Labour from base salaries; health care with check-ups for all staff

User, October 2026: option to enter base salaries; the company should
provide proper extra health care with check-ups for all staff.

- worker-safety.md: new "Health care for all staff" policy (decided
  October 2026): group health insurance (inpatient and outpatient) and a
  yearly check-up for everyone, office included, on top of social
  security; the occupational checks Thai law requires for risk-factor
  work (Ministerial Regulation B.E. 2547: within 30 days, then yearly, by
  an occupational physician, records kept 2 years after the job ends) for
  the press floor, galvanics and maintenance; planning costs with sources
  checked October 2026 (group insurance ~8,000 to 18,006 THB a head a
  year, plan ~15,000; Rajavej Chiang Mai check-ups 1,290 to 5,990 THB,
  plan ~2,500 plus ~1,500 risk-factor tests, estimates); social security
  5 % up to the 17,500 THB ceiling since 1 January 2026.
- revenue-model.md: cutting engineer 50,000 THB is base salary; health
  care on top of the x1.3 (~0.35M THB a year at the start fleet); what the
  x1.3 is made of.
- Fleet calculator: base salaries per role (the revenue model loaded
  rates / 1.3; cutting engineer 50,000), employer social security 5 %
  capped at 17,500, 25 % overtime, bonus and PPE, health insurance and
  check-ups for all staff incl. 4 office staff (scale.md 3 to 5), risk-
  factor tests for the press floor, galvanics and maintenance; all as
  editable assumptions; people table gains office and all-staff rows.
  Defaults: labour 5.25M THB (was 4.67M loaded), direct cost 1.90 USD a
  record, EBITDA 2.19M USD.

docs/worker-safety.md

@@ -25,6 +25,41 @@ commitments:
   in [crane, workshop and tours](crane-workshop-tours.md).
 - **Visitors** never share the floor's hazards: tours run in a glazed
   corridor with its own air and no PPE requirement.
+- **Health care for all staff (decided October 2026).** On top of the
+  statutory social security, the company provides every member of staff,
+  office included, with group health insurance (inpatient and outpatient)
+  and a yearly health check-up. Staff in risk-factor work also get the
+  occupational checks Thai law requires, which the general check-up does
+  not replace:
+  - **The legal minimum.** The Ministerial Regulation on health check-ups
+    of employees (B.E. 2547, 2004) covers work with hazardous chemicals,
+    heat, noise and similar risk factors: a check within 30 days of
+    starting such work, then at least once a year, by a physician trained
+    in occupational medicine, physical and mental, with the records kept
+    until two years after the job ends
+    ([summary](https://www.thailandlawoffice.com/legal-articles/266),
+    [text](https://natlex.ilo.org/dyn/natlex2/natlex2/files/download/96400/THA96400%20Eng.pdf)).
+    Here that is the press floor (steam heat, noise), galvanics (nickel
+    salts, silver nitrate, acids) and maintenance; hearing, lung function
+    and metal tests are the likely panel, for the occupational physician
+    to set.
+  - **Planning costs** (checked October 2026, no quote yet): group health
+    insurance about 8,000 to 12,000 THB a head a year for local plans
+    ([Thailand Starter Kit](https://thailandstarterkit.com/business/group-health-insurance)),
+    AXA's SME plans 9,394, 14,925 and 18,006 THB at 25 staff
+    ([CheckDi](https://checkdi.com/th/business-insurance/group-health?lg=th));
+    the plan uses ~15,000. Check-ups at Rajavej Chiang Mai cost 1,290 THB
+    (age 18 to 30), 1,790 (31 to 40) and 3,290 to 5,990 (over 40) in 2026
+    ([programmes](https://rajavejchiangmai.com/en/pagekage/health-checkup-program-2026));
+    the plan uses ~2,500 a head plus ~1,500 for the risk-factor tests
+    (estimates).
+  - **Social security**, for reference: the employer pays 5 % of salary
+    up to a ceiling raised from 15,000 to 17,500 THB a month on 1 January
+    2026, so at most 875 THB a month a head
+    ([Sprout](https://sprout.co.th/en/blogs/thailand-social-security-contribution-2026-section-33)).
+
+  The [press fleet calculator](fleet-calculator.html) costs all of this per
+  head with the fleet's staffing.
 
 Safety infrastructure (training program, clean-room specification,
 decontamination workflow) will be planned alongside the equipment, not after