Safety Data Sheet) accessible

Reading the SDS

OSHA-required document for any commercial chemical. Sections that matter:

• Section 2: Hazards (skin, eye, respiratory, ingestion)
• Section 4: First aid (eye flush, skin contact, inhalation, ingestion)
• Section 5: Firefighting (extinguisher type)
• Section 6: Spill response
• Section 7: Handling + storage
• Section 8: PPE
• Section 10: Reactivity (what NOT to mix)

Keep SDS for every chemical on the truck. Customer's right to know if asked.

Common service chemicals + their hazards

Muriatic acid (hydrochloric, 31%):

• Pool pH down, concrete cleaning, masonry
• Fumes are corrosive to lungs + everything metal nearby
• Always dilute by adding acid to water (never reverse)
• Storage: vented area; fumes corrode tools

Sulfuric acid drain cleaner:

• Highly aggressive on organic matter (hair, grease, paper)
• Generates heat on contact with water - can boil
• Damages PVC + ABS pipe at full strength
• Often the cause of pipe failure 6 months after "drain cleaning service"

Sodium hydroxide (lye) drain cleaner:

• Saponifies grease (turns it into soap)
• Generates heat on contact with water
• Caustic burn deep + slow
• Reacts with aluminum (DON'T use in aluminum sinks OR with aluminum fittings)

Sodium hypochlorite (bleach):

• Pool sanitizer, disinfectant, mold/mildew treatment
• Releases chlorine gas if acid added
• Bleaches fabric on contact (customer property concern)
• Decomposes over time (old bleach less effective)

Pool chemicals:

• Calcium hypochlorite (shock): solid, oxidizer, reacts violently with organic contamination
• Trichlor / dichlor (tabs): chlorinated isocyanurates
• Muriatic acid (pH down): as above
• Sodium bicarbonate + sodium carbonate (alkalinity adjusters): safer
• NEVER mix shock with trichlor / dichlor in close proximity

Phosphoric acid:

• Descaling + rust removal
• Less aggressive than HCl / H2SO4 but still acid
• Common in HVAC coil cleaners

Hydrofluoric acid (HF):

• Etches glass; some specialty cleaners
• EXTREMELY DANGEROUS - penetrates skin painlessly + attacks bone
• Calcium gluconate gel must be on hand if working with HF
• If exposed: call medical immediately; don't wait for symptoms

Acid spill response

1. Don't panic; the chemical is on the floor, not on you yet
2. Get bystanders away from the area
3. Ventilate (open windows, doors)
4. Apply neutralizer:

• For acid: sodium bicarbonate (baking soda), sodium carbonate (washing soda)
• For base: weak vinegar OR citric acid solution

1. Absorb with cat litter OR commercial absorbent
2. Sweep into a bag; dispose per hazmat rules
3. Wash the area thoroughly

For large spills (gallons+): evacuate + call hazmat. Don't try to handle alone.

Skin contact response

1. Flush IMMEDIATELY with copious water (15 minutes minimum for acid OR strong base)
2. Don't try to neutralize on skin (acid + base reaction generates heat)
3. Remove contaminated clothing while flushing
4. Continue flushing 15+ minutes
5. Seek medical attention even for "small" exposures (some chemicals damage subsurface)

For HF specifically: flush + apply calcium gluconate gel + go to ER immediately.

Eye contact response

1. Flush eye(s) immediately at eye-wash station OR with clean running water
2. Hold eyelids open; flush from inside corner outward
3. Continue 15 minutes minimum
4. Go to ER (call ahead)
5. Bring SDS to ER if possible

A 30-second pause to find the eye wash = significant additional damage. Get to water immediately, then think.

Inhalation response

Smelled fumes + feeling lightheaded?

1. Get outside / to fresh air immediately
2. Don't drive
3. Call for medical evaluation (chlorine + chloramine exposure may have delayed symptoms)
4. Monitor for breathing difficulty next 24 hours

Drain cleaner customer education

Customers commonly:

• Pour Drano + commercial cleaners; doesn't work; call you
• Don't tell you what they poured
• ASK YOU to use stronger chemical

The right approach:

• Ask "what's been poured in this drain already?"
• Flush with cold water before introducing your chemical (dilutes residue)
• Use mechanical method (auger / snake) BEFORE chemical when possible
• If chemical needed: phosphoric / mild acid first; sulfuric only as last resort
• Document what you used (in service notes + customer notification)

When to refuse the job

Some situations: walk away.

References

• OSHA 1910.1200 (Hazard Communication / SDS requirement)
• OSHA 1910.132 (PPE)
• ANSI Z358.1 (emergency eyewash + shower)
• Manufacturer SDS for every chemical on truck
• Manuall internal: Common Cleaning Chemicals, Asbestos + Lead Safety