Occupational safety and health laws
These laws protect people who work on site. Typical duties:
- Give training, helmets, gloves, harnesses and other protective gear.
- Guard heights, openings and moving machines (railings, covers).
- Keep tools and ladders in safe condition; switch off and lock power before repairs.
- Report accidents and keep records; give rest and clean drinking water.
Examples in different countries: an industrial safety and health act in Japan, and the Building and Other Construction Workers law in India.
Building laws
Building laws (building codes) make sure a building is strong, healthy and safe in a fire. They give rules on structure, height and area, fire exits and escape routes, fire resistance of materials, light and ventilation and lifts and stairs. Services must follow them, for example a duct passing a fire wall must have a fire damper. Examples: the Building Standards Act in Japan and the National Building Code in India.
Laws on building services
Special rules cover each service:
- Electricity: only qualified or licensed people may do wiring; installations are inspected and earthed.
- Water and drainage: clean supply and proper sewage connection; approved fittings and materials.
- Gas and boilers: licensed installers, safe flues, regular inspection.
- Fire protection: alarms, sprinklers and extinguishers fitted and checked regularly.
- Lifts: periodic inspection and safe design.
Environmental laws
These laws limit harm to air, water and land. For services they cover: refrigerants (old gases harmed the ozone layer; the Montreal Protocol phases them out, and many countries require leaks to be fixed and gas to be recovered), energy saving (building energy codes set limits for lighting and air conditioning), waste water (treat before release), noise and dust from sites. Leaks are measured as CO2 equivalent = mass x GWP.
Key formulas and definitions
- CO2 equivalent = mass of gas x GWP
- Energy = power (kW) x time (h)
- Number needed = area / rule area (round up)
- One job can fall under more than one law
Worked examples
1. Rule: 1 extinguisher per 200 m2 (round up). How many for 900 m2?
900 / 200 = 4.5, so 5 extinguishers.
2. Rule: exits 2 m wide per 100 people (or part of 100). Width for 350 people?
350 people = 4 groups of 100 (rounded up). 4 x 2 = 8 m.
3. 12 kg of a gas with GWP 2000 leaks. Find the CO2 equivalent.
12 x 2000 = 24,000 kg = 24 tonnes of CO2e.
4. An AC uses 1.5 kW for 8 h/day for 30 days. Raising the set temperature by 3 degrees saves about 18%. How much is saved?
Energy = 1.5 x 8 x 30 = 360 kWh. Saved = 0.18 x 360 = 64.8 kWh.
Common mistakes
- Thinking only one law applies to a job.
- Letting an unqualified person do electrical or gas work.
- Hiding faulty work behind walls before inspection.
- Releasing old refrigerant into the air instead of recovering it.